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2011

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Articles 1 - 30 of 7307

Full-Text Articles in Life Sciences

Economic And Social Impacts Of Wildfires And Invasive Plants In American Deserts: Lessons From The Great Basin, Mark Brunson, John Tanaka Oct 2014

Economic And Social Impacts Of Wildfires And Invasive Plants In American Deserts: Lessons From The Great Basin, Mark Brunson, John Tanaka

John A Tanaka

Research on the impacts of wildfire and invasive plants in rangelands has focused on biophysical rather than human dimensions of these environmental processes. We offer a synthetic perspective on economic and social aspects of wildfire and invasive plants in American deserts, focusing on the Great Basin because greater research attention has been given to the effects of cheatgrass expansion than to other desert wildfire/invasion cycles. We focus first on impacts at the level of the individual decision-maker, then on impacts experienced at the human community or larger socio-political scales. Economic impacts of wildfire differ from those of invasive grasses ...


Chapter 9. A Social And Economic Assessment Of Rangeland Conservation Practices, John Tanaka, Mark Brunson, L. Allen Torell Oct 2014

Chapter 9. A Social And Economic Assessment Of Rangeland Conservation Practices, John Tanaka, Mark Brunson, L. Allen Torell

John A Tanaka

In this chapter, we examine the literature related to the economic and social aspects of ecosystem services impacted by the conservation practices of the Natural Resources Conservation Service (NRCS) of prescribed grazing, prescribed burning, brush management, upland wildlife habitat, riparian management, and range planting. In addition, we examine the social and economic aspects of invasive species management that cross different conservation practices...


Alterg Anti-Gravity Treadmill Walking Program On An Extremely Obese Female, Jane Shimon, Shawn Simonson, Elaine Long, Brooke Lester Oct 2013

Alterg Anti-Gravity Treadmill Walking Program On An Extremely Obese Female, Jane Shimon, Shawn Simonson, Elaine Long, Brooke Lester

Elaine M. Long

No abstract provided.


Genome-Scale Dynamics Modeling Of The Competition Between Rhodoferax And Geobacter In Anoxic Subsurface Environments, Derek Lovley, Kai Zhuang, Mounir Izallalen, Paula Museor, Hanno Richter, Carla Risso, Radhakrishnan Mahadevan Apr 2012

Genome-Scale Dynamics Modeling Of The Competition Between Rhodoferax And Geobacter In Anoxic Subsurface Environments, Derek Lovley, Kai Zhuang, Mounir Izallalen, Paula Museor, Hanno Richter, Carla Risso, Radhakrishnan Mahadevan

Carla Risso

The advent of rapid complete genome sequencing, and the potential to capture this information in genome-scale metabolic models, provide the possibility of comprehensively modeling microbial community interactions. For example, Rhodoferax and Geobacter species are acetate-oxidizing Fe(III)-reducers that compete in anoxic subsurface environments and this competition may have an influence on the in situ bioremediation of uranium-contaminated groundwater. Therefore, genome-scale models of Geobacter sulfurreducens and Rhodoferax ferrireducens were used to evaluate how Geobacter and Rhodoferax species might compete under diverse conditions found in a uranium-contaminated aquifer in Rifle, CO. The model predicted that at the low rates of acetate ...


First Report Of Hog-Plum (Spondias Pinnata) Leaf Spot Disease, Kunal Mandal Dec 2011

First Report Of Hog-Plum (Spondias Pinnata) Leaf Spot Disease, Kunal Mandal

Kunal Mandal

Hog–plum is a tree species with edible fruits. The plant is naturally distributed in the tropical areas of the Indian subcontinent. Our effort to introduce it in the semi– arid conditions of western India failed as the plants developed severe shot–hole type leaf spot symptoms. Association of a fungus with the disease was detected and its pathogenicity was established. The pathogen was identified to the genus level (Colletotrichum) based on the morphological and molecular markers.


Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending December 31, 2011, Margaret N. Rees Dec 2011

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending December 31, 2011, Margaret N. Rees

Limnological Studies

Project 1

  • Technical assistance with the implementation of the Interagency Monitoring Action Plan (IMAP) for Quagga Mussels is ongoing; remaining analyses are underway with report delivery rescheduled for 05/2012.
  • Data have been delivered for Veliger abundance and settlement at different depths of Lake Mead with report delivery re-scheduled for 05/2012.
  • Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay
  • The Interagency Quagga Mussel Meeting was held on 11/17/2011; the next meeting is scheduled for 02/16/2011.

Project 2

  • Appendix 7, an addition to the Long-term Limnological and Aquatic Resource Monitoring and Research ...


Proceedings Of International Conference On Chemical, Biological And Environmental Engineering, Srikanta Patnaik Mentor Dec 2011

Proceedings Of International Conference On Chemical, Biological And Environmental Engineering, Srikanta Patnaik Mentor

Conference Proceedings - Full Volumes

International Conference on Chemical, Biological and Environmental Engineering (ICBEE 2011) is the premier forum for the presentation of new advances and research results in the fields of Chemical, Biological and Environmental Engineering covering all aspects of theoretical, experimental, and applied branches. The conference will bring together leading researchers, engineers and scientists in the domain of interest from around the world.

Topics of interest for submission include, but are not limited to: Chemical, Environmental, and Process Engineering

•Environmental engineering and sustainable development • Process design and optimization • Product innovation, development and economics • Process intensification • Nanotechnology • New materials & structured products • Intelligent polymers • Green ...


Occurrence Of The Invasion Associated Marker (Iam) In Campylobacter Jejuni Isolated From Cattle, Yasser M. Sanad, Issmat I. Kassem, Zhe Liu, Jun Lin, Jeffrey T. Lejeune, Gireesh Rajashekara Dec 2011

Occurrence Of The Invasion Associated Marker (Iam) In Campylobacter Jejuni Isolated From Cattle, Yasser M. Sanad, Issmat I. Kassem, Zhe Liu, Jun Lin, Jeffrey T. Lejeune, Gireesh Rajashekara

Animal Science Publications and Other Works

Background

The invasion associated marker (iam) has been detected in the majority of invasive Campylobacter jejuni retrieved from humans. Furthermore, the detection of iam in C. jejuni isolated from two important hosts, humans and chickens, suggested a role for this marker in C. jejuni's colonization of multiple hosts. However, no data exist regarding the occurrence of this marker in C. jejuni isolated from non-poultry food-animals such as cattle, an increasingly important source for human infections. Since little is known about the genetics associated with C. jejuni's capability for colonizing physiologically disparate hosts, we investigated the occurrence of the ...


Spt5 Affects The Rate Of Mrna Degradation And Physically Interacts With Ccr4 But Does Not Control Mrna Deadenylation, Yajun Cui, Yueh-Chin Chiang, Palaniswamy Viswanathan, Darren J. Lee, Clyde L. Denis Dec 2011

Spt5 Affects The Rate Of Mrna Degradation And Physically Interacts With Ccr4 But Does Not Control Mrna Deadenylation, Yajun Cui, Yueh-Chin Chiang, Palaniswamy Viswanathan, Darren J. Lee, Clyde L. Denis

New Hampshire Agricultural Experiment Station Publications

The CCR4-NOT complex has been shown to have multiple roles in mRNA metabolism, including that of transcriptional elongation, mRNA transport, and nuclear exosome function, but the primary function of CCR4 and CAF1 is in the deadenylation and degradation of cytoplasmic mRNA. As previous genetic analysis supported an interaction between SPT5, known to be involved in transcriptional elongation, and that of CCR4, the physical association of SPT5 with CCR4 was examined. A two-hybrid screen utilizing the deadenylase domain of CCR4 as a bait identified SPT5 as a potential interacting protein. SPT5 at its physiological concentration was shown to immunoprecipitate CCR4 and ...


A New Variety Of Lomatium Ravenii (Apiaceae) From The Northern Great Basin And Adjacent Owyhee Region, Kimberly M. Carlson, Donald H. Mansfield, James F. Smith Dec 2011

A New Variety Of Lomatium Ravenii (Apiaceae) From The Northern Great Basin And Adjacent Owyhee Region, Kimberly M. Carlson, Donald H. Mansfield, James F. Smith

Aliso: A Journal of Systematic and Floristic Botany

Variability in the group of Lomatium species comprising L. nevadense, L. ravenii, and L. foeniculaceum has led to conflicting classification schemes. While some taxonomists have treated L. ravenii as a distinct species made up of all the populations from California, Nevada, Idaho, and Oregon, others considered L. ravenii to be nothing more than a morphological extreme of L. nevadense. We examined morphological and phylogenetic data from across the range of L. ravenii, concluding that variation in the species warrants varietal distinction. Non-metric multidimensional scaling analysis of 29 populations shows two distinct groups—one from the vicinity of Ravendale, California, and ...


Two Epiparasitic Species Of Phoradendron (Viscaceae) From Honduras: One New And For The Other A Range Extension And Host Determination, Delbert Wiens, Clyde L. Calvin Dec 2011

Two Epiparasitic Species Of Phoradendron (Viscaceae) From Honduras: One New And For The Other A Range Extension And Host Determination, Delbert Wiens, Clyde L. Calvin

Aliso: A Journal of Systematic and Floristic Botany

A new species of Phoradendron, Ph. mathiasenii, is described, and a range extension and host are given for Ph. tikalense. Both species are from Honduras and grow as epiparasites, i.e., mistletoes parasitizing other mistletoes. The parasitic host for both epiparasitic species of Phoradendron is Psittacanthus angustifolius (Loranthaceae), which in turn is parasitic on the terrestrial host, Pinus oocarpa, a common forest tree in the collection area. Although the two species of Phoradendron parasitize the same parasitic host and co-occur in the area, they are distinct morphologically. Many plants of Ph. mathiasenii were observed at several collection sites in the ...


Cover Page Dec 2011

Cover Page

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


The Flora Of Greater San Quintín, Baja California, Mexico (2005–2010), Sula E. Vanderplank Dec 2011

The Flora Of Greater San Quintín, Baja California, Mexico (2005–2010), Sula E. Vanderplank

Aliso: A Journal of Systematic and Floristic Botany

The plants of San Quintín (Baja California, Mexico) were documented through intensive fieldwork and collection of herbarium specimens to create a checklist of species. The region is located near the southernmost extent of the California Floristic Province, and the flora is influenced by the adjacent desert to the south. A total of 435 plant taxa were documented, of which 82% are native plants. Almost one in three native plant taxa in Greater San Quintín is a sensitive species, here documented as rare and/or locally endemic, and many taxa have yet to be evaluated fully for rarity and threats. Four ...


Rediscovery Of Monotropastrum Sciaphilum (Andres) G.D.Wallace In China After 91 Years, Min Shen, Chang-Qin Zhang, Gary D. Wallace Dec 2011

Rediscovery Of Monotropastrum Sciaphilum (Andres) G.D.Wallace In China After 91 Years, Min Shen, Chang-Qin Zhang, Gary D. Wallace

Aliso: A Journal of Systematic and Floristic Botany

Monotropastrum sciaphilum (Ericaceae), a mycoheterotrophic member of subfamily Monotropoideae, was rediscovered at its type locality in Yunnan Province, China, 91 years after it was first collected. The type locality is the only locality from which it is known. Field observations in 2007–2010 indicated that inflorescences emerge from the soil between late April and early September. The restricted distribution of M. sciaphilum recommends its listing in the IUCN red book.


Index Dec 2011

Index

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Enhanced Microbial Utilization Of Recalcitrant Cellulose By An Ex Vivo Cellulosome-Microbe Complex, Chun You, Xiao-Zhou Zhang, Noppadon Sathitsuksanoh, Lee R. Lynd Dec 2011

Enhanced Microbial Utilization Of Recalcitrant Cellulose By An Ex Vivo Cellulosome-Microbe Complex, Chun You, Xiao-Zhou Zhang, Noppadon Sathitsuksanoh, Lee R. Lynd

Dartmouth Scholarship

A cellulosome-microbe complex was assembled ex vivo on the surface of Bacillus subtilis displaying a miniscaffoldin that can bind with three dockerin-containing cellulase components: the endoglucanase Cel5, the processive endoglucanase Cel9, and the cellobiohydrolase Cel48. The hydrolysis performances of the synthetic cellulosome bound to living cells, the synthetic cellulosome, a noncomplexed cellulase mixture with the same catalytic components, and a commercial fungal enzyme mixture were investigated on low-accessibility recalcitrant Avicel and high accessibility regenerated amorphous cellulose (RAC). The cellbound cellulosome exhibited 4.5- and 2.3-fold-higher hydrolysis ability than cell-free cellulosome on Avicel and RAC, respectively. The cellulosome-microbe synergy was ...


Thermal Adaptation And Diversity In Tropical Ecosystems: Evidence From Cicadas (Hemiptera, Cicadidae), Allen F. Sanborn, James E. Heath, Polly K. Phillips, Maxine S. Heath, Fernando G. Noriega Dec 2011

Thermal Adaptation And Diversity In Tropical Ecosystems: Evidence From Cicadas (Hemiptera, Cicadidae), Allen F. Sanborn, James E. Heath, Polly K. Phillips, Maxine S. Heath, Fernando G. Noriega

Department of Biological Sciences

The latitudinal gradient in species diversity is a central problem in ecology. Expeditions covering approximately 16u549 of longitude and 21u49 of latitude and eight Argentine phytogeographic regions provided thermal adaptation data for 64 species of cicadas. We test whether species diversity relates to the diversity of thermal environments within a habitat. There are general patterns of the thermal response values decreasing in cooler floristic provinces and decreasing maximum potential temperature within a habitat except in tropical forest ecosystems. Vertical stratification of the plant communities leads to stratification in species using specific layers of the habitat. There is a decrease in ...


Mechanism And Regulation Of Nucleocytoplasmic Trafficking Of Smad, Xiaochu Chen, Lan Xu Dec 2011

Mechanism And Regulation Of Nucleocytoplasmic Trafficking Of Smad, Xiaochu Chen, Lan Xu

Open Access Publications by UMass Chan Authors

Smad proteins are the intracellular mediators of transforming growth factor beta (TGF-beta) signaling. Smads function as transcription factors and their activities require carboxyl-terminal phosphorylation by TGF-beta receptor kinases which are embedded in the cell membrane. Therefore, the translocation of activated Smads from the cytoplasm into the nucleus is a rate-limiting step in TGF-beta signal transduction into the nucleus. On the other hand, the export of Smads out of the nucleus turns off TGF-beta effect. Such spatial control of Smad ensures a tight regulation of TGF-beta target genes. Several cross-talk pathways have been shown to affect TGF-beta signaling by impairing nuclear ...


Loss Of Activity Mutations In Phospholipase C Zeta Abloishes Calcium Oscillatory Ability Of Human Recombinant Protein In Mouse Ooctyes, J. Kashir, C. Jones, H.C. Lee, K. Rietdork, D. Nikiforaki, C. Durrans, M. Ruas, S.T. Tee, B. Heindryckx, A. Galione, P. Desutter, Rafael Fissore, J. Parrington, K. Coward Dec 2011

Loss Of Activity Mutations In Phospholipase C Zeta Abloishes Calcium Oscillatory Ability Of Human Recombinant Protein In Mouse Ooctyes, J. Kashir, C. Jones, H.C. Lee, K. Rietdork, D. Nikiforaki, C. Durrans, M. Ruas, S.T. Tee, B. Heindryckx, A. Galione, P. Desutter, Rafael Fissore, J. Parrington, K. Coward

Rafael Fissore

BACKGROUND: Mammalian oocyte activation occurs via a series of intracellular calcium (Ca(2+)) oscillations thought to be induced by a sperm-specific phospholipase C zeta (PLCζ). There is now strong evidence to indicate that certain types of human male infertility are caused by failure of the sperm to activate the oocyte in an appropriate manner. Molecular analysis of the PLCζ gene of a male patient with oocyte activation deficiency has previously identified a point mutation causing a histidine to proline substitution at PLCζ residue 398 (PLCζ(H398P)), leading to abnormal Ca(2+) release profiles and reduced oocyte activation efficiency. METHODS AND ...


Transcriptomic Profiles Of Peripheral White Blood Cells In Type Ii Diabetes And Racial Differences In Expression Profiles, Jinghe Mao, Junmei Ai, Xinchun Zhou, Ming Shenwu, Manuel Ong Jr., Marketta Blue, Jasmine T. Washington, Xiaonan Wang, Youping Deng Dec 2011

Transcriptomic Profiles Of Peripheral White Blood Cells In Type Ii Diabetes And Racial Differences In Expression Profiles, Jinghe Mao, Junmei Ai, Xinchun Zhou, Ming Shenwu, Manuel Ong Jr., Marketta Blue, Jasmine T. Washington, Xiaonan Wang, Youping Deng

Faculty Publications

Background: Along with obesity, physical inactivity, and family history of metabolic disorders, African American ethnicity is a risk factor for type 2 diabetes (T2D) in the United States. However, little is known about the differences in gene expression and transcriptomic profiles of blood in T2D between African Americans (AA) and Caucasians (CAU), and microarray analysis of peripheral white blood cells (WBCs) from these two ethnic groups will facilitate our understanding of the underlying molecular mechanism in T2D and identify genetic biomarkers responsible for the disparities.

Results: A whole human genome oligomicroarray of peripheral WBCs was performed on 144 samples obtained ...


A Review Of Baobab (Adansonia Digitata) Products: Effect Of Processing Techniques, Medicinal Properties And Uses, Donatien Kabore, Hagrétou Sawadogo-Lingani, Bréhima Diawara, Clarise Compaoré, Mamoudou H. Dicko Prof., Mogens Jacobsen Dec 2011

A Review Of Baobab (Adansonia Digitata) Products: Effect Of Processing Techniques, Medicinal Properties And Uses, Donatien Kabore, Hagrétou Sawadogo-Lingani, Bréhima Diawara, Clarise Compaoré, Mamoudou H. Dicko Prof., Mogens Jacobsen

Pr. Mamoudou H. DICKO, PhD

A general literature review including the effect of processing techniques, medicinal value and uses of baobab tree is reported in this manuscript. Baobab tree has multi-purpose uses, as it produces food and non-food products such as medicines, fuel, timber, fodder. Every part of the baobab tree is reported to be useful. The seeds, leaves, roots, flowers, fruit pulp and bark of baobab are edible. Baobab leaves are used in the preparation of soup. Seeds are used as a thickening agent in soups, but they can be fermented and used as a flavouring agent or roasted and eaten as snacks. The ...


A Shared Gene Expression Signature In Mouse Models Of Ebv-Associated And Non-Ebv-Associated Burkitt Lymphoma, Kathryn T. Bieging, Kamonwan Fish, Subbarao Bondada, Richard Longnecker Dec 2011

A Shared Gene Expression Signature In Mouse Models Of Ebv-Associated And Non-Ebv-Associated Burkitt Lymphoma, Kathryn T. Bieging, Kamonwan Fish, Subbarao Bondada, Richard Longnecker

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The link between EBV infection and Burkitt lymphoma (BL) is strong, but the mechanism underlying that link has been elusive. We have developed a mouse model for EBV-associated BL in which LMP2A, an EBV latency protein, and MYC are expressed in B cells. Our model has demonstrated the ability of LMP2A to accelerate tumor onset, increase spleen size, and bypass p53 inactivation. Here we describe the results of total gene expression analysis of tumor and pretumor B cells from our transgenic mouse model. Although we see many phenotypic differences and changes in gene expression in pretumor B cells, the transcriptional ...


Pentachlorophenol Decreases Tumor-Cell-Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Tasia Hurd, Jasmine Walker, Margaret M. Whalen Dec 2011

Pentachlorophenol Decreases Tumor-Cell-Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Tasia Hurd, Jasmine Walker, Margaret M. Whalen

Chemistry Faculty Research

Pentachlorophenol (PCP) is an organochlorine pesticide that decreases the tumor-cell killing (lytic) function of human natural killer (NK) cells. NK cells defend against tumor cells and virally infected cells. They bind to these targets, utilizing a variety of cell-surface proteins. This study examined concentrations of PCP that decrease lytic function for alteration of NK binding to tumor targets. Levels of PCP that caused loss of binding function were then examined for effects on expression of cell-surface proteins needed for binding. Exposure to 10 µm PCP for 24 h (which caused a greater than 70% loss of lytic function) decreased NK ...


Morpholino Gene Knockdown In Adult Fundulus Heteroclitus: Role Of Sgk1 In Seawater Acclimation, Emily G. Notch, Joseph R. Shaw, Bonita A. Coutermarsh, Marisa Dzioba, Bruce A. Stanton Dec 2011

Morpholino Gene Knockdown In Adult Fundulus Heteroclitus: Role Of Sgk1 In Seawater Acclimation, Emily G. Notch, Joseph R. Shaw, Bonita A. Coutermarsh, Marisa Dzioba, Bruce A. Stanton

Dartmouth Scholarship

The Atlantic killifish (Fundulus heteroclitus) is an environmental sentinel organism used extensively for studies on environmental toxicants and salt (NaCl) homeostasis. Previous research in our laboratory has shown that rapid acclimation of killifish to seawater is mediated by trafficking of CFTR chloride channels from intracellular vesicles to the plasma membrane in the opercular membrane within the first hour in seawater, which enhances chloride secretion into seawater, thereby contributing to salt homeostasis. Acute transition to seawater is also marked by an increase in both mRNA and protein levels of serum glucocorticoid kinase 1 (SGK1) within 15 minutes of transfer. Although the ...


Identifying Characteristics Of Effective Small Group Learning Valued By Medical Students And Facilitators, Diana T. Robillard, Laura M. Spring, Susan J. Pasquale, Judith A. Savageau Dec 2011

Identifying Characteristics Of Effective Small Group Learning Valued By Medical Students And Facilitators, Diana T. Robillard, Laura M. Spring, Susan J. Pasquale, Judith A. Savageau

Judith A. Savageau

Background: Small group teaching is an important part of undergraduate medical education, providing the ideal setting for learners to clarify misunderstandings, test hypotheses and evaluate ideas. Many schools undergoing curriculum reform have increased the time students spend in small group learning. However, there is an overall paucity of literature examining case-based small group sessions in medical school.

Objective: This study was designed to examine student and facilitator perceptions of effective case-based small group teaching in the pre-clinical years and compare results in order to identify similarities and differences and identify key areas of disconnect so that the small group learning ...


Improving Prenatal Education In A Health Center: A Pilot Study, Marcy Keddy Boucher, Hugh Silk, Judith A. Savageau, Katharine C. Barnard, Mary Flynn Dec 2011

Improving Prenatal Education In A Health Center: A Pilot Study, Marcy Keddy Boucher, Hugh Silk, Judith A. Savageau, Katharine C. Barnard, Mary Flynn

Judith A. Savageau

Background: Currently, the timing and variety of health education topics that are covered during prenatal visits are decided upon by the individual physician caring for the patient. Consequently, some patients do not gain exposure to important subject matter that could potentially improve their satisfaction and pregnancy outcomes. Previously reported studies have found evidence that improved patient education may increase rates of breastfeeding (as well as duration), seat belt use during pregnancy, and decrease preterm low birth weight infants. In addition, one study has shown that when prenatal visits are targeted to specific objectives, the number of prenatal visits can be ...


Development Of Natural Killer Cells Regulated By T-Box Transcription Factors, Scott M. Gordon Dec 2011

Development Of Natural Killer Cells Regulated By T-Box Transcription Factors, Scott M. Gordon

Publicly Accessible Penn Dissertations

Natural killer (NK) cells play critical roles in host defense against tumors and intracellular pathogens. Various transcription factors have been reported to alter NK cell development, but the definitive transcriptional program governing this process is not well understood. Our laboratory has shown previously that the T-box transcription factors T-bet and Eomesodermin (Eomes) direct fate and function in cytotoxic T lymphocytes. We thus endeavored to define the roles of T-bet and Eomes in the differentiation of NK cells. We find that NK progenitor cells give rise to immature-phenotype NK cells, which express the death ligand TRAIL and the transcription factor T-bet ...


The Cytoskeletal Mechanisms Of Cell-Cell Junction Formation In Endothelial Cells, Matthew K. Hoelzle Dec 2011

The Cytoskeletal Mechanisms Of Cell-Cell Junction Formation In Endothelial Cells, Matthew K. Hoelzle

Publicly Accessible Penn Dissertations

Intercellular adhesions are essential for compartmentalization and integrity of tissues in an organism, cell-cell communication, and morphogenesis. The actin cytoskeleton and associated proteins play a vital role in establishing and maintaining cell-cell adhesion. However, the procedure by which cells establish adherens junctions remains largely unclear.

We investigated the dynamics of cell-cell junction formation and the corresponding architecture of the underlying cytoskeleton in cultured human umbilical vein endothelial cells (HUVECs). We show that the initial interaction between cells is mediated by protruding lamellipodia. Upon their retraction, cells maintain contact through thin bridges formed by filopodia-like protrusions connected by VE-cadherin-rich junctions.

Bridges ...


Regional Lysosomal Malfunction Underlies The Selectivity Of Α-Synuclein Neurodegeneration, Kristen A. Malkus Dec 2011

Regional Lysosomal Malfunction Underlies The Selectivity Of Α-Synuclein Neurodegeneration, Kristen A. Malkus

Publicly Accessible Penn Dissertations

Dysfunction of protein homoeostasis has been implicated in the pathogenesis of a diverse array of neurodegenerative disorders. However, each neurodegenerative disease is characterized by the accumulation of particular proteins in select regions of the brain. It remains unclear how dysfunction of a ubiquitous protein degradation pathway results in distinct pathologies. α-Synuclein is a protein whose aggregation and oligomerization has been implicated in several diseases, including Parkinson’s disease (PD). Herein, we investigated regionally selective alterations in α-synuclein degradation to decipher potential mechanisms underlying its role in disease. Chaperone mediated autophagy (CMA), a selective route of direct lysosomal degradation, participates in ...


The Functional Biology Of Il-25, Steven A. Saenz Dec 2011

The Functional Biology Of Il-25, Steven A. Saenz

Publicly Accessible Penn Dissertations

CD4+ T helper (Th) 2 cells secrete interleukin (IL)-4, IL-5 and IL-13 and promote immunity to gastrointestinal helminth infections and chronic inflammation associated with asthma and allergic disorders. However, the innate immune pathways that promote Th2 cell responses remain poorly characterized. The non-hematopoietic cell-derived cytokines thymic stromal lymphopoietin (TSLP), IL-33 and IL-25 (IL-17E) have been implicated in promoting Th2 cell-dependent inflammation at mucosal sites [1-4], but how these cytokines influence innate immune responses are less well defined. Studies in Chapter 2 and 3 examined the cellular mechanisms through which IL-25 promotes Th2 cell responses and demonstrated that IL-25 promotes ...