Digital Commons Network^™

Role Of Electronegativity In Environmentally Persistent Free Radicals (Epfrs) Formation On Zno, Syed Monjur Ahmed, Reuben Oumnov, Orhan Kizilkaya, Randall W. Hall, Philip T. Sprunger, Robert L. Cook

Natural Sciences and Mathematics | Faculty Scholarship

Environmentally persistent free radicals (EPFRs), a group of emerging pollutants, have significantly longer lifetimes than typical free radicals. EPFRs form by the adsorption of organic precursors on a transition metal oxide (TMO) surface involving electron charge transfer between the organic and TMO. In this paper, dihalogenated benzenes were incorporated to study the role of electronegativity in the electron transfer process to obtain a fundamental knowledge of EPFR formation mechanism on ZnO. Upon chemisorption on ZnO nanoparticles at 250 °C, electron paramagnetic resonance (EPR) confirms the formation of oxygen adjacent carbon-centered organic free radicals with concentrations between 1016 and 1017 spins/g. …

New Features Of Laboratory-Generated Epfrs From 1,2-Dichlorobenzene (Dcb) And 2‑Monochlorophenol (Mcp), Lavrent Khachatryan, Marwan Y. Rezk, Divine Nde, Farhana Hasan, Slawomir Lomnicki, Dorin Boldor, Robert Cook, Phillip Sprunger, Randall W. Hall, Stephania Cormier

Natural Sciences and Mathematics | Faculty Scholarship

The present research is primarily focused on investigating the characteristics of environmentally persistent free radicals (EPFRs) generated from commonly recognized aromatic precursors, namely, 1,2-dichlorobenzene (DCB) and 2- monochlorophenol (MCP), within controlled laboratory conditions at a temperature of 230 °C, termed as DCB230 and MCP230 EPFRs, respectively. An intriguing observation has emerged during the creation of EPFRs from MCP and DCB utilizing a catalyst 5% CuO/SiO2, which was prepared through various methods. A previously proposed mechanism, advanced by Dellinger and colleagues (a conventional model), postulated a positive correlation between the degree of hydroxylation on the catalyst’s surface (higher hydroxylated, HH and …

Wildfires Disturb The Natural Skin Microbiota Of Terrestrial Salamanders, Lubna Mulla, Obed Hernandez-Gomez

Natural Sciences and Mathematics | Faculty Scholarship

Environmental change can disturb natural associations between wildlife and microbial symbionts, in many cases to the detriment of host health. We used a North American terrestrial salamander system to assess how the skin microbiota of amphibians responds to wildfires. In northern California's redwood/oak forests, we assessed how recent wildfires affected the skin microbiota of three different salamander species (Taricha sp., Batrachoseps attenuatus, and Ensatina eschscholtzii) over two different sampling seasons in 2018 and 2021. We found species-specific responses to wildfire disturbance on the alpha diversity of the skin microbiota of terrestrial salamanders, although burning in general altered the composition of …

A Comparison Of Candidate Banker Plants For Management Of Pests In Lettuce, Brian N. Hogg, Erik H. Nelson, Kent M. Daane

Natural Sciences and Mathematics | Faculty Scholarship

Agricultural systems are often lacking in resources for natural enemies. Providing alternative prey can help natural enemies persist through periods of low pest abundance, although this approach has been rarely commercially implemented in open field crops. In this study, we tested the potential of eight plant species to provide alternative prey to natural enemies in lettuce fields over a 2-yr period. Results showed that the tested plants would not act as sources of the lettuce aphid Nasonovia ribisnigri Mosley (Hemiptera: Aphididae), the primary lettuce pest. Of the banker plants tested, barley contained high numbers of non-lettuce aphids and appeared to …

Standing Genetic Variation As A Potential Mechanism Of Novel Cave Phenotype Evolution In The Freshwater Isopod, Asellus Aquaticus, Lizet R. Rodas, Serban M. Sarbu, Raluca Bancila, Devon Price, Žiga Fišer, Meredith E. Protas

Natural Sciences and Mathematics | Faculty Scholarship

Novel phenotypes can come about through a variety of mechanisms including standing genetic variation from a founding population. Cave animals are an excellent system in which to study the evolution of novel phenotypes such as loss of pigmentation and eyes. Asellus aquaticus is a freshwater isopod crustacean found in Europe and has both a surface and a cave ecomorph which vary in multiple phenotypic traits. An orange eye phenotype was previously revealed by F2 crosses and backcrosses to the cave parent within two examined Slovenian cave populations. Complete loss of pigmentation, both in eye and body, is epistatic to the …

From The Organismal To Biosphere Levels: Environmental Impacts On The Amphibian Microbiota, Obed Hernandez-Gomez, Jessica Hua

Natural Sciences and Mathematics | Faculty Scholarship

This review summarizes the role of environmental factors on amphibian microbiotas at the organismal, population, community, ecosystem, and biosphere levels. At the organismal-level, tissue source, disease status, and experimental manipulations were the strongest predictors of variation in amphibian microbiotas. At the population-level, habitat quality, disease status, and ancestry were commonly documented as drivers of microbiota turnover. At the community-level, studies focused on how species’ niche influence microbiota structure and function. At the ecosystem-level, abiotic and biotic reservoirs were important contributors to microbiota structure. At the biosphere-level, databases, sample banks, and semi-natural experiments were commonly used to describe microbiota assembly mechanisms …

Wicked Problems And The Invention Of Calculus, Ernesto Diaz

Natural Sciences and Mathematics | Faculty Scholarship

Since the 1980s, wicked problems have represented a category of challenges that defy clear description, cannot be addressed with existing models or theories, and resist experimentation in trying to solve them. This class of problems existed before they were identified and have been unsuccessfully addressed with Thomas Kuhn’s model of scientific discovery, an expectation that requires the identification of a new object and the development of its correct interpretation. This paper proposes an alternative view of scientific discovery using the invention of Calculus as a case study that describes a successful process addressing wicked-like problems from a philosophical perspective, develops …

In Vivo Evaluation Of (-)-Zampanolide Demonstrates Potent And Persistent Antitumor Efficacy When Targeted To The Tumor Site., Leila Takahashi-Ruiz, Joseph D Morris, Phillip Crews, Tyler A Johnson, April L Risinger

Natural Sciences and Mathematics | Faculty Scholarship

Microtubule-stabilizing agents (MSAs) are a class of compounds used in the treatment of triple-negative breast cancer (TNBC), a subtype of breast cancer where chemotherapy remains the standard-of-care for patients. Taxanes like paclitaxel and docetaxel have demonstrated efficacy against TNBC in the clinic, however new classes of MSAs need to be identified due to the rise of taxane resistance in patients. (-)-Zampanolide is a covalent microtubule stabilizer that can circumvent taxane resistance in vitro but has not been evaluated for in vivo antitumor efficacy. Here, we determine that (-)-zampanolide has similar potency and efficacy to paclitaxel in TNBC cell lines, but …

Preclinical Characterization And Target Validation Of The Antimalarial Pantothenamide Mmv693183., Laura E. De Vries, Patrick A. M. Jansen, Catalina Barcelo, Justin Munro, Julie M. J. Verhoef, Charisse Flerida A. Pasaje, Kelly Rubiano, Josefine Striepen, Nada Abla, Luuk Berning, Judith M. Bolscher, Claudia Demarta-Gatsi, Rob W. M. Henderson, Tonnie Huijs, Karin M J Koolen, Patrick K. Tumwebaze, Tomas Yeo, Anna C. C. Aguiar, Iñigo Angulo-Barturen, Alisje Churchyard, Jake Baum, Benigno Crespo Fernández, Aline Fuchs, Francisco-Javier Gamo, Rafael V. C. Guido, María Belén Jiménez-Diaz, Dhelio B. Pereira, Rosemary Rochford, Camille Roesch, Laura M. Sanz, Graham Trevitt, Benoit Witkowski, Sergio Wittlin, Roland A. Cooper, Philip J. Rosenthal, Robert W. Sauerwein, Joost Schalkwijk, Pedro H. H. Hermkens, Roger V. Bonnert, Brice Campo, David A. Fidock, Manuel Llinás, Jacquin C. Niles, Taco W. A. Kooij, Koen J. Dechering

Natural Sciences and Mathematics | Faculty Scholarship

Drug resistance and a dire lack of transmission-blocking antimalarials hamper malaria elimination. Here, we present the pantothenamide MMV693183 as a first-in-class acetyl-CoA synthetase (AcAS) inhibitor to enter preclinical development. Our studies demonstrate attractive drug-like properties and in vivo efficacy in a humanized mouse model of Plasmodium falciparum infection. The compound shows single digit nanomolar in vitro activity against P. falciparum and P. vivax clinical isolates, and potently blocks P. falciparum transmission to Anopheles mosquitoes. Genetic and biochemical studies identify AcAS as the target of the MMV693183-derived antimetabolite, CoA-MMV693183. Pharmacokinetic-pharmacodynamic modelling predict that a single 30 mg oral dose is sufficient …

Life Stage And Proximity To Roads Shape The Skin Microbiota Of Eastern Newts (Notophthalmus Viridescens), Vanessa P. Wuerthner, Jessica Hua, Obed Hernandez-Gomez

Natural Sciences and Mathematics | Faculty Scholarship

Host-associated microbiomes play an essential role in the health of organisms, including immune system activation, metabolism, and energy uptake. It is well established that microbial communities differ depending on the life stage and natural history of the organism. However, the effects of life stage and natural history on microbial communities may also be influenced by human activities. We investigated the effects of amphibian life stage (terrestrial eft vs. aquatic adult) and proximity to roadways on newt skin bacterial communities. We found that the eft and adult life stages differed in bacterial community composition; however, the effects of roads on community …

Re-Evaluation Of The Fijianolide/Laulimalide Chemotype Suggests An Alternate Mechanism Of Action For C-15/C-20 Analogs., Joseph D. Morris, Leila Takahashi-Ruiz, Lauren N. Persi, Jonathan C. Summers, Erin P. Mccauley, Peter Y. W. Chan, Gabriella Amberchan, Itzel Lizama-Chamu, David A. Coppage, Phillip Crews, April L. Risinger, Tyler A. Johnson

Natural Sciences and Mathematics | Faculty Scholarship

Herein, we report on naturally derived microtubule stabilizers with activity against triple negative breast cancer (TNBC) cell lines, including paclitaxel, fijianolide B/laulimalide (3), fijianolide B di-acetate (4), and two new semisynthetic analogs of 3, which include fijianolide J (5) and fijianolide L (6). Similar to paclitaxel, compound 3 demonstrated classic microtubule stabilizing activity with potent (GI50 = 0.7–17 nM) antiproliferative efficacy among the five molecularly distinct TNBC cell lines. Alternatively, compounds 5 or 6, generated from oxidation of C-20 or C-15 and C-20 respectively, resulted in a unique profile with …

Discovery And Preclinical Pharmacology Of Ine963, A Potent And Fast-Acting Blood-Stage Antimalarial With A High Barrier To Resistance And Potential For Single-Dose Cures In Uncomplicated Malaria., Benjamin R. Taft, Fumiaki Yokokawa, Tom Kirrane, Anne-Catherine Mata, Richard Huang, Nicole Blaquiere, Grace Waldron, Bin Zou, Oliver Simon, Subramanyam Vankadara, Wai Ling Chan, Mei Ding, Sandra Sim, Judith Straimer, Armand Guiguemde, Suresh B Lakshminarayana, Jay Prakash Jain, Christopher Bodenreider, Christopher Thompson, Christian Lanshoeft, Wei Shu, Eric Fang, Jafri Qumber, Katherine Chan, Luying Pei, Yen-Liang Chen, Hanna Schulz, Jessie Lim, Siti Nurdiana Abas, Xiaoman Ang, Yugang Liu, Iñigo Angulo-Barturen, María Belén Jiménez-Díaz, Glaxosmithkline Gamo, Benigno Crespo-Fernandez, Philip J. Rosenthal, Roland A. Cooper, Patrick Tumwebaze, Anna Caroline Campos Aguiar, Brice Campo, Simon Campbell, Jürgen Wagner, Thierry T Diagana, Christopher Sarko

Natural Sciences and Mathematics | Faculty Scholarship

A series of 5-aryl-2-amino-imidazothiadiazole (ITD) derivatives were identified by a phenotype-based high-throughput screening using a blood stage Plasmodium falciparum (Pf) growth inhibition assay. A lead optimization program focused on improving antiplasmodium potency, selectivity against human kinases, and absorption, distribution, metabolism, excretion, and toxicity properties and extended pharmacological profiles culminated in the identification of INE963 (1), which demonstrates potent cellular activity against Pf 3D7 (EC50 = 0.006 μM) and achieves "artemisinin-like" kill kinetics in vitro with a parasite clearance time of/kg is fully curative in the Pf-humanized severe combined immunodeficient mouse model. INE963 (1) also exhibits a high barrier to resistance …

Skin Bacterial Metacommunities Of San Francisco Bay Area Salamanders Are Structured By Host Genus And Habitat Quality., Shannon Buttimer, Obed Hernandez-Gomez, Erica Bree Rosenblum

Natural Sciences and Mathematics | Faculty Scholarship

Host-associated microbial communities can influence physiological processes of macroorganisms, including contributing to infectious disease resistance. For instance, some bacteria that live on amphibian skin produce antifungal compounds that inhibit two lethal fungal pathogens, Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal). Therefore, differences in microbiome composition among host species or populations within a species can contribute to variation in susceptibility to Bd/Bsal. This study applies 16S rRNA sequencing to characterize the skin bacterial microbiomes of three widespread terrestrial salamander genera native to the western United States. Using a metacommunity structure analysis, we identified dispersal barriers for these influential bacteria between salamander …

Can Repurposing Drugs Play A Role In Malaria Control?, Roland A. Cooper, Laura Kirkman

Natural Sciences and Mathematics | Faculty Scholarship

Innovative drug treatments for malaria, optimally with novel targets, are needed to combat the threat of parasite drug resistance. As drug development efforts continue, there may be a role for a host-targeting, repurposed cancer drug administered together with an artemisinin combination therapy that was shown to improve the speed of recovery from a malaria infection.

Associations Between Varied Susceptibilities To Pfatp4 Inhibitors And Genotypes In Ugandan Plasmodium Falciparum Isolates., Oriana Kreutzfeld, Stephanie A. Rasmussen, Aarti A. Ramanathan, Patrick K. Tumwebaze, Oswald Byaruhanga, Thomas Katairo, Victor Asua, Martin Okitwi, Stephen Orena, Jennifer Legac, Melissa D. Conrad, Samuel L. Nsobya, Ozkan Aydemir, Jeffrey Bailey, Maelle Duffey, Brett R. Bayles, Akhil B. Vaidya, Roland A. Cooper, Philip J. Rosenthal

Natural Sciences and Mathematics | Faculty Scholarship

Among novel compounds under recent investigation as potential new antimalarial drugs are three independently developed inhibitors of the Plasmodium falciparum P-type ATPase (PfATP4): KAE609 (cipargamin), PA92, and SJ733. We assessed ex vivo susceptibilities to these compounds of 374 fresh P. falciparum isolates collected in Tororo and Busia districts, Uganda, from 2016 to 2019. Median IC50s were 65 nM for SJ733, 9.1 nM for PA92, and 0.5 nM for KAE609. Sequencing of pfatp4 for 218 of these isolates demonstrated many nonsynonymous single nucleotide polymorphisms; the most frequent mutations were G1128R (69% of isolates mixed or mutant), Q1081K/R (68%), G223S (25%), N1045K …

Drug Susceptibility Of Plasmodium Falciparum In Eastern Uganda: A Longitudinal Phenotypic And Genotypic Study, Patrick K. Tumwebaze, Thomas Katairo, Martin Okitwi, Oswald Byaruhanga, Stephen Orena, Victor Asua, Marvin Duvalsaint, Jennifer Legac, Sevil Chelebieva, Frida G. Ceja, Stephanie A. Rasmussen, Melissa D. Conrad, Samuel L. Nsobya, Ozkan Aydemir, Jeffrey A. Bailey, Brett R. Bayles, Philip J. Rosenthal, Roland A. Cooper

Natural Sciences and Mathematics | Faculty Scholarship

Background: Treatment and control of malaria depends on artemisinin-based combination therapies (ACTs) and is challenged by drug resistance, but thus far resistance to artemisinins and partner drugs has primarily occurred in southeast Asia. The aim of this study was to characterise antimalarial drug susceptibility of Plasmodium falciparum isolates from Tororo and Busia districts in Uganda.

Methods: In this prospective longitudinal study, P falciparum isolates were collected from patients aged 6 months or older presenting at the Tororo District Hospital (Tororo district, a site with relatively low malaria incidence) or Masafu General Hospital (Busia district, a high-incidence site) in eastern Uganda …

The Antimalarial Mmv688533 Provides Potential For Single-Dose Cures With A High Barrier To, James M. Murithi, Cécile Pascal, Jade Bath, Xavier Boulenc, Nina F. Gnädig, Charisse Flerida A. Pasaje, Kelly Rubiano, Tomas Yeo, Sachel Mok, Sylvie Klieber, Paul Desert, María Belén Jiménez-Díaz, Jutta Marfurt, Mélanie Rouillier, Mohammed H. Cherkaoui-Rbati, Nathalie Gobeau, Sergio Wittlin, Anne-Catrin Uhlemann, Ric N. Price, Grennady Wirjanata, Rintis Noviyanti, Patrick Tumwebaze, Roland A. Cooper, Philip J. Rosenthal, Laura M. Sanz, Francisco-Javier Gamo, Jayan Joseph, Shivendra Singh, Sridevi Bashyam, Jean Michel Augereau, Elie Giraud, Tanguy Bozec, Thierry Vermat, Gilles Tuffal, Jean-Michel Guillon, Jérôme Menegotto, Laurent Sallé, Guillaume Louit, Marie-José Cabanis, Marie Françoise Nicolas, Michel Doubovetzky, Rita Merino, Nadir Bessila, Iñigo Angulo-Barturen, Delphine Baud, Lidiya Bebrevska, Fanny Escudié, Jacquin C. Niles, Benjamin Blasco, Simon Campbell, Gilles Courtemanche, Laurent Fraisse, Alain Pellet, David A. Fidock, Didier Leroy

Natural Sciences and Mathematics | Faculty Scholarship

The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in …

The Antimalarial Mmv688533 Provides Potential For Single-Dose Cures With A High Barrier To, James M. Murithi, Cécile Pascal, Jade Bath, Xavier Boulenc, Nina F. Gnädig, Charisse Flerida A. Pasaje, Kelly Rubiano, Tomas Yeo, Sachel Mok, Sylvie Klieber, Paul Desert, María Belén Jiménez-Díaz, Jutta Marfurt, Mélanie Rouillier, Mohammed H. Cherkaoui-Rbati, Nathalie Gobeau, Sergio Wittlin, Anne-Catrin Uhlemann, Ric N. Price, Grennady Wirjanata, Rintis Noviyanti, Patrick K. Tumwebaze, Roland A. Cooper, Philip J. Rosenthal, Laura M. Sanz, Francisco-Javier Gamo, Jayan Joseph, Shivendra Singh, Sridevi Bashyam, Jean Michel Augereau, Elie Giraud, Tanguy Bozec, Thierry Vermat, Gilles Tuffal, Jean-Michel Guillon, Jérôme Menegotto, Laurent Sallé, Guillaume Louit, Marie-José Cabanis, Marie Françoise Nicolas, Michel Doubovetzky, Rita Merino, Nadir Bessila, Iñigo Angulo-Barturen, Delphine Baud, Lidiya Bebrevska, Fanny Escudié, Jacquin C. Niles, Benjamin Blasco, Simon Campbell, Gilles Courtemanche, Laurent Fraisse, Alain Pellet, David A. Fidock, Didier Leroy

Natural Sciences and Mathematics | Faculty Scholarship

The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in …

Balanced Impacts Of Fitness And Drug Pressure On The Evolution Of Pfmdr1 Polymorphisms In Plasmodium Falciparum., Marvin Duvalsaint, Melissa D. Conrad, Stephen Tukwasibwe, Patrick K. Tumwebaze, Jennifer Legac, Roland A. Cooper, Philip J. Rosenthal

Natural Sciences and Mathematics | Faculty Scholarship

BACKGROUND: Anti-malarial drug resistance may be limited by decreased fitness in resistant parasites. Important contributors to resistance are mutations in the Plasmodium falciparum putative drug transporter PfMDR1.

METHODS: Impacts on in vitro fitness of two common PfMDR1 polymorphisms, N86Y, which is associated with sensitivity to multiple drugs, and Y184F, which has no clear impact on drug sensitivity, were evaluated to study associations between resistance mediators and parasite fitness, measured as relative growth in competitive culture experiments. NF10 P. falciparum lines engineered to represent all PfMDR1 N86Y and Y184F haplotypes were co-cultured for 40 days, and the genetic make-up of the …

Development Of A Highly Selective Plasmodium Falciparum Proteasome Inhibitor With Anti-Malaria Activity In Humanized Mice., Wenhu Zhan, Hao Zhang, John Ginn, Annie Leung, Yi J. Liu, Mayako Michino, Akinori Toita, Rei Okamoto, Tzu-Tshin Wong, Toshihiro Imaeda, Ryoma Hara, Takafumi Yukawa, Sevil Chelebieva, Patrick K. Tumwebaze, Maria Jose Lafuente-Monasterio, Maria Santos Martinez-Martinez, Jeremie Vendome, Thijs Beuming, Kenjiro Sato, Kazuyoshi Aso, Philip J. Rosenthal, Roland A. Cooper, Peter T Meinke, Carl F. Nathan, Laura A. Kirkman, Gang Lin

Natural Sciences and Mathematics | Faculty Scholarship

Plasmodium falciparum proteasome (Pf20S) inhibitors are active against Plasmodium at multiple stages-erythrocytic, gametocyte, liver, and gamete activation stages-indicating that selective Pf20S inhibitors possess the potential to be therapeutic, prophylactic, and transmission-blocking antimalarials. Starting from a reported compound, we developed a noncovalent, macrocyclic peptide inhibitor of the malarial proteasome with high species selectivity and improved pharmacokinetic properties. The compound demonstrates specific, time-dependent inhibition of the β5 subunit of the Pf20S, kills artemisinin-sensitive and artemisinin-resistant P. falciparum isolates in vitro and reduces parasitemia in humanized, P. falciparum-infected mice.

Use Of Foliar Chemical Treatments To Induce Disease Resistance In Rhododendrons Inoculated With Phytophthora Ramorum, Craig Ramsey, Paul C. Freebury, Debra H. Newman, Wolfgang Schweigkofler, Leland J. Cseke, Steven E. Newman

Natural Sciences and Mathematics | Faculty Scholarship

A field study was conducted at the National Ornamental Research Site at Dominican University California (NORS-DUC). The study goal was to evaluate three chemical inducers applied as foliar treatments for controlling Phytophthora ramorum, on Rhododendron x ‘Cunningham’s White’ nursery plants. The inducers were chlorine dioxide (ElectroBiocide), hydrogen peroxide (OxiDate 2.0), and acibenzolar-s methyl (Actigard). Water samples from the electrostatic sprayer were measured for three physicochemical water properties. Visual assessment of plant foliage, based on the Horsfall- Barratt scale, was conducted at three and five months after chemical treatments. Foliar fluorescence (Fv/Fm) was measured over three dates. The success of P. …

A Novel Bioaugmentation Technique Effectively Increases The Skin-Associated Microbial Diversity Of Captive Eastern Hellbenders, Erin K. Kenison, Obed Hernandez-Gomez, Rod N. Williams

Natural Sciences and Mathematics | Faculty Scholarship

Captive environments are maintained in hygienic ways that lack free-flowing microbes found in animals’ natural environments. As a result, captive animals often have depauperate host-associated microbial communities compared to conspecifics in the wild and may have increased disease susceptibility and reduced immune function. Eastern hellbenders (Cryptobranchus alleganiensis alleganiensis) have suffered precipitous population declines over the past few decades. To bolster populations, eastern hellbenders are reared in captivity before being translocated to the wild. However, the absence of natural microbial reservoirs within the captive environment diminishes the diversity of skin-associated bacteria on hellbender skin and may negatively influence their ability to …

Invasive Vegetation Affects Amphibian Skin Microbiota And Body Condition, Obed Hernandez-Gomez, Allison Q. Byrne, Alex R. Gunderson, Thomas S. Jenkinson, Clay F. Noss, Andrew P. Rothstein, Molly C. Womack, Erica B. Rosenblum

Natural Sciences and Mathematics | Faculty Scholarship

Invasive plants are major drivers of habitat modification and the scale of their impact is increasing globally as anthropogenic activities facilitate their spread. In California, an invasive plant genus of great concern is Eucalyptus. Eucalyptus leaves can alter soil chemistry and negatively affect underground macro- and microbial communities. Amphibians serve as excellent models to evaluate the effect of Eucalyptus invasion on ground-dwelling species as they predate on soil arthropods and incorporate soil microbes into their microbiotas. The skin microbiota is particularly important to amphibian health, suggesting that invasive plant species could ultimately affect amphibian populations. To investigate the potential for …

Plasmodium Falciparum Resistance To A Lead Benzoxaborole Due To Blocked Compound Activation And Altered Ubiquitination Or Sumoylation., Kirthana M. V. Sindhe, Wesley Wu, Jenny Legac, Yong-Kang Zhang, Eric E. Easom, Roland A. Cooper, Jacob J. Plattner, Yvonne R. Freund, Joseph L. Derisi, Philip J. Rosenthal

Natural Sciences and Mathematics | Faculty Scholarship

New antimalarial drugs are needed. The benzoxaborole AN13762 showed excellent activity against cultured Plasmodium falciparum, against fresh Ugandan P. falciparum isolates, and in murine malaria models. To gain mechanistic insights, we selected in vitro for P. falciparum isolates resistant to AN13762. In all of 11 independent selections with 100 to 200 nM AN13762, the 50% inhibitory concentration (IC50) increased from 18-118 nM to 180-890 nM, and whole-genome sequencing of resistant parasites demonstrated mutations in prodrug activation and resistance esterase (PfPARE). The introduction of PfPARE mutations led to a similar level of resistance, and recombinant PfPARE hydrolyzed AN13762 to the benzoxaborole …

Plasmodium Falciparum Resistance To A Lead Benzoxaborole Due To Blocked Compound Activation And Altered Ubiquitination Or Sumoylation., Kirthana M. V. Sindhe, Wesley Wu, Jenny Legac, Yong-Kang Zhang, Eric E. Easom, Roland A. Cooper, Jacob J. Plattner, Yvonne R. Freund, Joseph L. Derisi, Philip J. Rosenthal

Natural Sciences and Mathematics | Faculty Scholarship

New antimalarial drugs are needed. The benzoxaborole AN13762 showed excellent activity against cultured Plasmodium falciparum, against fresh Ugandan P. falciparum isolates, and in murine malaria models. To gain mechanistic insights, we selected in vitro for P. falciparum isolates resistant to AN13762. In all of 11 independent selections with 100 to 200 nM AN13762, the 50% inhibitory concentration (IC50) increased from 18–118 nM to 180–890 nM, and whole-genome sequencing of resistant parasites demonstrated mutations in prodrug activation and resistance esterase (PfPARE). The introduction of PfPARE mutations led to a similar level of resistance, and recombinant PfPARE hydrolyzed AN13762 to the benzoxaborole …

Sources And Toxicity Of Mercury In The San Francisco Bay Area, Spanning California And Beyond., Mietek Kolipinski, Mani Subramanian, Kristina Kristen, Steven Borish, Stacy Ditta

Natural Sciences and Mathematics | Faculty Scholarship

This report synthesizes and evaluates published scientific literature on the environmental occurrence and biomagnification of mercury with emphasis on the San Francisco Bay Area (SFBA), California. Mercury forms various compounds, well known for their toxicity in humans and environmental ecosystems. Elemental mercury is transported and distributed by air, water, and sediments. Through the metabolic processes of algae and bacteria, mercury is converted into organic compounds, such as methylmercury (MeHg), which then bioaccumulates up through trophic levels. In fish, it is found primarily in skeletal muscle, while in humans, the primary target organs are the brain and kidneys. Health concerns exist …

Total Cellular Atp Production Changes With Primary Substrate In Mcf7 Breast Cancer Cells., Maggie Louie, Justin Ton, Maurice L. Brady, Diem T. Le, Jordon N. Mar, Chad A Lerner, Akos A Gerencser, Shona A. Mookerjee

Natural Sciences and Mathematics | Faculty Scholarship

Cancer growth is predicted to require substantial rates of substrate catabolism and ATP turnover to drive unrestricted biosynthesis and cell growth. While substrate limitation can dramatically alter cell behavior, the effects of substrate limitation on total cellular ATP production rate is poorly understood. Here, we show that MCF7 breast cancer cells, given different combinations of the common cell culture substrates glucose, glutamine, and pyruvate, display ATP production rates 1.6-fold higher than when cells are limited to each individual substrate. This increase occurred mainly through faster oxidative ATP production, with little to no increase in glycolytic ATP production. In comparison, non-transformed …

Developmental Transcriptomic Analysis Of The Cave-Dwelling Crustacean, Asellus Aquaticus, Joshua B. Gross, Dennis A. Sun, Brian M. Carlson, Sivan Brodo-Abo, Meredith E. Protas

Natural Sciences and Mathematics | Faculty Scholarship

Cave animals are a fascinating group of species often demonstrating characteristics including reduced eyes and pigmentation, metabolic efficiency, and enhanced sensory systems. Asellus aquaticus, an isopod crustacean, is an emerging model for cave biology. Cave and surface forms of this species differ in many characteristics, including eye size, pigmentation, and antennal length. Existing resources for this species include a linkage map, mapped regions responsible for eye and pigmentation traits, sequenced adult transcriptomes, and comparative embryological descriptions of the surface and cave forms. Our ultimate goal is to identify genes and mutations responsible for the differences between the cave and …

Chronic Cadmium Exposure Decreases The Dependency Of Mcf7 Breast Cancer Cells On Erα., Mathew Bloomfield, Maggie Louie

Natural Sciences and Mathematics | Faculty Scholarship

Cadmium is an environmental contaminant that can activate estrogen receptor alpha (ERα) and contribute to the development and progression of breast cancer. Our lab previously demonstrated that chronic cadmium exposure alters the expression of several ERα-responsive genes and increases the malignancy of breast cancer cells. Although these studies support cadmium's function as a hormone disrupter, the role of ERα in cadmium-induced breast cancer progression remains unclear. To address this, we modulated the expression of ERα and found that while the loss of ERα significantly impaired cancer cell growth, migration, invasion and anchorage-independent growth in both MCF7 and MCF7-Cd cells, cadmium-exposed …

Novel Flexible Heteroarotinoid, Sl-1-39, Inhibits Her2-Positive Breast Cancer Cell Proliferation By Promoting Lysosomal Degradation Of Her2., Hongye Zou, Mary B. Sevigny, Shengquan Liu, David T. Madden, Maggie Louie

Natural Sciences and Mathematics | Faculty Scholarship

SL-1-39 [1-(4-chloro-3-methylphenyl)-3-(4-nitrophenyl)thiourea] is a new flexible heteroarotinoid (Flex-Het) analog derived from the parental compound, SHetA2, previously shown to inhibit cell growth across multiple cancer types. The current study aims to determine growth inhibitory effects of SL-1-39 across the different subtypes of breast cancer cells and delineate its molecular mechanism. Our results demonstrate that while SL-1-39 blocks cell proliferation of all breast cancer subtypes tested, it has the highest efficacy against HER2+ breast cancer cells. Molecular analyses suggest that SL-1-39 prevents S phase progression of HER2+ breast cancer cells (SKBR3 and MDA-MB-453), which is consistent with reduced expression of key cell-cycle …