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Changes In Familiarity With And Willingness To Take Prep In A Longitudinal Study Of Highly Sexually Active Gay And Bisexual Men, Christian Grov, H. Jonathan Rendina, Thomas H.F. Whitfield, Ana Ventuneac, Jeffrey T. Parsons
Changes In Familiarity With And Willingness To Take Prep In A Longitudinal Study Of Highly Sexually Active Gay And Bisexual Men, Christian Grov, H. Jonathan Rendina, Thomas H.F. Whitfield, Ana Ventuneac, Jeffrey T. Parsons
Publications and Research
PURPOSE: For gay and bisexual men (GBM), research suggests that familiarity with Pre-Exposure Prophylaxis (PrEP) has been increasing since being approved by the U.S. FDA in 2012. However, it is less clear how willingness to start using PrEP has changed over time. Likewise, some have expressed concerns regarding the potential for risk compensation (i.e., reduced condom use) were one to start PrEP; however, again, it is unclear how these may have been changing over time.
METHODS: We conducted baseline and 12 month assessments with 158 highly sexually active HIV-negative GBM in NYC who were assessed between 2011 and 2014. …
Biomechanical Performances Of Networked Polyethylene Glycol Diacrylate: Effect Of Photoinitiator Concentration, Temperature, And Incubation Time, Morshed Khandaker, Albert Orock, Stefano Tarantini, Jeremiah White, Ozlem Yasar
Biomechanical Performances Of Networked Polyethylene Glycol Diacrylate: Effect Of Photoinitiator Concentration, Temperature, And Incubation Time, Morshed Khandaker, Albert Orock, Stefano Tarantini, Jeremiah White, Ozlem Yasar
Publications and Research
Nutrient conduit networks can be introduced within the Polyethylene Glycol Diacrylate (PEGDA) tissue construct to enable cells to survive in the scaffold. Nutrient conduit networks can be created on PEGDA by macrochannel to nanochannel fabrication techniques. Such networks can influence the mechanical and cell activities of PEGDA scaffold. There is no study conducted to evaluate the effect of nutrient conduit networks on the maximum tensile stress and cell activities of the tissue scaffold.The study aimed to explore the influence of the network architecture on the maximum tensile stress of PEGDA scaffold and compared with the nonnetworked PEGDA scaffold. Our study …
The Effect Of Ultralow-Dose Antibiotics Exposure On Soil Nitrate And N2o Flux, Stephanie L. Devries, Madeline Loving, Xiqing Li, Pengfei Zhang
The Effect Of Ultralow-Dose Antibiotics Exposure On Soil Nitrate And N2o Flux, Stephanie L. Devries, Madeline Loving, Xiqing Li, Pengfei Zhang
Publications and Research
Exposure to sub-inhibitory concentrations of antibiotics has been shown to alter the metabolic activity of micro-organisms, but the impact on soil denitrification and N2O production has rarely been reported. In this study, incubation and column transport experiments were conducted on soils exposed to as many as four antibiotics in the ng·kg−1 range (several orders of magnitude below typical exposure rates) to evaluate the impact of ultralow dose exposure on net nitrate losses and soil N2O flux over time. Under anaerobic incubation conditions, three antibiotics produced statistically significant dose response curves in which denitrification was stimulated at some doses and inhibited …
The Clustered Protocadherin Endolysosomal Trafficking Motif Mediates Cytoplasmic Association, Adam Shonubi, Chantelle Roman, Greg R. Phillips
The Clustered Protocadherin Endolysosomal Trafficking Motif Mediates Cytoplasmic Association, Adam Shonubi, Chantelle Roman, Greg R. Phillips
Publications and Research
Background Clustered protocadherins (Pcdhs) are a large family of neural cadherin-like proteins encoded by individual exons located within three gene clusters. Each exon codes an extracellular, transmembrane, and proximal cytoplasmic domain. These “variable” regions may be spliced to a constant cytoplasmic moiety encoded at the end of a cluster. Pcdh extracellular domains mediate homophilic cell-cell binding but their cytoplasmic domains cause intracellular retention and may negatively regulate Pcdh cell-cell binding. Pcdhs can be found at the cell surface in neurons and other cells but are also, unlike classical cadherins, prominently trafficked to the endolysosome system. It was previously found that …
The Mathematics And Applications Behind Image Warping And Morphing, Tanvir Prince, Maria Malik, Ildefonso Salva, Ariel Mazor, Sakhr Aldaylam
The Mathematics And Applications Behind Image Warping And Morphing, Tanvir Prince, Maria Malik, Ildefonso Salva, Ariel Mazor, Sakhr Aldaylam
Publications and Research
This research is conducted in the summer of 2015 and is possible by the support of various agency, in particular, by the grant of Prof. Angulo Nieves and the New York City Research Initiative.
The purpose of this research is to reveal the mathematics and applications of the computer animation techniques of warping and morphing. A warp is a twist or distortion in the form of an object in an image while a morph is the smooth and gradual transformation of an object in one image into the object in another image. Linear algebra makes these computer animation techniques possible; …
Cortical Components Of Reaction-Time During Perceptual Decisions In Humans, Jacek P. Dmochowski, Anthony M. Norcia
Cortical Components Of Reaction-Time During Perceptual Decisions In Humans, Jacek P. Dmochowski, Anthony M. Norcia
Publications and Research
The mechanisms of perceptual decision-making are frequently studied through measurements of reaction time (RT). Classical sequential-sampling models (SSMs) of decision-making posit RT as the sum of non-overlapping sensory, evidence accumulation, and motor delays. In contrast, recent empirical evidence hints at a continuous-flow paradigm in which multiple motor plans evolve concurrently with the accumulation of sensory evidence. Here we employ a trial-to-trial reliability-based component analysis of encephalographic data acquired during a random-dot motion task to directly image continuous flow in the human brain. We identify three topographically distinct neural sources whose dynamics exhibit contemporaneous ramping to time-of-response, with the rate and …
Word-Length Correlations And Memory In Large Texts: A Visibility Network Analysis, Lev Guzmán-Vargas, Bibiana Obregón-Quintana, Daniel Aguilar-Velázquez, Ricardo Hernández-Pérez, Larry S. Liebovitch
Word-Length Correlations And Memory In Large Texts: A Visibility Network Analysis, Lev Guzmán-Vargas, Bibiana Obregón-Quintana, Daniel Aguilar-Velázquez, Ricardo Hernández-Pérez, Larry S. Liebovitch
Publications and Research
We study the correlation properties of word lengths in large texts from 30 ebooks in the English language from the Gutenberg Project (www.gutenberg.org) using the natural visibility graph method (NVG). NVG converts a time series into a graph and then analyzes its graph properties. First, the original sequence of words is transformed into a sequence of values containing the length of each word, and then, it is integrated. Next, we apply the NVG to the integrated word-length series and construct the network. We show that the degree distribution of that network follows a power law, P(k)∼k−γP(k)∼k-γ, with two regimes, which …
In Vitro And In Vivo Evaluation Of Water-Soluble Iminophosphorane Ruthenium(Ii) Compounds. A Potential Chemotherapeutic Agent For Triple Negative Breast Cancer, Malgorzata Frik, Alberto Martínez, Benelita T. Elie, Oscar Gonzalo, Daniel Ramírez De Mingo, Mercedes Sanaú, Roberto Sánchez-Delgado, Tanmoy Sadhukha, Swayam Prabha, Joe W. Ramos, Isabel Marzo, María Contel
In Vitro And In Vivo Evaluation Of Water-Soluble Iminophosphorane Ruthenium(Ii) Compounds. A Potential Chemotherapeutic Agent For Triple Negative Breast Cancer, Malgorzata Frik, Alberto Martínez, Benelita T. Elie, Oscar Gonzalo, Daniel Ramírez De Mingo, Mercedes Sanaú, Roberto Sánchez-Delgado, Tanmoy Sadhukha, Swayam Prabha, Joe W. Ramos, Isabel Marzo, María Contel
Publications and Research
A series of organometallic ruthenium(II) complexes containing iminophosphorane ligands have been synthesized and characterized. Cationic compounds with chloride as counterion are soluble in water (70–100 mg/mL). Most compounds (especially highly water-soluble 2) are more cytotoxic to a number of human cancer cell lines than cisplatin. Initial mechanistic studies indicate that the cell death type for these compounds is mainly through canonical or caspase-dependent apoptosis, nondependent on p53, and that the compounds do not interact with DNA or inhibit protease cathepsin B. In vivo experiments of 2 on MDA-MB-231 xenografts in NOD.CB17-Prkdc SCID/J mice showed an impressive tumor reduction (shrinkage) of …
The New York Head—A Precise Standardized Volume Conductor Model For Eeg Source Localization And Tes Targeting, Yu Huang, Lucas C. Parra, Stefan Haufe
The New York Head—A Precise Standardized Volume Conductor Model For Eeg Source Localization And Tes Targeting, Yu Huang, Lucas C. Parra, Stefan Haufe
Publications and Research
In source localization of electroencephalograpic (EEG) signals, as well as in targeted transcranial electric current stimulation (tES), a volume conductor model is required to describe the flow of electric currents in the head. Boundary element models (BEM) can be readily computed to representmajor tissue compartments, but cannot encode detailed anatomical information within compartments. Finite element models (FEM) can capture more tissue types and intricate anatomical structures, but with the higher precision also comes the need for semiautomated segmentation, and a higher computational cost. In either case, adjusting to the individual human anatomy requires costlymagnetic resonance imaging (MRI), and thus head …
Environmental Enrichment Increases Glucocorticoid Receptors And Decreases Glua2 And Protein Kinase M Zeta (Pkmζ) Trafficking During Chronic Stress: A Protective Mechanism?, Roseanna M. Zanca, Stephen H. Braren, Brigid Maloney, Lisa M. Schrott, Victoria N. Luine, Peter A. Serrano
Environmental Enrichment Increases Glucocorticoid Receptors And Decreases Glua2 And Protein Kinase M Zeta (Pkmζ) Trafficking During Chronic Stress: A Protective Mechanism?, Roseanna M. Zanca, Stephen H. Braren, Brigid Maloney, Lisa M. Schrott, Victoria N. Luine, Peter A. Serrano
Publications and Research
Environmental enrichment (EE) housing paradigms have long been shown beneficial for brain function involving neural growth and activity, learning and memory capacity, and for developing stress resiliency. The expression of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluA2, which is important for synaptic plasticity and memory, is increased with corticosterone (CORT), undermining synaptic plasticity and memory. Thus, we determined the effect of EE and stress on modulating GluA2 expression in Sprague-Dawley male rats. Several markers were evaluated which include: plasma CORT, the glucocorticoid receptor (GR), GluA2, and the atypical protein kinase M zeta (PKMζ). For 1 week standard-(ST) or EE-housed animals …
Adaptive Evolution Of Eel Fluorescent Proteins From Fatty Acid Binding Proteins Produces Bright Fluorescence In The Marine Environment, David F. Gruber, Jean P. Gaffney, Shaadi Mehr, Rob Desalle, John S. Sparks, Jelena Platisa, Vincent A. Pieribone
Adaptive Evolution Of Eel Fluorescent Proteins From Fatty Acid Binding Proteins Produces Bright Fluorescence In The Marine Environment, David F. Gruber, Jean P. Gaffney, Shaadi Mehr, Rob Desalle, John S. Sparks, Jelena Platisa, Vincent A. Pieribone
Publications and Research
We report the identification and characterization of two new members of a family of bilirubin-inducible fluorescent proteins (FPs) from marine chlopsid eels and demonstrate a key region of the sequence that serves as an evolutionary switch from non-fluorescent to fluorescent fatty acid-binding proteins (FABPs). Using transcriptomic analysis of two species of brightly fluorescent Kaupichthys eels (Kaupichthys hyoproroides and Kaupichthys n. sp.), two new FPs were identified, cloned and characterized (Chlopsid FP I and Chlopsid FP II). We then performed phylogenetic analysis on 210 FABPs, spanning 16 vertebrate orders, and including 163 vertebrate taxa. We show that the fluorescent FPs diverged …
Case Studies And Pervasive Instruction: Using Journalism Education Techniques In The Information Literacy Classroom, Jennifer Noe
Case Studies And Pervasive Instruction: Using Journalism Education Techniques In The Information Literacy Classroom, Jennifer Noe
Publications and Research
The purpose of this paper is to explore whether journalism education techniques can be adapted for use in the information literacy classroom as a means of teaching the ethical use of information. The author uses personal experience as a journalist and graduate of journalism education programs to examine the similarities between journalism pedagogy and information literacy and whether any aspect of journalism pedagogy is transferrable to the information literacy classroom.
Rag-3d: A Search Tool For Rna 3d Substructures, Mai Zahran, Cigdem Sevim Bayrak, Shereef Elmetwaly, Tamar Schlick
Rag-3d: A Search Tool For Rna 3d Substructures, Mai Zahran, Cigdem Sevim Bayrak, Shereef Elmetwaly, Tamar Schlick
Publications and Research
To address many challenges in RNA structure/function prediction, the characterization of RNA's modular architectural units is required. Using the RNA-As-Graphs (RAG) database, we have previously explored the existence of secondary structure (2D) submotifs within larger RNA structures. Here we present RAG-3D—a dataset of RNA tertiary (3D) structures and substructures plus a web-based search tool—designed to exploit graph representations of RNAs for the goal of searching for similar 3D structural fragments. The objects in RAG-3D consist of 3D structures translated into 3D graphs, cataloged based on the connectivity between their secondary structure elements. Each graph is additionally described in terms of …
Organometallic Titanocene–Gold Compounds As Potential Chemotherapeutics In Renal Cancer. Study Of Their Protein Kinase Inhibitory Properties, Jacob Fernández-Gallardo, Benelita T. Elie, Florian J. Sulzmaier, Mercedes Sanaú, Joe W. Ramos, María Contel
Organometallic Titanocene–Gold Compounds As Potential Chemotherapeutics In Renal Cancer. Study Of Their Protein Kinase Inhibitory Properties, Jacob Fernández-Gallardo, Benelita T. Elie, Florian J. Sulzmaier, Mercedes Sanaú, Joe W. Ramos, María Contel
Publications and Research
Early–late transition metal TiAu2 compounds [(η-C5H5)2Ti{OC(O)CH2PPh2AuCl}2] (3) and new [(η-C5H5)2Ti{OC(O)-4-C6H4PPh2AuCl}2] (5) were evaluated as potential anticancer agents in vitro against renal and prostate cancer cell lines. The compounds were significantly more effective than monometallic titanocene dichloride and gold(I) [{HOC(O)RPPh2}AuCl] (R = −CH2– 6, −4-C6H4– 7) derivatives in renal cancer cell lines, indicating a synergistic effect of the resulting heterometallic species. The activity on renal cancer cell lines (for 5 in the nanomolar range) was considerably higher than that of cisplatin and highly active titanocene Y. Initial mechanistic studies in Caki-1 cells in vitro coupled with studies of their inhibitory properties …
In Vitro Mutational And Bioinformatics Analysis Of The M71 Odorant Receptor And Its Superfamily, Jaclyn Bubnell, Sophie Jamet, Delia Tomoiaga, Charlotte D’Hulst, Konstantinos Krampis, Paul Feinstein
In Vitro Mutational And Bioinformatics Analysis Of The M71 Odorant Receptor And Its Superfamily, Jaclyn Bubnell, Sophie Jamet, Delia Tomoiaga, Charlotte D’Hulst, Konstantinos Krampis, Paul Feinstein
Publications and Research
We performed an extensive mutational analysis of the canonical mouse odorant receptor (OR) M71 to determine the properties of ORs that inhibit plasma membrane trafficking in heterologous expression systems. We employed the use of the M71::GFP fusion protein to directly assess plasma membrane localization and functionality of M71 in heterologous cells in vitro or in olfactory sensory neurons (OSNs) in vivo. OSN expression of M71::GFP show only small differences in activity compared to untagged M71. However, M71::GFP could not traffic to the plasma membrane even in the presence of proposed accessory proteins RTP1S or mβ2AR. To ask if ORs contain …
In Vitro Mutational Analysis Of The Β2 Adrenergic Receptor, An In Vivo Surrogate Odorant Receptor, Sophie Jamet, Jaclyn Bubnell, Patrick Pfister, Delia Tomoiaga, Matthew E. Rogers, Paul Feinstein
In Vitro Mutational Analysis Of The Β2 Adrenergic Receptor, An In Vivo Surrogate Odorant Receptor, Sophie Jamet, Jaclyn Bubnell, Patrick Pfister, Delia Tomoiaga, Matthew E. Rogers, Paul Feinstein
Publications and Research
Many G-protein coupled receptors (GPCRs), such as odorant receptors (ORs), cannot be characterized in heterologous cells because of their difficulty in trafficking to the plasma membrane. In contrast, a surrogate OR, the GPCR mouse β2-adrenergic-receptor (mβ2AR), robustly traffics to the plasma membrane. We set out to characterize mβ2AR mutants in vitro for their eventual use in olfactory axon guidance studies. We performed an extensive mutational analysis of mβ2AR using a Green Fluorescent Protein-tagged mβ2AR (mβ2AR::GFP) to easily assess the extent of its plasma membrane localization. In order to characterize mutants for their ability to successfully transduce ligand-initiated signal cascades, we …
Spatial Associations Between Contaminated Land And Socio Demographics In Ghana, Russell Dowling, Bret Ericson, Jack Caravanos, Patrick Grigsby, Yaw Amoyaw-Osei
Spatial Associations Between Contaminated Land And Socio Demographics In Ghana, Russell Dowling, Bret Ericson, Jack Caravanos, Patrick Grigsby, Yaw Amoyaw-Osei
Publications and Research
Associations between contaminated land and socio demographics are well documented in high-income countries. In low- and middle-income countries, however, little is known about the extent of contaminated land and possible demographic correlations. This is an important yet sparsely researched topic with potentially significant public health implications as exposure to pollution remains a leading source of morbidity and mortality in low-income countries. In this study, we review the associations between several socio demographic factors (population, population density, unemployment, education, and literacy) and contaminated sites in Ghana. Within this context, both correlation and association intend to show the relationship between two variables, …
Size Does Matter: Crocodile Mothers React More To The Voice Of Smaller Offspring, T. Chabert, A. Colin, T. Aubin, V. Shacks, S. L. Bourquin, R. M. Elsey, J. G. Acosta, N. Mathevon
Size Does Matter: Crocodile Mothers React More To The Voice Of Smaller Offspring, T. Chabert, A. Colin, T. Aubin, V. Shacks, S. L. Bourquin, R. M. Elsey, J. G. Acosta, N. Mathevon
Publications and Research
Parental care is widespread in Archosaurs (birds, crocodilians, dinosaurs and pterosaurs), and this group provides a useful model for the evolution of parent-offspring interactions. While offspring signalling has been well-studied in birds, the modulation of parental care in crocodilians remains an open question. Here we show that acoustic communication has a key role in the dynamics of crocodilian’ mother-offspring relationships. We found embedded information about the emitter’s size in juvenile calls of several species, and experimentally demonstrated that Nile crocodile mothers breeding in the wild are less receptive to the calls of larger juveniles. Using synthetized sounds, we further showed …
Daily Minority Stress And Affect Among Gay And Bisexual Men: A 30-Day Diary Study, Adam I. Eldahan, John E. Pachankis, H. Jonathan Rendina, Ana Ventuneac, Christian Grov, Jeffrey T. Parsons
Daily Minority Stress And Affect Among Gay And Bisexual Men: A 30-Day Diary Study, Adam I. Eldahan, John E. Pachankis, H. Jonathan Rendina, Ana Ventuneac, Christian Grov, Jeffrey T. Parsons
Publications and Research
Background. This study examined the time-variant association between daily minority stress and daily affect among gay and bisexual men. Tests of time-lagged associations allow for a stronger causal examination of minority stress-affect associations compared with static assessments. Multilevel modeling allows for comparison of associations between minority stress and daily affect when minority stress is modeled as a between-person factor and a within-person time-fluctuating state.
Methods. 371 gay and bisexual men in New York City completed a 30-day daily diary, recording daily experiences of minority stress and positive affect (PA), negative affect (NA), and anxious affect (AA). Multilevel analyses examined …
Supporting Teachers’ Learning About Mathematical Modeling, June L. Gastón, Barbara A. Lawrence
Supporting Teachers’ Learning About Mathematical Modeling, June L. Gastón, Barbara A. Lawrence
Publications and Research
In the United States, one of the Standards for Mathematical Practice of the Common Core Curriculum (Common Core State Standards Initiative, 2010) is Model with mathematics. This standard requires that students be taught in a manner that will enable them to ―apply the mathematics they know to solve problems arising in everyday life, society, and the workplace‖ (p. 7). However many prospective and practicing teachers acquire a pedagogical style that does not support this standard. To promote higher levels of student thinking associated with mathematical modeling, teachers must thus be taught not only what mathematical modeling is, but how it …
Antimicrobial Copper Alloy Surfaces Are Effective Against Vegetative But Not Sporulated Cells Of Gram-Positive Bacillus Subtilis, Kaungmyat San, Janet Long, Corinne A. Michels, Nidhi Gadura
Antimicrobial Copper Alloy Surfaces Are Effective Against Vegetative But Not Sporulated Cells Of Gram-Positive Bacillus Subtilis, Kaungmyat San, Janet Long, Corinne A. Michels, Nidhi Gadura
Publications and Research
This study explores the role of membrane phospholipid peroxidation in the copper alloy mediated contact killing of Bacillus subtilis, a spore-forming gram-positive bacterial species. We found that B. subtilis endospores exhibited significant resistance to copper alloy surface killing but vegetative cells were highly sensitive to copper surface exposure. Cell death and lipid peroxidation occurred in B. subtilis upon copper alloy surface exposure. In a sporulation-defective strain carrying a deletion of almost the entire SpoIIA operon, lipid peroxidation directly correlated with cell death. Moreover, killing and lipid peroxidation initiated immediately and at a constant rate upon exposure to the copper surface …
Synthesis Of New 4-Aminoquinolines And Evaluation Of Their In Vitro Activity Against Chloroquine-Sensitive And Chloroquine-Resistant Plasmodium Falciparum, Chandima S. K. Rajapakse, Maryna Lisai, Christiane Deregnaucourt, Véronique Sinou, Christine Latour, Dipankar Roy, Joseph Schrével, Roberto A. Sánchez-Delgado
Synthesis Of New 4-Aminoquinolines And Evaluation Of Their In Vitro Activity Against Chloroquine-Sensitive And Chloroquine-Resistant Plasmodium Falciparum, Chandima S. K. Rajapakse, Maryna Lisai, Christiane Deregnaucourt, Véronique Sinou, Christine Latour, Dipankar Roy, Joseph Schrével, Roberto A. Sánchez-Delgado
Publications and Research
The efficacy of chloroquine, once the drug of choice in the fight against Plasmodium falciparum, is now severely limited due to widespread resistance. Amodiaquine is one of the most potent antimalarial 4-aminoquinolines known and remains effective against chloroquine-resistant parasites, but toxicity issues linked to a quinone-imine metabolite limit its clinical use. In search of new compounds able to retain the antimalarial activity of amodiaquine while circumventing quinone-imine metabolite toxicity, we have synthesized five 4-aminoquinolines that feature rings lacking hydroxyl groups in the side chain of the molecules and are thus incapable of generating toxic quinone-imines. The new compounds displayed high …
Molecular Phylogenetics Reveals Convergent Evolution In Lower Congo River Spiny Eels, S. Elizabeth Alter, Bianca Brown, Melanie L. J. Stiassny
Molecular Phylogenetics Reveals Convergent Evolution In Lower Congo River Spiny Eels, S. Elizabeth Alter, Bianca Brown, Melanie L. J. Stiassny
Publications and Research
Background The lower Congo River (LCR) is a region of exceptional species diversity and endemism in the Congo basin, including numerous species of spiny eels (genus Mastacembelus). Four of these exhibit distinctive phenotypes characterized by greatly reduced optic globes deeply embedded into the head (cryptophthalmia) and reduced (or absent) melanin pigmentation, among other characteristics. A strikingly similar cryptophthalmic phenotype is also found in members of a number of unrelated fish families, strongly suggesting the possibility of convergent evolution. However, little is known about the evolutionary processes that shaped diversification in LCR Mastacembelus, their biogeographic origins, or when colonization of the …
Bats, Trypanosomes, And Triatomines In Ecuador: New Insights Into The Diversity, Transmission, And Origins Of Trypanosoma Cruzi And Chagas Disease, C. Miguel Pinto, Sofía Ocaña-Mayorga, Elicio E. Tapia, Simón E. Lobos, Alejandra P. Zurita, Fernanda Aguirre-Villacís, Amber Macdonald, Anita G. Villacís, Luciana Lima, Marta M. G. Teixeira, Mario J. Grijalva, Susan L. Perkins
Bats, Trypanosomes, And Triatomines In Ecuador: New Insights Into The Diversity, Transmission, And Origins Of Trypanosoma Cruzi And Chagas Disease, C. Miguel Pinto, Sofía Ocaña-Mayorga, Elicio E. Tapia, Simón E. Lobos, Alejandra P. Zurita, Fernanda Aguirre-Villacís, Amber Macdonald, Anita G. Villacís, Luciana Lima, Marta M. G. Teixeira, Mario J. Grijalva, Susan L. Perkins
Publications and Research
The generalist parasite Trypanosoma cruzi has two phylogenetic lineages associated almost exclusively with bats—Trypanosoma cruzi Tcbat and the subspecies T. c. marinkellei. We present new information on the genetic variation, geographic distribution, host associations, and potential vectors of these lineages. We conducted field surveys of bats and triatomines in southern Ecuador, a country endemic for Chagas disease, and screened for trypanosomes by microscopy and PCR. We identified parasites at species and genotype levels through phylogenetic approaches based on 18S ribosomal RNA (18S rRNA) and cytochrome b (cytb) genes and conducted a comparison of nucleotide diversity of the cytb gene. We …
Comparing Species Tree Estimation With Large Anchored Phylogenomic And Small Sanger-Sequenced Molecular Datasets: An Empirical Study On Malagasy Pseudoxyrhophiine Snakes, Sara Ruane, Christopher J. Raxworthy, Alan R. Lemmon, Emily Moriarty Lemmon, Frank T. Burbrink
Comparing Species Tree Estimation With Large Anchored Phylogenomic And Small Sanger-Sequenced Molecular Datasets: An Empirical Study On Malagasy Pseudoxyrhophiine Snakes, Sara Ruane, Christopher J. Raxworthy, Alan R. Lemmon, Emily Moriarty Lemmon, Frank T. Burbrink
Publications and Research
Background Using molecular data generated by high throughput next generation sequencing (NGS) platforms to infer phylogeny is becoming common as costs go down and the ability to capture loci from across the genome goes up. While there is a general consensus that greater numbers of independent loci should result in more robust phylogenetic estimates, few studies have compared phylogenies resulting from smaller datasets for commonly used genetic markers with the large datasets captured using NGS. Here, we determine how a 5-locus Sanger dataset compares with a 377-locus anchored genomics dataset for understanding the evolutionary history of the pseudoxyrhophiine snake radiation …
Cladribine Analogues Via O6-(Benzotriazolyl) Derivatives Of Guanine Nucleosides, Sakilam Satishkumar, Prasanna K. Vuram, Siva Subrahmanyam Relangi, Venkateshwarlu Gurram, Hong Zhou, Robert J. Kreitman, Michelle M. Martínez Montemayor, Lijia Yang, Muralidharan Kaliyaperumal, Somesh Sharma, Narender Pottabathini, Mahesh K. Lakshman
Cladribine Analogues Via O6-(Benzotriazolyl) Derivatives Of Guanine Nucleosides, Sakilam Satishkumar, Prasanna K. Vuram, Siva Subrahmanyam Relangi, Venkateshwarlu Gurram, Hong Zhou, Robert J. Kreitman, Michelle M. Martínez Montemayor, Lijia Yang, Muralidharan Kaliyaperumal, Somesh Sharma, Narender Pottabathini, Mahesh K. Lakshman
Publications and Research
Cladribine, 2-chloro-2′-deoxyadenosine, is a highly efficacious, clinically used nucleoside for the treatment of hairy cell leukemia. It is also being evaluated against other lymphoid malignancies and has been a molecule of interest for well over half a century. In continuation of our interest in the amide bond-activation in purine nucleosides via the use of (benzotriazol-1yl-oxy)tris(dimethylamino)phosphonium hexafluorophosphate, we have evaluated the use of O6-(benzotriazol-1-yl)-2′-deoxyguanosine as a potential precursor to cladribine and its analogues. These compounds, after appropriate deprotection, were assessed for their biological activities, and the data are presented herein. Against hairy cell leukemia (HCL), T-cell lymphoma (TCL) and chronic lymphocytic …
Effect Of Relative Arrangement Of Cationic And Lipophilic Moieties On Hemolytic And Antibacterial Activities Of Pegylated Polyacrylates, Ashish Punia, Kevin Lee, Edward He, Sumit Mukherjee, Andrew Mancuso, Probal Banerjee, Nan-Loh Yang
Effect Of Relative Arrangement Of Cationic And Lipophilic Moieties On Hemolytic And Antibacterial Activities Of Pegylated Polyacrylates, Ashish Punia, Kevin Lee, Edward He, Sumit Mukherjee, Andrew Mancuso, Probal Banerjee, Nan-Loh Yang
Publications and Research
Synthetic amphiphilic polymers have been established as potentially efficient agents to combat widespread deadly infections involving antibiotic resistant superbugs. Incorporation of poly(ethylene glycol) (PEG) side chains into amphiphilic copolymers can reduce their hemolytic activity while maintaining high antibacterial activity. Our study found that the incorporation of PEG has substantially different effects on the hemolytic and antibacterial activities of copolymers depending on structural variations in the positions of cationic centers relative to hydrophobic groups. The PEG side chains dramatically reduced the hemolytic activities in copolymers with hydrophobic hexyl and cationic groups on the same repeating unit. However, in case of terpolymers …
Developing A Dissociative Nanocontainer For Peptide Drug Delivery, Patrick Kelly, Prachi Anand, Alexander Uvaydov, Srinivas Chakravartula, Chhime Sherpa, Elena Pires, Alison O’Neil, Trevor Douglas, Mandë Holford
Developing A Dissociative Nanocontainer For Peptide Drug Delivery, Patrick Kelly, Prachi Anand, Alexander Uvaydov, Srinivas Chakravartula, Chhime Sherpa, Elena Pires, Alison O’Neil, Trevor Douglas, Mandë Holford
Publications and Research
The potency, selectivity, and decreased side effects of bioactive peptides have propelled these agents to the forefront of pharmacological research. Peptides are especially promising for the treatment of neurological disorders and pain. However, delivery of peptide therapeutics often requires invasive techniques, which is a major obstacle to their widespread application. We have developed a tailored peptide drug delivery system in which the viral capsid of P22 bacteriophage is modified to serve as a tunable nanocontainer for the packaging and controlled release of bioactive peptides. Recent efforts have demonstrated that P22 nanocontainers can effectively encapsulate analgesic peptides and translocate them across …
Two Distinct Modes Of Metal Ion Binding In The Nuclease Active Site Of A Viral Dna-Packaging Terminase: Insight Into The Two-Metal-Ion Catalytic Mechanism, Haiyan Zhao, Zihan Lin, Anna Y. Lynn, Brittany Varnado, John A. Beutler, Ryan P. Murelli, Stuart F.J. Le Grice, Liang Tang
Two Distinct Modes Of Metal Ion Binding In The Nuclease Active Site Of A Viral Dna-Packaging Terminase: Insight Into The Two-Metal-Ion Catalytic Mechanism, Haiyan Zhao, Zihan Lin, Anna Y. Lynn, Brittany Varnado, John A. Beutler, Ryan P. Murelli, Stuart F.J. Le Grice, Liang Tang
Publications and Research
Many dsDNA viruses encode DNA-packaging terminases, each containing a nuclease domain that resolves concatemeric DNA into genome-length units. Terminase nucleases resemble the RNase H-superfamily nucleotidyltransferases in folds, and share a two-metal-ion catalytic mechanism. Here we show that residue K428 of a bacteriophage terminase gp2 nuclease domain mediates binding of the metal cofactor Mg2+. A K428A mutation allows visualization, at high resolution, of a metal ion binding mode with a coupled-octahedral configuration at the active site, exhibiting an unusually short metal-metal distance of 2.42 A° . Such proximity of the two metal ions may play an essential role in catalysis by …
The Foot Of Homo Naledi, W. E. H. Harcourt-Smith, Z. Throckmorton, K. A. Congdon, B. Zipfel, A. S. Deane, M. S. M. Drapeau, S. E. Churchill, L. R. Berger, J. M. Desilva
The Foot Of Homo Naledi, W. E. H. Harcourt-Smith, Z. Throckmorton, K. A. Congdon, B. Zipfel, A. S. Deane, M. S. M. Drapeau, S. E. Churchill, L. R. Berger, J. M. Desilva
Publications and Research
Modern humans are characterized by a highly specialized foot that reflects our obligate bipedalism. Our understanding of hominin foot evolution is, although, hindered by a paucity of well-associated remains. Here we describe the foot of Homo naledi from Dinaledi Chamber, South Africa, using 107 pedal elements, including one nearly-complete adult foot. The H. naledi foot is predominantly modern human-like in morphology and inferred function, with an adducted hallux, an elongated tarsus, and derived ankle and calcaneocuboid joints. In combination, these features indicate a foot well adapted for striding bipedalism. However, the H. naledi foot differs from modern humans in having …