Digital Commons Network^™

Salt Dependence Of Thermodynamic Stability Of A Cold-Active Dna Polymerase I Fragment, Xinji Zhu

LSU Doctoral Dissertations

P. ingrahamii is a halo-psychrophilic bacterium isolated from Arctic sea ice. We have cloned and purified the large fragment of the cold-active DNA polymerase I from P. ingrahamii, named Klenpin. The objective of this project is to directly compare the thermodynamic stability of Klenpin, and the salt dependence of that stability, with Klenow and Klentaq; two homologous polymerases from a mesophile (E. coli) and a thermophile (Thermus aquaticus).

We first examined the effects of salts on the thermal stability (Tm) of Klenpin and Klenow across the Hofmeister series. Significantly different trends were observed on …

Community Context And Dispersal Stochasticity Drive Variation In Spatial Spread, Tad Dallas, Brett Melbourne, Alan Hastings

Faculty Publications

© 2020 British Ecological Society Dispersal is a key process in shaping species spatial distributions. Species interactions and variation in dispersal probabilities may jointly influence species spatial dynamics. However, many studies examine dispersal as a neutral process, independent of community context or intraspecific variation in dispersal behaviour. Here, we use controlled, replicated communities of two Tribolium species (T. castaneum and T. confusum) to examine how intraspecific variation in dispersal behaviour and community context influence dispersal dynamics in simple experimental landscapes composed of homogeneous habitat patches. We found considerable individual-level variation in dispersal probability that was unrelated to body size variation. …

Early Intracellular Trafficking And Subsequent Activity Of Programmed Cell Death In Channel Catfish Macrophages Infected With Edwardsiella Ictaluri, Lidiya P. Dubytska, Ronald L. Thune

Faculty Publications

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The development of Edwardsiella-containing-vacuoles (ECV) and the ability of Edwardsiella ictaluri to survive and replicate within macrophages suggests a unique process relative to normal phagosomal/lysosomal maturation and programed cell death. Developing ECV showed that endosomal membrane markers Rab5, EEA1, and Rab7 were all detected in both the wild type (WT) and an E. ictaluri type-3 secretion system (T3SS) mutant, 65ST. Co-localization with Lamp1, however, was significantly lower in the WT. The host cell endoplasmic reticulum marker, calnexin, co-localized to 65ST ECV significantly more than WT ECV, while Golgi vesicle marker, giantin, …

Psychological, Addictive, And Health Behavior Implications Of The Covid-19 Pandemic, Michael J. Zvolensky, Lorra Garey, Andrew H. Rogers, Norman B. Schmidt, Anka .. Vujanovic, Eric A. Storch, Julia D. Buckner, Daniel J. Paulus, Candice Alfano, Jasper A. J. Smits, Connall O'Cleirigh

Faculty Publications

No abstract provided.

Scale(S) Matter: Deconstructing An Area Of Endemism For Middle American Freshwater Fishes, Diego J. Elías, Caleb D. Mcmahan, Wilfredo A. Matamoros, Adan E. Gómez-González, Kyle R. Piller, Prosanta Chakrabarty

Faculty Publications

© 2020 John Wiley & Sons Ltd Aim: The processes that generate biodiversity occur at finer scales than are often studied, particularly in freshwater systems of the northern Neotropics. We investigate whether fine-scale biogeographic patterns are present within the larger Grijalva–Usumacinta Area of Endemism (AoE) —a region in Middle America where nearly 60% of freshwater fishes are endemic—and if present-day river basins are single historical units. Location: Northern Central America and southern Mexico. Taxon: Freshwater fishes (e.g., Cichlidae, Poeciliidae, Ostariophysi). Methods: We used fine-scale distributional data for freshwater fishes in northern Middle America (based on museum records and fieldwork) and …

Microbiological, Physicochemical, And Immunological Analysis Of A Commercial Cashew Nut-Based Yogurt, Christopher P. Mattison, Kayanush Aryana, Kristen Clermont, Eric Prestenburg, Steven W. Lloyd, Casey .. Grimm, Richard L. Wasserman

Faculty Publications

Nut-based milks and yogurts are gaining popularity, but may not offer the same benefits as dairy yogurts to consumers. Cashew nuts often cause severe allergic reactions, and cashew nut allergens are stable to several types of processing. To compare its characteristics to dairy yogurt and characterize the effects of fermentation on the Ana o 1-3 cashew nut allergens, a commercial yogurt made from cashew nuts (Cashewgurt) was evaluated for microbiological, physiochemical, and immunological properties. Average counts for lactobacilli and Streptococcus thermophilus were greater than 10 million colony forming units per milliliter, indicating the capacity to provide a health benefit. Cashewgurt …

A Novel Mutation Of The Narrow Leaf 1 Gene Adversely Affects Plant Architecture In Rice (Oryza Sativa L.), Prasanta K. Subudhi, Richard S. Garcia, Sapphire Coronejo, Teresa B. De Leon

Faculty Publications

Plant architecture is critical for enhancing the adaptability and productivity of crop plants. Mutants with an altered plant architecture allow researchers to elucidate the genetic network and the underlying mechanisms. In this study, we characterized a novel nal1 rice mutant with short height, small panicle, and narrow and thick deep green leaves that was identified from a cross between a rice cultivar and a weedy rice accession. Bulked segregant analysis coupled with genome re-sequencing and cosegregation analysis revealed that the overall mutant phenotype was caused by a 1395-bp deletion spanning over the last two exons including the transcriptional end site …

Speciation-By-Depth On Coral Reefs: Sympatric Divergence With Gene Flow Or Cryptic Transient Isolation?, Carlos Prada, Michael E. Hellberg

Faculty Publications

The distributions of many sister species in the sea overlap geographically but are partitioned along depth gradients. The genetic changes leading to depth segregation may evolve in geographic isolation as a prerequisite to coexistence or may emerge during primary divergence leading to new species. These alternatives can now be distinguished via the power endowed by the thousands of scorable loci provided by second-generation sequence data. Here, we revisit the case of two depth-segregated, genetically isolated ecotypes of the nominal Caribbean candelabrum coral Eunicea flexuosa. Previous analyses based on a handful of markers could not distinguish between models of genetic exchange …

Energy Expenditure And Macronutrient Oxidation In Response To An Individualized Nonshivering Cooling Protocol, Guillermo Sanchez-Delgado, Juan M.A. Alcantara, Francisco M. Acosta, Borja Martinez-Tellez, Francisco J. Amaro-Gahete, Elisa Merchan-Ramirez, Marie Löf, Idoia Labayen, Eric Ravussin, Jonatan R. Ruiz

Clinical Research Faculty Publications

Objective: This study aimed to describe the energy expenditure (EE) and macronutrient oxidation response to an individualized nonshivering cold exposure in young healthy adults. Methods: Two different groups of 44 (study 1: 22.1 [SD 2.1] years old, 25.6 [SD 5.2] kg/m2, 34% men) and 13 young healthy adults (study 2: 25.6 [SD 3.0] years old, 23.6 [SD 2.4] kg/m2, 54% men) participated in this study. Resting metabolic rate (RMR) and macronutrient oxidation rates were measured by indirect calorimetry under fasting conditions in a warm environment (for 30 minutes) and in mild cold conditions (for 65 minutes, with the individual wearing …

Mutations In The Pectin Methyltransferase Quasimodo2 Influence Cellulose Biosynthesis And Wall Integrity In Arabidopsis, Juan Du, Alex Kirui, Shixin Huang, Lianglei Wang, William J. Barnes, Sarah N. Kiemle, Yunzhen Zheng, Yue Rui, Mei Ruan, Shiqian Qi, Seong H. Kim, Tuo Wang, Daniel J. Cosgrove, Charles T. Anderson, Chaowen Xiao

Faculty Publications

© 2020 ASPB. Pectins are abundant in the cell walls of dicotyledonous plants, but how they interact with other wall polymers and influence wall integrity and cell growth has remained mysterious. Here, we verified that QUASIMODO2 (QUA2) is a pectin methyltransferase and determined that QUA2 is required for normal pectin biosynthesis. To gain further insight into how pectin affects wall assembly and integrity maintenance, we investigated cellulose biosynthesis, cellulose organization, cortical microtubules, and wall integrity signaling in two mutant alleles of Arabidopsis (Arabidopsis thaliana) QUA2, qua2 and tsd2. In both mutants, crystalline cellulose content is reduced, cellulose synthase particles move …

A Coded Aperture Microscope For X-Ray Fluorescence Full-Field Imaging, D. P. Siddons, A. J. Kuczewski, A. K. Rumaiz, R. Tappero, M Idir, K. Nakhoda, J. Khanfri, V. Singh, E. R. Farquhar, M. Sullivan, D. Abel, D. J. Brady, X. Yuan

Faculty Publications

The design and construction of an instrument for full-field imaging of the X-ray fluorescence emitted by a fully illuminated sample are presented. The aim is to produce an X-ray microscope with a few micrometers spatial resolution, which does not need to scan the sample. Since the fluorescence from a spatially inhomogeneous sample may contain many fluorescence lines, the optic which will provide the magnification of the emissions must be achromatic, i.e. its optical properties must be energy-independent. The only optics which fulfill this requirement in the X-ray regime are mirrors and pinholes. The throughput of a simple pinhole is very …

Single-Case Experimental Designs For Behavioral Neuroscience, Paul L. Soto

Faculty Publications

Single-case experimental designs (SCEDs) are commonly used in behavior analytic research but rarely used in behavioral neuroscience research. The recent development of technologies that allow control of the timing of neurobiological events such as gene expression and neuronal firing enable the fruitful application of SCEDs for the study of brain-behavior relations. There are at least 3 benefits expected from applying SCEDs to study how neurobiological events affect behavior. First, SCEDs entail direct within- and across-subject assessments of reliability, likely increasing the probability of replication across studies and encouraging a search for the causes of replication failure when they occur. Second, …

Utilization Of Deep Learning For Subphenotype Identification In Sepsis-Associated Acute Kidney Injury, Kumardeep Chaudhary, Akhil Vaid, Áine Duffy, Ishan Paranjpe, Suraj Jaladanki, Manish Paranjpe, Kipp Johnson, Avantee Gokhale, Pattharawin Pattharanitima, Kinsuk Chauhan, Ross O’Hagan, Tielman Van Vleck, Steven G. Coca, Richard Cooper, Benjamin Glicksberg, Erwin P. Bottinger, Lili Chan, Girish N. Nadkarni

Faculty Publications

Background and objectives Sepsis-associated AKI is a heterogeneous clinical entity. We aimed to agnostically identify sepsis-associated AKI subphenotypes using deep learning on routinely collected data in electronic health records. Design, setting, participants, & measurements We used the Medical Information Mart for Intensive Care III database, which consists of electronic health record data from intensive care units in a tertiary care hospital in the United States. We included patients ≥18 years with sepsis who developed AKI within 48 hours of intensive care unit admission. We then used deep learning to utilize all available vital signs, laboratory measurements, and comorbidities to identify …

Effects Of Cold Storage On Life-History Traits Of Aphidius Matricariae, Mehran Rezaei, Ali A. Talebi, Yaghoub Fathipour, Javad Karimzadeh, Mohammad Mehrabadi, Gadi V.P. Reddy

Faculty Publications

Aphidius matricariae Haliday (Hymenoptera: Braconidae) is a polyphagous solitary endoparasitoid, attacking more than 40 species of aphids. This parasitoid is an important commercial product of many companies that produce biological control agents. Storage at low temperature increases the shelf life of many biocontrol agents, allowing companies to provide a steady and sufficient supply of insects for biocontrol programs. In the current study, the effects of cold storage of 1-day-old host mummies with A. matricariae for various time periods (5, 10, 15, 20, and 30 days) at 5 °C on the parasitoid’s key life-history traits were investigated. Parameters assessed after storage …

Potential Link Between Compromised Air Quality And Transmission Of The Novel Corona Virus (Sars-Cov-2) In Affected Areas, M. G. Manoj, M. K. Satheesh Kumar, K. T. Valsaraj, C. Sivan, Soumya K. Vijayan

Faculty Publications

The emergence of a novel human corona virus disease (COVID-19) has been declared as a pandemic by the World Health Organization. One of the mechanisms of airborne transmission of the severe acute respiratory syndrome corona virus (SARS-CoV-2) amid humans is through direct ejection of droplets via sneezing, coughing and vocalizing. Nevertheless, there are ample evidences of the persistence of infectious viruses on inanimate surfaces for several hours to a few days. Through a critical review of the current literature and a preliminary analysis of the link between SARS-CoV-2 transmission and air pollution in the affected regions, we offer a perspective …

A Novel Approach To Assess Metabolic Flexibility Overnight In A Whole-Body Room Calorimeter, David H. Mcdougal, Kara L. Marlatt, Robbie A. Beyl, Leanne M. Redman, Eric Ravussin

Division of Basic Science Faculty Publications

Objective: This study aimed to investigate a novel approach for determining the effects of energy-standardized dinner meals (high-fat and low-fat) on respiratory exchange ratio (RER) dynamics and metabolic flexibility. Methods: Using a randomized crossover study design, energy expenditure, RER, and macronutrient oxidation rates were assessed in response to a single dinner meal during an overnight stay in a whole-body room calorimeter. Eight healthy adults completed two overnight chamber stays while fed either a high-fat (60% fat, 20% carbohydrate [CHO], 20% protein; food quotient [FQ] = 0.784) or low-fat (20% fat, 60% CHO, 20% protein; FQ = 0.899) dinner containing 40% …

Novel Targets In Glucose Homeostasis And Obesity—Lesson From Rare Mutations, Bing Feng, Pingwen Xu, Yanlin He

Division of Basic Science Faculty Publications

Purpose of Review: Obesity and diabetes have already become the second largest risk factor for cardiovascular disease. During the last decade, remarkable advances have been made in understanding the human genome’s contribution to glucose homeostasis disorders and obesity. A few studies on rare mutations of candidate genes provide potential genetic targets for the treatment of diabetes and obesity. In this review, we discussed the detailed findings of these studies and the possible causalities between specific genetic variations and dysfunctions in energy or glucose homeostasis. We are optimistic that novel therapeutic strategies targeting these specific mutants for treating and preventing diabetes …

Indirect, Non-Thermal Atmospheric Plasma Promotes Bacterial Killing In Vitro And Wound Disinfection In Vivo Using Monogenic And Polygenic Models Of Type 2 Diabetes (Without Adverse Metabolic Complications), Chris R. Cooley, John Mark Mclain, Samuel D. Dupuy, Adrianna E. Eder, Molly Wintenberg, Kimberly Kelly-Wintenberg, Alan Wintenberg, J. Jason Collier, Susan J. Burke, Michael D. Karlstad

Division of Basic Science Faculty Publications

ABSTRACTA novel atmospheric plasma device that uses indirect, non-thermal plasma generated from room air is being studied for its effects on wound disinfection in animal wounds of monogenic and polygenic murine models of type 2 diabetes. As a proof-of-concept report, the goal of this study was to demonstrate the efficacy and safety of the indirect non-thermal plasma (INTP) device in disinfecting polycarbonate filters established with Pseudomonas aeruginosa (PAO1) biofilms as well as wound disinfection in diabetic murine wounds. Dorsal excisional wounds in BALB/c, polygenic TALLYHO, and monogenic db/db mice established with PAO1 infection all demonstrated a 3-log colony-forming unit (CFU) …

Metabolic Health Status Contributes To Transcriptome Alternation In Human Visceral Adipose Tissue During Obesity, Qiuzhong Zhou, Zhenzhen Fu, Yingyun Gong, Veerabrahma Pratap Seshachalam, Jia Li, Yizhe Ma, Hui Liang, Wei Guan, Shibo Lin, Sujoy Ghosh, Lei Sun, Hongwen Zhou

Division of Basic Science Faculty Publications

Objective: BMI is a well-established factor affecting the transcriptome profile of adipose tissue, but there are few reports on the relationship between the metabolic health status of people with obesity and the transcriptional changes, particularly in visceral adipose tissue. Methods: Visceral adipose tissue was collected from three subgroups of patients, lean (n = 11), metabolically healthy obesity (MHO; n = 22), and metabolically unhealthy obesity (MUO; n = 26), and RNA sequencing was conducted to profile the transcriptome changes between these groups in a pairwise manner. Results: Comparing MUO with lean and comparing MHO with lean revealed similar patterns in …

The Effects Of Family Transitions On Depressive Symptoms: Differences Among Young Adults With And Without Childhood Symptoms Of Attention-Deficit/Hyperactivity Disorder, Rhiannon A. Kroeger, Debra Umberson, Daniel A. Powers, Danequa L. Forrest

Faculty Publications

Attention-deficit/hyperactivity disorder (ADHD) is tied to higher levels of depression, but the social factors that shape these associations are not well understood. This study considers whether family transitions affect depressive symptoms differently for young adults with and without childhood symptoms of ADHD at subthreshold or diagnostic levels. Between-within regression analysis of nationally representative longitudinal survey data shows that transitions into cohabitation and parenthood affect depressive symptoms differently for young adults with and without childhood symptoms of ADHD. Specifically, within-person effects indicate that transitions into cohabitation and parenthood are tied to decreases in depressive symptoms, but only for young adults without …

Trade-Offs Tip Toward Litter Trapping: Insights From A Little-Known Panamanian Cloud-Forest Treelet, Kyle E. Harms, James W. Dalling, María N. Sánchez De Stapf

Faculty Publications

No abstract provided.

Exploring The Role Of Ccp1 And Ccp2 In The Chlamydomonas Reinhardtii Carbon Dioxide Concentrating Mechanism, Lillian Laplace

Honors Capstones

No abstract provided.

Ribosomal Rna Synthesis After Induced Nucleolar Stress In Drosophila Melanogaster, Kyle Maher

Honors Capstones

No abstract provided.

Increasing The Bioavailability Of Poorly Soluble Anti-Cancer Prodrugs Through Encapsulation In Platinum Based Nanocages, Salim Cesar Lutfallah

Honors Capstones

No abstract provided.

Characterizing Drosophila Melanogaster Sleep Models Using An Optogenetic Engineered Caspase And Channelrhodopsins, Corey Cooper

Honors Capstones

No abstract provided.

A Numerical Investigation Of Salinity Variations In The Barataria Estuary, Louisiana In Connection With The Mississippi River And Restoration Activities, Yanda Ou, Z. George Xue, Chunyan Li, Kehui Xu, John R. White, Samuel J. Bentley, Zhengchen Zang

Faculty Publications

© 2020 Elsevier Ltd A three-dimensional numerical model was applied to the Barataria Estuary in the Northern Gulf of Mexico to study its salinity variations as well as the impacts from the Mississippi River discharges and proposed river diversions. Model-observation comparison showed that the model was able to reproduce the hydrodynamic fields on subtidal to seasonal time scales. Salinity in the Barataria Estuary was high in fall and low in summer, with a greater variability in the lower estuary than the upper estuary. While salinity in the upper estuary was controlled by discharges from a local freshwater diversion, salinity in …

Characterizing The Biophysical Properties And Origin Of Extracellular Matrix In The Breast Tumor Microenvironment, Connor T. King

LSU Master's Theses

Tumors derived from breast tissue possess the ability to manipulate and permanently alter their surrounding tissue. Studies demonstrate that tissues surrounding breast tumors have differences in secreted factors as well as extracellular matrix (ECM) deposition and structure. However, some fundamental gaps exist within this paradigm: specifically, what exacerbates this transformation and are these changes maintained between the subtypes of breast tumors? Therefore, a targeted evaluation of the effects of the tumor on the stromal microenvironment in a subtype specific manner will be invaluable. To determine if tumor aggressiveness and subtype differentially regulate the tumor microenvironment, a model must be constructed …

From Regulation Of Secondary Metabolites To Increased Virulence Under Sublethal Dosage Of Antibiotics: An Unprecedented Role Of Global Regulator, Mftr, In Burkholderia Thailandensis, Sudarshan Singh Thapa

LSU Doctoral Dissertations

The rise of multi-drug resistant bacteria combined with a decreasing pool of effective antibiotics has placed an increasing need for the development of novel antibiotics. Bacterial natural products or secondary metabolites have been the greatest source for development of novel antibiotics. The genus Burkholderia has recently emerged as a source of promising compounds with antibacterial, antifungal, and anti-cancer activities. Bacterial secondary metabolites provide added advantage to bacteria under stressful environments such as during host infection, evading predators or nutrient deficient conditions. However, genes involved in synthesis of these novel compounds remain silent under normal laboratory growth, creating a hurdle in …

A Vaccine Targeting The Rbd Of The S Protein Of Sars-Cov-2 Induces Protective Immunity, Jingyun Yang, Wei Wang, Zimin Chen, Shuaiyao Lu, Fanli Yang, Zhenfei Bi, Linlin Bao, Fei Mo, Xue Li, Yong Huang, Weiqi Hong, Yun Yang, Yuan Zhao, Fei Ye, Sheng Lin, Wei Deng, Hua Chen, Hong Lei, Ziqi Zhang, Min Luo, Hong Gao, Yue Zheng, Yanqiu Gong, Xiaohua Jiang, Yanfeng Xu, Qi Lv, Dan Li, Manni Wang, Fengdi Li, Shunyi Wang, Guanpeng Wang, Pin Yu, Yajin Qu, Li Yang

Division of Basic Science Faculty Publications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a respiratory disease called coronavirus disease 2019 (COVID-19), the spread of which has led to a pandemic. An effective preventive vaccine against this virus is urgently needed. As an essential step during infection, SARS-CoV-2 uses the receptor-binding domain (RBD) of the spike protein to engage with the receptor angiotensin-converting enzyme 2 (ACE2) on host cells1,2. Here we show that a recombinant vaccine that comprises residues 319–545 of the RBD of the spike protein induces a potent functional antibody response in immunized mice, rabbits and non-human primates (Macaca mulatta) as early as 7 …

The Role Of Sediment-Induced Light Attenuation On Primary Production During Hurricane Gustav (2008), Zhengchen Zang, Z. George Xue, Kehui Xu, Samuel J. Bentley, Qin Chen, Eurico J. D'Sa, Le Zhang, Yanda Ou

Faculty Publications

We introduced a sediment-induced light attenuation algorithm into a biogeochemical model of the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system. A fully coupled ocean-atmospheric-sediment-biogeochemical simulation was carried out to assess the impact of sediment-induced light attenuation on primary production in the northern Gulf of Mexico during the passage of Hurricane Gustav in 2008. When compared with model results without sediment-induced light attenuation, our new model showed a better agreement with satellite data on both the magnitude of nearshore chlorophyll concentration and the spatial distribution of offshore bloom. When Hurricane Gustav approached, resuspended sediment shifted the inner shelf ecosystem from a nutrient-limited …