Cell Anatomy Commons^™

Enhancing Cataract Surgery Outcomes: Optimal Use Of Pre- And Post-Operative Eye Drops, Keith Skolnick M.D., Anu Valiaveedu

Mako: NSU Undergraduate Student Journal

Many preoperative and postoperative cataract patients struggle with comprehending the use of prescription medication as directed. Language barriers and low health literacy levels are major factors contributing to improper use of prescriptions. To increase patients comprehension, the Fort Lauderdale Eye Institute employed an educational intervention consisting of a live presentation and an instructional video. Results found that 44% of patients were hesitant to ask questions to clinical staff, 32% felt overwhelmed, and nearly 70% lacked confidence in using their prescribed eye drops. Following the intervention, 91% of patients reported increased confidence in their medications, and most indicated that the video …

Calculation Of Proton Transmembrane-Electrostatic Interaction Force And Elucidation Of The Water Droplet Experiment With A Transient Protonic Front, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The “transmembrane-electrostatically localized proton(s)/cation(s) charge(s) (TELC(s), also known as TELP(s)) model” may serve as a theoretical framework to explain protonic cell energetics including both delocalized and localized protonic couplings. TELCs are held by their corresponding transmembrane-electrostatically localized hydroxides anions (TELAs) across the membrane through mutual transmembrane-electrostatic attractive force, which is now calculated to be in the range from 1.96 × 10⁻¹¹ to 2.28 × 10⁻¹¹ newtons (N) across a 2.5 nm thick membrane in a range of transmembrane potential from 10 to 200 mV. At a moderate transmembrane potential (100 mV), the protonic transmembrane attractive force is now calculated to …

Deep Learning Can Be Used To Classify And Segment Plant Cell Types In Xylem Tissue, Reem Al Dabagh, Benjamin Shin, Sean Wu, Fabien Scalzo, Helen Holmlund, Jessica Lee, Chris Ghim, Samuel Fitzgerald, Marinna Grijalva

Seaver College Research And Scholarly Achievement Symposium

Studies of plant anatomical traits are essential for understanding plant physiological adaptations to stressful environments. For example, shrubs in the chaparral ecosystem of southern California have adapted various xylem anatomical traits that help them survive drought and freezing. Previous studies have shown that xylem conduits with a narrow diameter allows certain chaparral shrub species to survive temperatures as low as -12 C. Other studies have shown that increased cell wall thickness of fibers surrounding xylem vessels improves resistance to water stress-induced embolism formation. Historically, these studies on xylem anatomical traits have relied on hand measurements of cells in light micrographs, …

Telp Theory: Elucidating The Major Observations Of Rieger Et Al. 2021 In Mitochondria, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The transmembrane-electrostatically localized protons (TELP) theory may represent a complementary development to Mitchell's chemiosmotic theory. The combination of the two together can now excellently explain the energetics in mitochondria. Our calculated transmembrane-attractive force between an excess proton and an excess hydroxide explains how TELP may stay within a 1-nm thin layer at the liquid-membrane interface. Consequently, any pH sensor (sEcGFP) located at least 2–3 nm away from the membrane surface will not be able to see TELP. This feature as predicted from the TELP model was observed exactly in the experiment of Rieger et al., 2021. In contrast to their …

Therapies For Mitochondrial Disorders, Kayli Sousa Smyth, Anne Mulvihill

SURE Journal: Science Undergraduate Research Experience Journal

Mitochondria are cytoplasmic, double-membrane organelles that synthesise adenosine triphosphate (ATP). Mitochondria contain their own genome, mitochondrial DNA (mtDNA), which is maternally inherited from the oocyte. Mitochondrial proteins are encoded by either nuclear DNA (nDNA) or mtDNA, and both code for proteins forming the mitochondrial oxidative phosphorylation (OXPHOS) complexes of the respiratory chain. These complexes form a chain that allows the passage of electrons down the electron transport chain (ETC) through a proton motive force, creating ATP from adenosine diphosphate (ADP). This study aims to explore current and prospective therapies for mitochondrial disorders (MTDS). MTDS are clinical syndromes coupled with abnormalities …

Npgreat: Assembly Of The Human Subtelomere Regions With The Use Of Ultralong Nanopore Reads And Linked Reads, Eleni Adam, Desh Ranjan, Harold Riethman

Computer Science Faculty Publications

Background: Human subtelomeric DNA regulates the length and stability of adjacent telomeres that are critical for cellular function, and contains many gene/pseudogene families. Large evolutionarily recent segmental duplications and associated structural variation in human subtelomeres has made complete sequencing and assembly of these regions difficult to impossible for many loci, complicating or precluding a wide range of genetic analyses to investigate their function.

Results: We present a hybrid assembly method, NanoPore Guided REgional Assembly Tool (NPGREAT), which combines Linked-Read data with mapped ultralong nanopore reads spanning subtelomeric segmental duplications to potentially overcome these difficulties. Linked-Read sets of DNA sequences identified …

Subtype-Selective Positive Modulation Of KCa2.3 Channels Increases Cilia Length, Young-Woo Nam, Rajasekharreddy Pala, Naglaa Salem El-Sayed, Denisse Laren-Henriquez, Farideh Amirrad, Grace Yang, Mohammad Asikur Rahman, Razan Orfali, Myles Downey, Keykavous Parang, Surya M. Nauli, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca²⁺-activated potassium (K_Ca2.x) channels are gated exclusively by intracellular Ca²⁺. The activation of K_Ca2.3 channels induces hyperpolarization, which augments Ca²⁺ signaling in endothelial cells. Cilia are specialized Ca²⁺ signaling compartments. Here, we identified compound 4 that potentiates human K_Ca2.3 channels selectively. The subtype selectivity of compound 4 for human K_Ca2.3 over rat K_Ca2.2a channels relies on an isoleucine residue in the HA/HB helices. Positive modulation of K_Ca2.3 channels by compound 4 increased flow-induced Ca²⁺ signaling and cilia length, while negative …

The Effects Of Paclitaxel On Cellular Migration And The Cytoskeleton, Ashley Salguero-Gonzalez

Thinking Matters Symposium

In a clinical setting, some patients are exposed to an anti-cancer chemotherapy agent, paclitaxel. Cancerous cells undergo rapid, continuous cell division without control. Chemotherapy treatments try to slow and stop the uncontrollable cell division cycles and eliminate cancerous cells in the process. Paclitaxel serves as a treatment for some types of cancers, including lung, melanoma, bladder, and esophageal. Because it targets the cytoskeleton, paclitaxel can also influence cell migration. This project utilizes a cellular migration assay and an immunohistochemistry assay to analyze the effects of paclitaxel on the movement of cells and on the cytoskeleton of neuroglia rat cells with …

Allosteric Regulation At The Crossroads Of New Technologies: Multiscale Modeling, Networks, And Machine Learning, Gennady M. Verkhivker, Steve Agajanian, Guang Hu, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

Allosteric regulation is a common mechanism employed by complex biomolecular systems for regulation of activity and adaptability in the cellular environment, serving as an effective molecular tool for cellular communication. As an intrinsic but elusive property, allostery is a ubiquitous phenomenon where binding or disturbing of a distal site in a protein can functionally control its activity and is considered as the “second secret of life.” The fundamental biological importance and complexity of these processes require a multi-faceted platform of synergistically integrated approaches for prediction and characterization of allosteric functional states, atomistic reconstruction of allosteric regulatory mechanisms and discovery of …

Heads And Tails, Julie Simons

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Peroxiredoxin Catalysis At Atomic Resolution, Arden Perkins, Derek Parsonage, Kimberly J. Nelson, O. Maduka Ogba, Paul Ha-Yeon Cheong, Leslie B. Poole, P. Andrew Karplus

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peroxiredoxins (Prxs) are ubiquitous cysteine-based peroxidases that guard cells against oxidative damage, are virulence factors for pathogens, and are involved in eukaryotic redox regulatory pathways. We have analyzed catalytically active crystals to capture atomic resolution snapshots of a PrxQ-subfamily enzyme (from Xanthomonas campestris) proceeding through thiolate, sulfenate, and sulfinate species. These analyses provide structures of unprecedented accuracy for seeding theoretical studies, and show novel conformational intermediates giving insight into the reaction pathway. Based on a highly non-standard geometry seen for the sulfenate intermediate, we infer that the sulfenate formation itself can strongly promote local unfolding of the active site to …

An Upper Limit For Macromolecular Crowding Effects, Andrew C. Miklos, Congang Li, Courtney D. Sorell, L. Andrew Lyon, Gary J. Pielak

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background: Solutions containing high macromolecule concentrations are predicted to affect a number of protein properties compared to those properties in dilute solution. In cells, these macromolecular crowders have a large range of sizes and can occupy 30% or more of the available volume. We chose to study the stability and ps-ns internal dynamics of a globular protein whose radius is similar to 2 nm when crowded by a synthetic microgel composed of poly(N-isopropylacrylamide-co-acrylic acid) with particle radii of similar to 300 nm.

Results: Our studies revealed no change in protein rotational or ps-ns backbone dynamics and only mild …

Using A Focus Measure To Automate The Location Of Biological Tissue Surfaces In Brightfield Microscopy, Daniel Toby Elozory

USF Tampa Graduate Theses and Dissertations

The study of microstructures in brightfield microscopy using unbiased stereology plays a large and growing role in bioscience research. Stereology enables objective quantitative analysis of biological structures within a tissue sample. A first step in the stereology process is to calculate the thickness of a tissue sample by locating the top and bottom surfaces of the sample. The aim of this project is to fully automate this location process by using the relative optical focus measure as an indicator of tissue surface boundary.

The current method for identification of focus bounding planes requires a trained user to manually select the …

Simulations Of Nanopore Formation And Phosphatidylserine Externalization In Lipid Membranes Subjected To A High-Intensity, Ultrashort Electric Pulse, Q. Hu, R. P. Joshi, K. H. Schoenbach

Bioelectrics Publications

A combined MD simulator and time dependent Laplace solver are used to analyze the electrically driven phosphatidylserine externalization process in cells. Time dependent details of nanopore formation at cell membranes in response to a high-intensity (100kV∕cm), ultrashort (10ns) electric pulse are also probed. Our results show that nanosized pores could typically be formed within about 5ns. These predictions are in very good agreement with recent experimental data. It is also demonstrated that defect formation and PS externalization in membranes should begin on the anode side. Finally, the simulations confirm that PS externalization is a nanopore facilitated event, rather than the …