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Amino Acids, Peptides, and Proteins

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Articles 1 - 25 of 25

Full-Text Articles in Chemical Actions and Uses

Silvestrol Inhibits Nasopharyngeal Carcinoma Cells And Synergizes With Cx‑5461: Insights From A Proteomics Study, Maelinda Daker, Munirah Ahmad, Alan Khoo, Lu Ping Tan, Siok-Fong Chin, Siaw San Hwang, Paul Neilsen Aug 2025

Silvestrol Inhibits Nasopharyngeal Carcinoma Cells And Synergizes With Cx‑5461: Insights From A Proteomics Study, Maelinda Daker, Munirah Ahmad, Alan Khoo, Lu Ping Tan, Siok-Fong Chin, Siaw San Hwang, Paul Neilsen

Department of Medical Oncology Faculty Papers

Nasopharyngeal carcinoma (NPC) is a cancer arising from the epithelial cells of the nasopharynx, which is rare in Western countries but extremely prevalent in Borneo and the Southern China region. Present-day hurdles in NPC treatment that lead to poor quality of life and poor survival include distant metastasis and resistance to chemoradiotherapy. Silvestrol and its 5'''-epimer, episilvestrol, are compounds isolated from the plant Aglaia stellatopilosa, which is endemic to Borneo. Silvestrol, a protein synthesis inhibitor, preferentially inhibits the translation of cancer-associated mRNAs. CX-5461 is an inhibitor of RNA polymerase I that catalyzes rRNA synthesis. The present study sought to …


Ovarian Cancer G Protein-Coupled Receptor-1 Signaling Bias Dictates Anti-Contractile Effect Of Benzodiazepines On Airway Smooth Muscle, Dominic R. Villalba, Arun K. Jannu, Elham Javed, Isha Dandekar, Ruping Wang, Deepak A. Deshpande, Steven S. An, Reynold A. Panettieri, Dale D. Tang, Raymond B. Penn, Ajay P. Nayak May 2025

Ovarian Cancer G Protein-Coupled Receptor-1 Signaling Bias Dictates Anti-Contractile Effect Of Benzodiazepines On Airway Smooth Muscle, Dominic R. Villalba, Arun K. Jannu, Elham Javed, Isha Dandekar, Ruping Wang, Deepak A. Deshpande, Steven S. An, Reynold A. Panettieri, Dale D. Tang, Raymond B. Penn, Ajay P. Nayak

Center for Translational Medicine Faculty Papers

BACKGROUND: We recently reported that the ovarian cancer G protein-coupled receptor-1 (OGR1) can be pharmacologically biased with specific benzodiazepines to couple with distinct heterotrimeric G proteins in human airway smooth muscle (ASM) cells. Lorazepam stimulated both G

METHODS: Models of histamine (His) -stimulated contraction included imaging of ex vivo human precision cut lung slices (hPCLS) and Magnetic Twisting Cytometry (MTC) analysis of human ASM cell stiffness. To explore mechanisms of regulation, we examined effects on myosin light chain (pMLC) phosphorylation and PKA activity in primary human ASM cultures, as well as actin cytoskeleton integrity as defined by changes in the …


Mouse Adrenal Macrophages Are Associated With Pre- And Postsynaptic Neuronal Elements And Respond To Multiple Neuromodulators, Matthew D. Whim Feb 2025

Mouse Adrenal Macrophages Are Associated With Pre- And Postsynaptic Neuronal Elements And Respond To Multiple Neuromodulators, Matthew D. Whim

School of Medicine Faculty Publications

The adrenal medulla is packed with chromaffin cells, modified postganglionic sympathetic neurons that secrete the catecholamines, epinephrine and norepinephrine, during the fight-or-flight response. Sometimes overlooked is a population of immune cells that also resides within the gland but whose distribution and function are not clear. Here I examine the location of CD45+ hematopoietic cells in the mouse adrenal medulla and show the majority are F4/80+/Lyz2+ macrophages. These cells are present from early postnatal development and widely distributed. Anatomically they are associated with chromaffin cells, found aligned alongside synapsin-IR neuronal varicosities and juxtaposed to CD31-IR blood vessels. Using Lyz2cre-GCaMP6f mice to …


Beyond Checkpoint Inhibitors: The Three Generations Of Immunotherapy, John Schaub, Shou-Ching Tang Jan 2025

Beyond Checkpoint Inhibitors: The Three Generations Of Immunotherapy, John Schaub, Shou-Ching Tang

School of Medicine Faculty Publications

Anti-tumor immunotherapy was rediscovered and rejuvenated in the last two decades with the discovery of CTLA-4, PD-1 and PD-L1 and the roles in inhibiting immune function and tumor evasion of anti-tumor immune response. Following the approval of the first checkpoint inhibitor ipilimumab against CTLA-4 in melanoma in 2011, there has been a rapid development of tumor immunotherapy. Furthermore, additional positive and negative molecules among the T-cell regulatory systems have been identified that that function to fine tune the stimulatory or inhibitory immune cells and modulate their functions (checkpoint modulators). Many strategies are being explored to target macrophages, NK-cells, cytotoxic T-cells, …


Tryptophan Kynurenine Pathway-Based Imaging Agents For Brain Disorders And Oncology-From Bench To Bedside, Erik Stauff, Wenqi Xu, Heidi H. Kecskemethy, Sigrid A. Langhans, Vinay V. R. Kandula, Lauren W. Averill, Xuyi Yue Jan 2025

Tryptophan Kynurenine Pathway-Based Imaging Agents For Brain Disorders And Oncology-From Bench To Bedside, Erik Stauff, Wenqi Xu, Heidi H. Kecskemethy, Sigrid A. Langhans, Vinay V. R. Kandula, Lauren W. Averill, Xuyi Yue

Jefferson Hospital Staff Papers and Presentations

Tryptophan (Trp)-based radiotracers have excellent potential for imaging many different types of brain pathology because of their involvement with both the serotonergic and kynurenine (KYN) pathways. However, radiotracers specific to the kynurenine metabolism pathway are limited. In addition, historically Trp-based radiopharmaceuticals were synthesized with the short-lived isotope carbon-11. A newer generation of Trp-based imaging agents using the longer half-lived and commercially available isotopes, such as fluorine-18 and iodine-124, are being developed. The newly developed amino acid-based tracers have been demonstrated to have favorable radiochemical and imaging characteristics in pre-clinical studies. However, many barriers still exist in the clinical translation of …


Treatment Sequence With Tebentafusp And Immune Checkpoint Inhibitors In Patients With Metastatic Uveal Melanoma And Metastatic Gna11/Gnaq Mutant Melanocytic Tumors, Florentia Dimitriou, Marlana Orloff, Erica Koch Hein, Phil Cheng, Isaac Hughes, Ester Simeone, Kamaneh Montazeri, Piyush Grover, Inderjit Mehmi, Camille Gerard, Caroline Gaudy-Marqueste, Jean-Jacques Grob, Olivier Michielin, Omid Hamid, Georgina Long, Ryan Sullivan, Ellen Kapiteijn, Douglas Johnson, Paolo Ascierto, Anthony Joshua, Richard Carvajal, Marcus Butler, Jessica Hassel, Reinhard Dummer Jan 2025

Treatment Sequence With Tebentafusp And Immune Checkpoint Inhibitors In Patients With Metastatic Uveal Melanoma And Metastatic Gna11/Gnaq Mutant Melanocytic Tumors, Florentia Dimitriou, Marlana Orloff, Erica Koch Hein, Phil Cheng, Isaac Hughes, Ester Simeone, Kamaneh Montazeri, Piyush Grover, Inderjit Mehmi, Camille Gerard, Caroline Gaudy-Marqueste, Jean-Jacques Grob, Olivier Michielin, Omid Hamid, Georgina Long, Ryan Sullivan, Ellen Kapiteijn, Douglas Johnson, Paolo Ascierto, Anthony Joshua, Richard Carvajal, Marcus Butler, Jessica Hassel, Reinhard Dummer

Kimmel Cancer Center Faculty Papers

BACKGROUND: Metastatic uveal melanoma (mUM) is rare. Immune checkpoint inhibitors (ICIs) have shown modest efficacy in mUM. Tebentafusp prolonged overall survival (OS) in a phase 3 study. We aimed to investigate the efficacy and safety of the sequence of tebentafusp and ICIs.

METHODS: Patients with HLA-A * 02:01 positive mUM, or metastatic GNA11/GNAQ mutant melanocytic tumors treated with tebentafusp followed by ICIs (group 1) or the inverse sequence (group 2) at any treatment line were retrospectively identified. The primary objective was OS rate at 2 years.

RESULTS: 131 patients were included; 51 in group 1 and 80 in group 2. …


The Complexity And Significance Of Fibroblast Growth Factor (Fgf) Signaling For Fgf-Targeted Cancer Therapies, Anh Nguyen, Caroline Facey, Bruce Boman Dec 2024

The Complexity And Significance Of Fibroblast Growth Factor (Fgf) Signaling For Fgf-Targeted Cancer Therapies, Anh Nguyen, Caroline Facey, Bruce Boman

Department of Pharmacology and Experimental Therapeutics Faculty Papers

Fibroblast growth factors (FGFs) have diverse functions in the regulation of cell proliferation and differentiation in development, tissue maintenance, wound repair, and angiogenesis. The goal of this review paper is to (i) deliberate on the role of FGFs and FGF receptors (FGFRs) in different cancers, (ii) present advances in FGF-targeted cancer therapies, and (iii) explore cell signaling mechanisms that explain how FGF expression becomes dysregulated during cancer development. FGF is often mutated and overexpressed in cancer and the different FGF and FGFR isoforms have unique expression patterns and distinct roles in different cancers. Among the FGF members, the FGF 15/19 …


Poptosis Or Peptide-Induced Transmembrane Pore Formation: A Novel Way To Kill Cancer Cells Without Affecting Normal Cells, Matthew Pincus, Miriam Silberstein, Nitzan Zohar, Ehsan Sarafraz-Yazdi, Wilbur Bowne May 2024

Poptosis Or Peptide-Induced Transmembrane Pore Formation: A Novel Way To Kill Cancer Cells Without Affecting Normal Cells, Matthew Pincus, Miriam Silberstein, Nitzan Zohar, Ehsan Sarafraz-Yazdi, Wilbur Bowne

Department of Surgery Faculty Papers

Recent advances in cancer treatment like personalized chemotherapy and immunotherapy are aimed at tumors that meet certain specifications. In this review, we describe a new approach to general cancer treatment, termed peptide-induced poptosis, in which specific peptides, e.g., PNC-27 and its shorter analogue, PNC-28, that contain the segment of the p53 transactivating 12-26 domain that bind to HDM-2 in its 1-109 domain, bind to HDM-2 in the membranes of cancer cells, resulting in transmembrane pore formation and the rapid extrusion of cancer cell contents, i.e., tumor cell necrosis. These peptides cause tumor cell necrosis of a wide variety of solid …


Host-Defense Piscidin Peptides As Antibiotic Adjuvants Against Clostridioides Difficile, Adenrele Oludiran, Areej Malik, Andriana C. Zourou, Yonghan Wu, Steven P. Gross, Albert Siryapon, Asia Poudel, Kwincy Alleyne, Savion Adams, David S. Courson, Myriam L. Cotten, Erin B. Purcell Jan 2024

Host-Defense Piscidin Peptides As Antibiotic Adjuvants Against Clostridioides Difficile, Adenrele Oludiran, Areej Malik, Andriana C. Zourou, Yonghan Wu, Steven P. Gross, Albert Siryapon, Asia Poudel, Kwincy Alleyne, Savion Adams, David S. Courson, Myriam L. Cotten, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The spore-forming intestinal pathogen Clostridioides difficile causes multidrug resistant infection with a high rate of recurrence after treatment. Piscidins 1 (p1) and 3 (p3), cationic host defense peptides with micromolar cytotoxicity against C. difficile, sensitize C. difficile to clinically relevant antibiotics tested at sublethal concentrations. Both peptides bind to Cu2+ using an amino terminal copper and nickel binding motif. Here, we investigate the two peptides in the apo and holo states as antibiotic adjuvants against an epidemic strain of C. difficile. We find that the presence of the peptides leads to lower doses of …


The Kinetic Modulation Of Α - Synuclein Fibrillation And Toxicity By 4-Phenylbutyric Acid, Kristos Awuah Baffour Jan 2024

The Kinetic Modulation Of Α - Synuclein Fibrillation And Toxicity By 4-Phenylbutyric Acid, Kristos Awuah Baffour

Graduate Theses/Dissertations

ABSTRACT

The Protein misfolding and aggregation of alpha-synuclein (α-syn) into neurotoxic amyloids underlies the pathogenesis of neurodegenerative diseases such as Parkinson's disease (PD). 4-Phenylbutyrate (PBA), an FDA drug approved for treating urea cycle disorders, has garnered significant attention as a potential chemical chaperone for targeting alpha-synuclein (α-syn) aggregation. Using in vitro assays, we demonstrated that PBA treatment alters the pattern of α-syn aggregation, as evidenced by reduced formation of oligomeric species and its increased susceptibility to proteolytic cleavage under the influence of PBA. Proteinase K assay, surface plasmon resonance, and Nile red studies indicate that PBA interacts with the extensive …


Targeting Mcl-1 By A Small Molecule Nsc260594 For Triple-Negative Breast Cancer Therapy, Shengli Dong, Margarite D. Matossian, Hassan Yousefi, Maninder Khosla, Bridgette M. Collins-Burow, Matthew E. Burow, Suresh K. Alahari Jul 2023

Targeting Mcl-1 By A Small Molecule Nsc260594 For Triple-Negative Breast Cancer Therapy, Shengli Dong, Margarite D. Matossian, Hassan Yousefi, Maninder Khosla, Bridgette M. Collins-Burow, Matthew E. Burow, Suresh K. Alahari

School of Graduate Studies Faculty Publications

Triple-negative breast cancers (TNBCs) are aggressive forms of breast cancer and tend to grow and spread more quickly than most other types of breast cancer. TNBCs can neither be targeted by hormonal therapies nor the antibody trastuzumab that targets the HER2 protein. There are urgent unmet medical needs to develop targeted drugs for TNBCs. We identified a small molecule NSC260594 from the NCI diversity set IV compound library. NSC260594 exhibited dramatic cytotoxicity in multiple TNBCs in a dose-and time-dependent manner. NSC260594 inhibited the Myeloid cell leukemia-1 (Mcl-1) expression through downregulation of Wnt signaling proteins. Consistent with this, NSC260594 treatment increased …


High Glucose-Upregulated Pd-L1 Expression Through Ras Signaling-Driven Downregulation Of Ptrh1 Leads To Suppression Of T Cell Cytotoxic Function In Tumor Environment, Chenggang Gao, Jiaoshun Chen, Jianwei Bai, Haoxiang Zhang, Yanyi Tao, Shihong Wu, Hehe Li, Heshui Wu, Qiang Shen, Tao Yin Jul 2023

High Glucose-Upregulated Pd-L1 Expression Through Ras Signaling-Driven Downregulation Of Ptrh1 Leads To Suppression Of T Cell Cytotoxic Function In Tumor Environment, Chenggang Gao, Jiaoshun Chen, Jianwei Bai, Haoxiang Zhang, Yanyi Tao, Shihong Wu, Hehe Li, Heshui Wu, Qiang Shen, Tao Yin

School of Graduate Studies Faculty Publications

Background: Nearly 80% of patients with pancreatic cancer suffer from glucose intolerance or diabetes. Pancreatic cancer complicated by diabetes has a more immunosuppressive tumor microenvironment (TME) and is associated with a worse prognosis. The relationship between glucose metabolism and programmed cell death-Ligand 1 (PD-L1) is close and complex. It is important to explore the regulation of high glucose on PD-L1 expression in pancreatic cancer and its effect on infiltrating immune effectors in the tumor microenvironment. Methods: Diabetic murine models (C57BL/6) were used to reveal different immune landscape in euglycemic and hyperglycemic pancreatic tumor microenvironment. Bioinformatics, WB, iRIP [Improved RNA Binding …


Enhancement Of Tki Sensitivity In Lung Adenocarcinoma Through M6a-Dependent Translational Repression Of Wnt Signaling By Circ-Fbxw7, Kai Li, Zi Yang Peng, Rui Wang, Xiang Li, Ning Du, Da Peng Liu, Jia Zhang, Yun Feng Zhang, Lei Ma, Ye Sun, Shou Ching Tang, Hong Ren, Yi Ping Yang, Xin Sun Jul 2023

Enhancement Of Tki Sensitivity In Lung Adenocarcinoma Through M6a-Dependent Translational Repression Of Wnt Signaling By Circ-Fbxw7, Kai Li, Zi Yang Peng, Rui Wang, Xiang Li, Ning Du, Da Peng Liu, Jia Zhang, Yun Feng Zhang, Lei Ma, Ye Sun, Shou Ching Tang, Hong Ren, Yi Ping Yang, Xin Sun

School of Medicine Faculty Publications

Background: Tyrosine kinase inhibitors (TKIs) that specifically target mutational points in the EGFR gene have significantly reduced suffering and provided greater relief to patients with lung adenocarcinoma (LUAD). The third-generation EGFR-TKI, Osimertinib, has been successfully employed in clinical treatments to overcome resistance to both original and acquired T790M and L858R mutational points. Nevertheless, the issue of treatment failure response has emerged as an insurmountable problem. Methods: By employing a combination of multiple and integrated approaches, we successfully identified a distinct population within the tumor group that plays a significant role in carcinogenesis, resistance, and recurrence. Our research suggests that addressing …


The Developing Effects Of Potassium Ferricyanide On Tetrahymena, Katelyn Coronell May 2023

The Developing Effects Of Potassium Ferricyanide On Tetrahymena, Katelyn Coronell

Whittier Scholars Program

Potassium Cyanide is a highly toxic chemical asphyxiant that interferes with the body's ability to use oxygen, typically by directly affecting the body by ingestion, inhalation, skin contact, or eye contact(CDC, 2011). Due to its high toxicity, the main effect that leads to the downfall of the organism begins with the cessation of aerobic metabolism; it does this by cyanide binding to the ferric ions and inhibiting cytochrome oxidase within the mitochondria (Zhang, 2015). There are no physical dangers the substance causes. Although, there are many chemical dangers. If used at temperatures higher than 70℉ The substance may produce toxic …


Induction Of Antimicrobial Protein S100a15 Expression By Oral Microbial Pathogens Is Toll-Like Receptors-Dependent Activation Of C-Jun-N-Terminal Kinase (Jnk), P38, And Nf-Κb Pathways, Denis Selimovic, Naji Kharouf, Florence Carrouel, Sofie Yasmin Hassan, Thomas W. Flanagan, Sarah Lilly Hassan, Mosaad Megahed, Youssef Haikel, Simeon Santourlidis, Mohamed Hassan Mar 2023

Induction Of Antimicrobial Protein S100a15 Expression By Oral Microbial Pathogens Is Toll-Like Receptors-Dependent Activation Of C-Jun-N-Terminal Kinase (Jnk), P38, And Nf-Κb Pathways, Denis Selimovic, Naji Kharouf, Florence Carrouel, Sofie Yasmin Hassan, Thomas W. Flanagan, Sarah Lilly Hassan, Mosaad Megahed, Youssef Haikel, Simeon Santourlidis, Mohamed Hassan

School of Medicine Faculty Publications

The antimicrobial protein S100A15 belongs to the S100 family, which is differentially expressed in a variety of normal and pathological tissues. Although the function of S100A15 protein has been discussed in several studies, its induction and regulation in oral mucosa, so far, are largely unknown. In this study, we demonstrate that S100A15 is induced by the stimulation of oral mucosa with gram− or gram+ bacterial pathogens, as well as with the purified membrane components, namely lipopolysaccharides (LPS) and lipoteichoic acid (LTA). The stimulation of the human gingival fibroblast (GF) and the human mouth epidermal carcinoma (KB) cell lines with either …


Alternative Fixation Of Venous Valves For Bioprosthetic Applications, Makenzie Kapales May 2022

Alternative Fixation Of Venous Valves For Bioprosthetic Applications, Makenzie Kapales

Biomedical Engineering Undergraduate Honors Theses

Venous valve failure allows for the retrograde, or backward, flow of blood into the lower extremities, which leads to Chronic Venous Insufficiency (CVI). CVI infringes upon quality of life through ulceration and can result in death due to Deep Vein Thrombosis (DVT), or blood clots, causing pulmonary embolism. A successful treatment of CVI restores valve function and prevents retrograde blood flow; however, current bioprosthetic venous valves exhibit low patency and high calcification. To improve upon bioprosthetic venous valves and CVI treatment, the University of Arkansas’s Cardiovascular Biomechanics Lab conducts studies with the purpose of comparing the properties and performance of …


Uplc-Ms/Ms Analysis Of The Michaelis-Menten Kinetics Of Cyp3a-Mediated Midazolam 1′- And 4-Hydroxylation In Rat Brain Microsomes, Devaraj Venkatapura Chandrashekar, Barent Dubois, Reza Mehvar Aug 2021

Uplc-Ms/Ms Analysis Of The Michaelis-Menten Kinetics Of Cyp3a-Mediated Midazolam 1′- And 4-Hydroxylation In Rat Brain Microsomes, Devaraj Venkatapura Chandrashekar, Barent Dubois, Reza Mehvar

Pharmacy Faculty Articles and Research

Midazolam (MDZ) is a short-acting benzodiazepine with rapid onset of action, which is metabolized by CYP3A isoenzymes to two hydroxylated metabolites, 1′-hydroxymidazolam and 4-hydroxymidazolam. The drug is also commonly used as a marker of CYP3A activity in the liver microsomes. However, the kinetics of CYP3A-mediated hydroxylation of MDZ in the brain, which contains much lower CYP content than the liver, have not been reported. In this study, UPLC-MS/MS and metabolic incubation methods were developed and validated for simultaneous measurement of low concentrations of both hydroxylated metabolites of MDZ in brain microsomes. Different concentrations of MDZ (1–500 µM) were incubated with …


Amphiphilic Cell-Penetrating Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Saghar Mozaffari Dec 2019

Amphiphilic Cell-Penetrating Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Saghar Mozaffari

Pharmaceutical Sciences (PhD) Dissertations

A number of cyclic peptides containing a positively charged ring composed of arginine residues attached to hydrophobic tail made of tryptophan residues through a lysine linker namely [R5K]W5, [R6K]W5, [R5K]W6, [R7K]W5, [R5K]W7, [R6K]W6, and [R7K]W7 were synthesized and evaluated as molecular transporters. The peptides were evaluated for their ability to deliver, fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F′-GpYEEI), and fluorescent labeled anti-HIV drugs (F′-FTC and F′-d4T). The results indicated that the presence of positively …


Studies Of Amino Acid Mutations In Drug Resistance Of The Smo Protein, Eunice Wintona Mar 2018

Studies Of Amino Acid Mutations In Drug Resistance Of The Smo Protein, Eunice Wintona

UNO Student Research and Creative Activity Fair

Smoothened receptor (SMO) is a protein that in humans, is encoded by the SMO gene. A systemic mutation in its binding pocket helps predict the sensitivity of mutant proteins to different drugs. Known as a GPCR-like receptor, it is a component of the hedgehog signaling pathway; a pathway involved in body patterning and the regulation of adult stem cells. An uncontrolled or inappropriate activation of the Hedgehog pathway drives tumor progression in cancers and a number of birth defects. To achieve these goals, the molecular modeling software MOE was used to build small molecules and drug molecules like Vismodegib and …


Tumor-Targeted Delivery Of Sirna Using Fatty Acyl-Cgkrk Peptide Conjugates, Meenakshi Sharma, Naglaa Salem El-Sayed, Hung Do, Keykavous Parang, Rakesh Tiwari, Hamidreza Montazeri Aliabadi Jul 2017

Tumor-Targeted Delivery Of Sirna Using Fatty Acyl-Cgkrk Peptide Conjugates, Meenakshi Sharma, Naglaa Salem El-Sayed, Hung Do, Keykavous Parang, Rakesh Tiwari, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

Tumor-targeted carriers provide efficient delivery of chemotherapeutic agents to tumor tissue. CGKRK is one of the well-known tumor targeting peptides with significant specificity for angiogenic blood vessels and tumor cells. Here, we designed fatty acyl conjugated CGKRK peptides, based on the hypothesis that hydrophobically-modified CGKRK peptide could enhance cellular permeation and delivery of siRNA targeted to tumor cells for effective silencing of selected proteins. We synthesized six fatty acyl-peptide conjugates, using a diverse chain of saturated and unsaturated fatty acids to study the efficiency of this approach. At peptide:siRNA weight/weight ratio of 10:1 (N/P ≈ 13.6), almost all the peptides …


Synthesis And Evaluation Of Antimicrobial Activity Of [R4w4k]-Levofloxacin And [R4w4k]-Levofloxacin-Q Conjugates, Neda Riahifard, Kathy Tavakoli, Jason Yamaki, Keykavous Parang, Rakesh Tiwari Jun 2017

Synthesis And Evaluation Of Antimicrobial Activity Of [R4w4k]-Levofloxacin And [R4w4k]-Levofloxacin-Q Conjugates, Neda Riahifard, Kathy Tavakoli, Jason Yamaki, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

The development of a new class of antibiotics to fight bacterial resistance is a time-consuming effort associated with high-cost and commercial risks. Thus, modification, conjugation or combination of existing antibiotics to enhance their efficacy is a suitable strategy. We have previously reported that the amphiphilic cyclic peptide [R4W4] had antibacterial activity with a minimum inhibitory concentration (MIC) of 2.97 g/mL against Methicillin-resistant Staphylococcus aureus (MRSA). Herein, we hypothesized that conjugation or combination of the amphiphilic cyclic peptide [R4W4] with levofloxacin or levofloxacin-Q could improve the antibacterial activity of levofloxacin and levofloxacin-Q. Fmoc/tBu solid-phase chemistry was employed to synthesize conjugates of …


Engineered Peptides For Applications In Cancer-Targeted Drug Delivery And Tumor Detection, R. Soudy, N. Byeon, Y. Raghuwanshi, S. Ahmed, A. Lavasanifar, Kamaljit Kaur Jan 2017

Engineered Peptides For Applications In Cancer-Targeted Drug Delivery And Tumor Detection, R. Soudy, N. Byeon, Y. Raghuwanshi, S. Ahmed, A. Lavasanifar, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Cancer-targeting peptides as ligands for targeted delivery of anticancer drugs or drug carriers have the potential to significantly enhance the selectivity and the therapeutic benefit of current chemotherapeutic agents. Identification of tumor-specific biomarkers like integrins, aminopeptidase N, and epidermal growth factor receptor as well as the popularity of phage display techniques along with synthetic combinatorial methods used for peptide design and structure optimization have fueled the advancement and application of peptide ligands for targeted drug delivery and tumor detection in cancer treatment, detection and guided therapy. Although considerable preclinical data have shown remarkable success in the use of tumor targeting …


Characterization Of The Role That Alternative Ribonucleotide Reductases Play In Restoring Replication In The Presence Of Hydroxyurea In Escherichia Coli, Michael Sadek Jun 2015

Characterization Of The Role That Alternative Ribonucleotide Reductases Play In Restoring Replication In The Presence Of Hydroxyurea In Escherichia Coli, Michael Sadek

PSU McNair Scholars Online Journal

DNA replication is essential for cells to grow and divide. Ribonucleotide reductase is an essential enzyme that is responsible for the formation of deoxyribonucleotides that are used in DNA synthesis during replication. Hydroxyurea is a chemotherapeutic agent that is thought to work by specifically inhibiting the ribonuceotide reductase to prevent replication. However, recent studies in E. coli have shown that following an initial period of inhibition, DNA synthesis then recovers in the presence of hydroxyurea, suggesting that the mode of death and cellular response to hydroxyurea is more complex than originally proposed. The E.coli genome encodes three ribonucleotide reductases that …


Accidental Phosphine Gas Poisoning With Fatal Myocardial Dysfunction In Two Families, Saleem Akhtar, Arshalooz Rehman, Surraya Bano, Anwarul Haque May 2015

Accidental Phosphine Gas Poisoning With Fatal Myocardial Dysfunction In Two Families, Saleem Akhtar, Arshalooz Rehman, Surraya Bano, Anwarul Haque

Department of Emergency Medicine

ABSTRACT Aluminum phosphide is commonly used as a rodenticide and insecticide and is one of the most fatal poisons. The active ingredient is Phosphine gas which inhibits cytochrome oxidase and cellular oxygen utilization. The clinical symptoms are due to multiorgan involvement including cardiac toxicity which is the most common cause of mortality. Severity of clinical manifestations depends upon the amount of the gas to which a person is exposed. There is no specific antidote available. High index of suspicion and early aggressive treatment is the key to success. We report 2 cases of aluminum phosphide toxicity in 2 families due …


Tuning Responsiveness Of Polypeptide Based Block Copolymers For Drug Delivery, Ashley J. Johnson Dec 2014

Tuning Responsiveness Of Polypeptide Based Block Copolymers For Drug Delivery, Ashley J. Johnson

Dissertations

The goal of this dissertation was to tune the pH response and self-assembled morphologies of amphiphilic polypeptide block copolymers for use as drug delivery vehicles. Poly(L-lysine) and poly(L-glutamtic acid) are responsive, ionizable polypeptides that undergo secondary structure transitions, from α-helix to random coil, whereby the change in conformation of the peptide chain results in changes to the global morphology of a self-assembled system. The main focus of this work was to understand how changes in the polymer composition and the local environment can lead to control over the behavior of the overall system. First, the responsive behavior of poly(L-lysine) block …