bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decreased Cell Proliferation with 2, 3‐ Dichloro‐5, 8‐Dimethoxy‐1, 4‐Naphthoquinone and 4‐Hydroxy Tamoxifen in Triple Negative Breast Cancer Cell Lines
Authors: Robinson Anastasia G.J. , Copeland Robert L. 
Published: April 2020

Triple negative breast cancer (TNBC) is a subtype of breast cancer (BC) that makes up 10–15% of BC diagnosis. This form of the disease disproportionately affects African American (AA) women as compared to women of other ethnicities. TNBC is classified by lack of expression of three receptors: Estrogen alpha (ERα), progesterone (PR) and human epidermal growth factor 2 (HER2). These receptors are used as therapeutic targets for BC that express them. As specific targets are not present, surgery, radiation and chemotherapy have been the mainstay of therapy for TNBC. Recently, newer drugs have become available based on specific genetic and epigenetic mutations like BRCA1, however more treatment options need to be produced to reduce the mortality rate in this disease. A novel compound, 2, 3‐dichloro‐5, 8‐dimethoxy‐1, 4‐naphthoquinone (Z285) belongs to the class of naphthoquinones that demonstrate activities as anticancer, antimalarial, and antibacterial compounds. These compounds have also been shown to cause an increase in reactive oxygen species (ROS) production as well as affect signaling pathways associated with epidermal growth factor receptor (EGFR). Moreover, it has been reported that treatment with tamoxifen can cause cell death. This is based on the accumulation of the drug and its active metabolites within cells that may cause an increase in the ROS production ultimately leading to cellular death, even in ERα negative cell lines.In the current study, three triple negative cell lines, HCC1806, MDA MB 231 and HS578T were used. These cells were treated with Z285 and 4‐hydroxy tamoxifen (4OH‐Tam) for 24 or 72hr with 1, 2, 4, 8, 16μM and 3, 6, 12, 24, 48μM respectively. Synergestic activity was demonstrated using SynergyFinder as well as the Chou‐Talalay method (CompuSyn). In other experiments, cells were treated with the IC50 of Z285 which was established in prior experiments. mRNA and protein were isolated between 6 and 24hr. Results showed alterations of several mRNA in response to these treatments. In addition, there were modifications to Nrf2 protein concentration, a transcription factor associated with oxidative stress. Therefore, these results indicate that combination treatment of Z285 and 4OH‐Tam induce cell death at lower concentrations. Thus this novel compound which causes an increase in ROS in these TNBC cells, may render them more susceptible to tamoxifen therapy.Support or Funding InformationCharles and Mary Latham Fund
Characterization of Desulfinase for the Removal of Recalcitrant Sulfur Compounds in Petroleum
Authors: Dodd Cameron 
Published: April 2020

Biodesulfurization provides a method to remove the sulfur from organosulfur compounds found in petroleum. This multi‐step pathway is able to remove sulfur from dibenzothiophene (DBT), one of the most recalcitrant compounds found in petroleum and crude oil. A critical enzyme in this pathway is an aromatic desulfinase (DszB) that catalyzes the final rate‐limiting step of the desulfurization. The DszB enzyme from Nocardia asteroides A3H1 was overexpressed in E. coli, purified using Ni2+‐affinity chromatography and characterized kinetically. Kinetic assays revealed a sigmoidal response when the velocity was plotted against substrate concentration, calling into question the monomeric structure of the enzyme previously reported by crystallography studies. Size exclusion chromatography and cross‐linking experiments were conducted to further investigate the oligomerization of HPBS desulfinase. Attempts to further purify the enzyme using Co2+‐affinity chromatography provided further evidence that under certain conditions DszB may exhibit cooperativity.Support or Funding InformationJMU Department of Chemistry and Biochemistry Dr. Linette M. Watkins NSF Grant No. CHE‐1757874
An Anti‐Mesothelin Recombinant Immunotoxin Based on Deoxyribonuclease‐I
Authors: Sprehe Ruby , Baker Jillian , Weldon John 
Published: April 2020

Recombinant immunotoxins (RITs) are fusion proteins consisting of a toxin attached to an antibody fragment. Unlike traditional chemotherapy, RITs used in cancer therapy can be specifically targeted to tumor cells while sparing healthy cells. One shortcoming of RITs is their immunogenicity, which is the immune response of patients to treatment with RITs. Patients with intact immune systems often produce antibodies to the toxin that neutralize its function. For this experiment, we attempted to prepare a RIT using deoxyribonuclease‐ I (DNase‐I) instead of a typical bacterial or plant‐derived toxin. DNase‐I is an endogenous human protein that catalyzes the degradation of DNA into its component nucleotides. Previous research shows that DNase‐I can be toxic to cells if delivered through targeted endocytosis. Furthermore, we predict that DNase‐I will be less immunogenic than other toxins, because it is a human protein. We successfully cloned an expression vector joining DNase‐I to an anti‐mesothelin antibody fragment and expressed it in E. coli. The resulting protein, however, was unstable and we were unable to purify it after refolding from inclusion bodies. We concluded that the design of the fusion protein needs improvement to enhance its stability. It is also possible that the refolding conditions need further optimization. Future directions include exploring both of these possibilities.Support or Funding InformationI would like to thank the Towson Bridges Program and CCBC for the opportunity. Thank you to Dr. Laing, Dr. Snyder, Dr. Berlyn and Trudymae for guidance throughout the program. Thank you to the NIH Bridges Grant 5 R25 GM058264 16 for funding. Special thanks to Dr. Weldon, Jillian Baker and all students that have helped throughout the project.
Antioxidant Activities of Green Synthesized Zinc Oxide Nanoparticles and its Curative Influence in Carbon tetrachloride‐Induced Hepatorenal Damage in Adult Rats
Authors: Otuechere Chiagoziem A. , Ekozin Adriel , Adewuyi Adewale 
Published: April 2020

The objective of this study was to synthesize Zinc Oxide nanoparticles coated with Pterocarpus mildbraedii leaf extracts (PmZnONPs) by an eco‐friendly method, and investigate its antioxidant activity and curative potential against carbon tetrachloride (CCl4) ‐ induced hepatorenal toxicity in rats. PmZnONPs was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), fourier transform infra‐red spectroscopy (FTIR), alongside zeta potential measurement. In vitro, free radical activities using 1, 1‐diphenyl‐2‐ picrylhydrazyl (DPPH) and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS) showed strong antioxidant activity compared to ascorbic acid. In rats, PmZnONPs (1 and 3 mg/kg p.o.) significantly prevented CCl4‐induced elevations of alkaline phosphatase, gamma‐glutamyl transferase, creatinine, urea, aspartate aminotransferase, alanine aminotransferase, and total bilirubin. Moreover, PmZnONPs restored the decreased levels of plasma uric acid, hepatorenal antioxidant enzymes, including superoxide dismutase, glutathione peroxidase, glutathione transferase, and glutathione, that were significantly induced by CCl4 treatment. Histological studies indicated that CCl4‐induced lesions in the liver and kidney were alleviated by the treatment of PmZnONPs. Immunohistochemical studies showed that PmZnONPs significantly suppressed the high immunoreactivity of cyclooxygenase‐2, interleukin‐6 and NF‐κB arising from CCl4 intoxication. These results indicated that PmZnONPs protected the rats from CCl4‐induced hepatorenal damage via its antioxidant properties as well as its inhibition of pro‐inflammatory proteins.Support or Funding InformationThis research did not receive any support from any funding organization.
Assessment of Collagen Metabolism by Human Gingival Fibroblasts Reared in Serum‐free Conditions
Authors: Laird Patrick , Mattioli Patrisia , Maloney Trevor J. , Otto Ashley , Musiol Joseph , Nguyen Stephanie , Popper Hannah , Morris Gregory Philip , Beqo Belinda , Isaac Tamika , Green Kevan , Shamseddin Seyed , Borghaei Ruth , D’Angelo Marina 
Published: April 2020

Periodontal disease is present in 48% of people over the age of 30 years and 70% over the age of 65 years. It is marked by an inflammatory state that affects the gum tissue, periodontal ligaments, and the alveolar bone itself. It has several different causes, but a significant risk factor is smoking because it impairs the healthy biological pathway of repair of the tissues. In a generally healthy patient, there is a balance of broken down collagen and repair with intact collagen. The enzyme responsible for this collagen type 1 degradation is matrix metalloproteinase‐8 (MMP‐8). In this study, the metabolic activity of primary human gingival fibroblasts (HGVF) isolated from inflamed non‐smoker (IFN) and inflamed smoker (IFC) were cultured in serum‐free media over a 48 hour period. We measured production of intact and degraded collagen type I in the secreted fraction (conditioned media) and in the incorporated extracellular matrix. In the secreted and incorporated fractions at both time points (24 and 48hr), HGVF isolated from a smoker (IFC) produced more intact collagen (100% more secreted and incorporated) and more degraded collagen (97% more secreted and 95% more incorporated) than HGVF isolated from the non‐smoker (IFN) (p<0.001). These data support the hypothesis that inflamed tissue isolated from a current smoker exhibits a profile of collagen metabolism in line with more acute diseased state (fibrotic collagen profile). In addition, the culture of primary human gingival fibroblasts in serum‐free medium for at least 48 hours is a viable method to study the disease mechanism of periodontitis and potential therapeutics to treat the disease.Support or Funding InformationThis work is supported by the Division of Research at PCOM
Non‐Tuberculous Mycobacteria Infections Increase NOS2 While Decreasing NO Levels
Authors: Lin Kuo-Chuan , Bedi Brahmchetna , Sadikot Ruxana T. , Sutliff Roy 
Published: April 2020

Non‐tuberculous mycobacteria (NTM) are rod‐shaped bacilli that cause lung infections in patients with weakened immune system or underlying lung disease such as cystic fibrosis, COPD, or prior tuberculosis. While it is well‐established that NTM cause lung disease, the host response to infection with NTM has not been well‐characterized. The production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) by innate immune cells is considered a major defense mechanism against mycobacteria. Nitric oxide (NO), a product of inducible nitric oxide synthase (NOS2) in macrophages, plays an essential role in M. tuberculosis (MTb) infection through its bactericidal and anti‐inflammatory characteristics. Therefore, we hypothesized that NTM infection may upregulate NOS2 expression, which in turn may contribute to the host response to NTM infection. RAW 264.7 and MH‐S cells, virus transformed murine macrophages and alveolar macrophages, respectively, were exposed to NTM (M. avium‐intracellulare, or MAI) at a MOI of 25 and NO levels in cell media were monitored 4, 8, 12, 24, and 48 hours after NTM infection using a colorimetric GSNO assay. mRNA expression of NOS isoforms (NOS1, NOS2, and NOS3) in MH‐S and RAW cells were analyzed 24‐ and 48‐hours post‐infection. MH‐S cells were also transfected with siRNA to NOS2 and infected with MAI for 0.5, 4, and 24 hours, and their intracellular NTM were quantified to assess macrophage function. NO levels decreased following 4 hours of NTM exposure and remained decreased for 48 hours (P<0.05). NTM infection increased the expression of NOS2 without affecting levels of other NOS isoforms (P<0.05). siNOS2 transfected cells infected with MAI for more than four hours had significantly greater levels of intracellular MAI compared to scrambled negative control (P<0.05). Our preliminary data are the first to demonstrate that NTM increase NOS2 expression while decreasing NO levels. Furthermore, decreasing NOS2 expression exacerbates NTM infections. Future studies will examine mechanisms whereby NTM decrease NO levels. Therefore, we propose that approaches that restore NO can enhance macrophage host defense against NTMs and improve infection clearance.Support or Funding InformationThis work was supported in part by NIH Grant R01HL102167 (RLS), Merit Review funding from the Department of Veteran’s Affairs, Office of Research and Development (RTS). NTM isolates are Isolates were provided by Emory University Hospital
Chronic Ablation of Hindlimb Afferents Containing TRPV1 Receptors Attenuates Cardiovascular Responses to Muscle Metaboreflex Activation
Authors: Mannozzi Joseph Thomas , Senador Danielle , Al-Hassan Mohamed , Lessanework Beruk , Alvarez Alberto , O’Leary Donal S. 
Published: April 2020

Increases in sympathetic nerve activity during exercise occur, in part, due to activation of the muscle metaboreflex – a pressor reflex triggered via stimulation of type III and IV skeletal muscle afferents. Some of these afferents express capsaicin sensitive transient receptor potential vanilloid 1 (TRPV1) channels. Epicardial and intrathecal administration of resiniferatoxin (RTX), an ultra‐potent analog of capsaicin, attenuates responses to cardiac sympathetic afferent activation and provides relief of limb pain due to bone cancer. We investigated whether administration of intrathecal RTX (2μg/kg, L4–L6) would attenuate the muscle metaboreflex (induced by partial reductions in hindlimb blood flow during steady‐state mild exercise; 3.2 km/h). Experiments were performed using conscious, chronically instrumented canines before and 10–42 days after RTX. RTX markedly attenuated metaboreflex‐induced increases in mean arterial pressure (+27.0 ± 5.0 mmHg vs. +5.9 ± 8.2 mmHg) and cardiac output (+1.40 ± 0.20 l/min vs. +0.28 ± 0.12 l/min). Terminal experiments under isoflurane anesthesia performed 78 ± 14 days after RTX showed attenuated pressor responses to hindlimb intra‐arterial infusion of 20μg/kg capsaicin (+45.7 ± 6.5 mmHg pre RTX vs. +19.7 ± 3.1 mmHg post RTX). We conclude that intrathecal RTX chronically attenuates muscle metaboreflex pressor responses. Thus, RTX could be an effective treatment to reduce excessive sympatho‐activation often seen during exercise in patients with heart failure or other diseases when the metaboreflex is overstimulated due to underperfusion of the active skeletal muscle.Support or Funding InformationHL‐55473, HL‐126706, HL‐120822 and GM‐058905
Salt‐dependent protein splicing of an intein from the halophile Haloferax volcanii
Authors: Cawood Alexandra , Ruiz Mercedes , Mills Kenneth 
Published: April 2020

Protein splicing is a post‐translational process facilitated by an intervening polypeptide called an intein, or internal protein. The intein is located between two flanking polypeptides, called exteins. The intein catalyzes its excision from the extein concomitant with the ligation of the exteins. The extremophile Haloferax volcanii grows in high salt environments. We are interested in the salt‐dependence of the protein splicing and nuclease activity of the intein that has invaded its DNA Polymerase beta gene. We have shown that we can induce protein splicing of the intein in vitro as a function of salt concentration and time. The intein has an intervening homing endonuclease domain and we are interested to learn if mutations within this domain would influence splicing. Characterization of a conditionally‐active nuclease may have utility in biotechnology applications.Support or Funding InformationThis work was supported by the National Science Foundation (grant MCB‐1517138), National Institutes of Health (grant 1R15GM132817‐01), and by the Camille & Henry Dreyfus Foundation
Cardiac and Medullary Neuroinflammatory Pathways Trigger Androgenic Incitement of Cardiovascular Sequels of Endotoxemia in Rats
Authors: Sallam Marwa Y. , El-Gowilly Sahar M. , El-Mas Mahmoud M. 
Published: April 2020

Inconsistent reports are available on the role of testosterone in end organ damage caused by endotoxemia. Here, pharmacologic, surgical, and molecular studies were employed to assess the testosterone modulation of cardiovascular and autonomic derangements caused by endotoxemia and the role of peripheral and central inflammatory pathways in this interaction. Studies were performed in conscious male rats pre‐instrumented with femoral indwelling catheters for hemodynamic monitoring and subjected to castration or pharmacologic interventions that interrupt the biosynthetic cascade of testosterone. Compared to the effects of lipopolysaccharide (LPS, 10 mg/kg i.v.) in sham operated rats, 2‐week castration significantly reduced the LPS‐evoked: (i) falls in blood pressure, (ii) decreases in time‐ and frequency domain indices of heart rate variability (HRV), (iii) shifts in cardiac sympathovagal balance towards parasympathetic dominance as evidenced by decreases in low‐frequency to high‐frequency ratio of spectral powers, and (iii) increases in protein expressions of toll‐like receptor 4 and monocyte chemoattractant protein‐1 in the heart as well as in medullary neurons of the nucleus tractus solitarius and rostral ventrolateral medulla. The favorable influences of castration on inflammatory and cardiovascular abnormalities of endotoxemia were replicated in intact rats pretreated with degarelix (gonadotropin‐releasing hormone receptor blocker) or finasteride (5α‐reductase inhibitor), but not formestane (aromatase inhibitor). The data signifies the importance of testosterone and its biosynthetic enzymes in cardiovascular and autonomic insults induced by the endotoxic inflammatory response. Clinically, the interruption of testosterone biosynthesis could offer a potential therapeutic strategy for endotoxemia.Support or Funding InformationSupported by the Science and Technology Development Fund, Egypt (STDF Grants No. 14895)
Sympathomotor activation by midbrain locomotor neurons is mediated through glutamate release in the rostral ventrolateral medulla
Authors: Koba Satoshi , Kumada Nao , Watanabe Tatsuo 
Published: April 2020

Our pilot data showed that a portion of neuronal cells in the mecencephalic locomotor region (MLR) sends axonal projections to the rostral ventrolateral medulla (RVLM) (MLR‐RVLM pathway), being capable of eliciting sympathomotor activation in rats. Here, we examined the effect of ionotropic glutamate receptor blockade in rat RVLM on sympathomotor activation by the MLR‐RVLM pathway. Male rats received microinjections bilaterally in the RVLM with a retrograde adeno‐associated virus that encoded a channelrhodopsin with green fluorescence protein. Under anesthesia, 473 nm wavelength laser illumination of the MLR after administration in the RVLM with a cocktail of AP5 and CNQX, NMDA and AMPA glutamate receptor blockers, respectively, elicited 29% less (P < 0.05) renal sympathoexcitation than that after saline administration. Likewise, under decerebration without anesthesia, ventral root fiber excitation in response to MLR photostimulation seen after saline administration in the RVLM was suppressed to a 35% extent (P < 0.05) by preliminarily administration of the glutamate receptor blockers. These observations suggest that glutamatergic neurons in the MLR‐RVLM pathway function in generating central command function.Support or Funding InformationSupported by JSPS KAKENHI 18H03151 (S. Koba).
Inconsistent effects of surgical and chemical castration on arterial baroreceptor dysfunction and cardiac and brainstem inflammation in endotoxic rats
Authors: Sallam Marwa Y. , El-Gowilly Sahar M. , El-Mas Mahmoud M. 
Published: April 2020

Impaired cardiac autonomic and arterial baroreflex activity has been implicated in cardiovascular derangements induced by endotoxemia. In this communication, we tested the hypothesis that androgenic hormones contribute to endotoxic manifestations of arterial baroreflex dysfunction and related cardiac and central neuroinflammatory pathways in male rats. Baroreflex curves relating changes in heart rate to increases or decreases in blood pressure evoked by phenylephrine (PE) and sodium nitroprusside (SNP), respectively, were constructed in conscious sham‐operated and castrated rats treated with or without lipopolysaccharide (LPS, 10 mg/kg i.v.). Slopes of baroreflex curves were used as measures of baroreflex sensitivity (BRS). In sham rats, LPS caused significant reductions in BRS and increases in the immunohistochemical expression of NFκB in cardiac tissues as well as in brainstem neurons of the nucleus tractus solitarius (NTS) and rostral ventrolateral medulla (RVLM). The baroreflex depressant effect of LPS was maintained in CAS rats despite significant attenuation of the inflammatory response in cardiac and brainstem areas. We also evaluated the effects of pharmacologic inhibition of androgenic biosynthetic pathways on LPS responses. Whereas none of the LPS effects were altered after prior exposure to formestane (aromatase inhibitor, 15 mg/kg s.c)‐pretreated rats, the LPS‐evoked BRSPE, but not BRSSNP, depression and cardiac and neuronal inflammation disappeared in intact rats pretreated with degarelix (gonadotropin‐releasing hormone receptor blocker, 1 mg/kg s.c.). On the other hand, the prior inhibition of 5α‐reductase by finasteride (20 mg/kg s.c) did not affect baroreflex dysfunction induced by LPS and reduced cardiac, but not neuronal, NFκB expression. The data highlight advantageous effects for the inhibition of hypothalamic‐pituitary‐gonadal axis in counteracting baroreflex dysfunction caused by endotoxemia and predisposing cardiac and neuroinflammatory signals.Support or Funding InformationSupported by the Science and Technology Development Fund, Egypt (STDF Grant No. 14895)
Investigating the Effects of Gpa2 Phosphorylation on Yeast Sporulation
Authors: Cheranda Nina Kiran , Huang Shan , Wang Yuqi 
Published: April 2020

Gpa2 is a G alpha protein in budding yeast, Saccharomyces cerevisiae, that functions in the nutrient signaling pathway. In diploid yeast cells, Gpa2 interacts with the cytoplasmic protein Ime2 and acts as an inhibitor to prevent Ime2 from inappropriate activation of sporulation. It is unclear how the inhibitory effect of Gpa2 on Ime2 is regulated. Recently, we found that Gpa2 undergoes phosphorylation and that its level of phosphorylation increases upon nitrogen starvation, a condition that triggers sporulation in yeast. Interestingly, phosphorylation enhances plasma membrane localization of Gpa2, raising the possibility that Gpa2 phosphorylation may play a role in the regulation of yeast sporulation. Accordingly, we investigated the sporulation efficiency of diploid cells that express either wild type Gpa2 or Gpa2‐10SA mutant, which lacks 10 serine residues required for phosphorylation. Using confocal microscopy to analyze the cells with clear indicators of the presence of spores, we found that more cells expressing wild type Gpa2 underwent sporulation than cells expressing Gpa2‐10SA mutant did. Our findings suggest that regulated phosphorylation of Gpa2 is a potential mechanism that relieves the inhibitory effect of Gpa2 on Ime2.Support or Funding InformationKnoedler Undergraduate Fund from Saint Louis University