bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced Aggressiveness of Bystander Cells in an Anti‐tumor Photodynamic Therapy Model: Role of Nitric Oxide Produced by Targeted Cells
Authors: Girotti Albert , Bazak Jerzy , Fahey Jonathan , Korytowski Witold 
Published: November 2023

The bystander effects of anti‐cancer ionizing radiation have been widely studied, but far less is known about such effects in the case of non‐ionizing photodynamic therapy (PDT). In the present study, we tested the hypothesis that photodynamically‐stressed prostate cancer PC3 cells can elicit nitric oxide (NO)‐mediated pro‐growth/migration responses in non‐stressed bystander cells. A novel approach was used whereby both cell populations existed on a culture dish, but made no physical contact with one other. Visible light irradiation of target cells sensitized with 5‐aminolevulinic acid‐induced protoporphyrin IX resulted in a striking upregulation of inducible nitric oxide synthase (iNOS) along with NO, the level of which increased after irradiation. Slower and less pronounced iNOS/NO upregulation was also observed in bystander cells. Activation of transcription factor NF‐κB was implicated in iNOS induction in both targeted and bystander cells. Like surviving targeted cells, bystanders exhibited a significant increase in growth and migration rate, both responses being strongly attenuated by an iNOS inhibitor (1400W), a NO scavenger (cPTIO), or iNOS knockdown. Incubating bystander cells with conditioned medium from targeted cells failed to stimulate growth/migration, ruling out involvement of relatively long‐lived stimulants. The following post‐irradiation changes in pro‐survival/pro‐growth proteins were observed in bystander cells: upregulation of COX‐2 and activation of protein kinases Akt and ERK1/2, NO again playing a key role. This is the first reported evidence for NO‐enhanced bystander aggressiveness in the context of PDT. In the clinical setting, such effects could be averted through pharmacologic use of iNOS inhibitors as PDT adjuvants.Support or Funding InformationNIH/NCI Grant CA70823
H/D exchange mass spectrometry reveals calmodulin‐controlled regulatory interactions in neuronal nitric oxide synthase
Authors: Carley Jeffrey R , Barrett Morgan F , Gilbreath Tyler J , Underbakke Eric S 
Published: November 2023

Neuronal nitric oxide synthase (nNOS) produces nitric oxide (NO), a unique signaling gas molecule involved in retrograde neuronal signaling. Homodimeric nNOS is composed of a reductase and oxidase subdomain, connected by a mobile FMN subdomain. The reductase domain delivers reducing equivalents from NADPH through FAD and FMN to the heme of the oxidase domain, where NO is generated from arginine. Delivery of reducing equivalents is tightly regulated by Ca2+ via the intermediary Ca2+‐sensor calmodulin (CaM). We examined conformational changes induced by CaM‐binding that encourage the inter‐domain delivery using hydrogen‐deuterium exchange mass spectrometry (HDX‐MS).HDX‐MS revealed critical regulatory surfaces on the reductase domain and FMN subdomain. In particular, two highly localized regions exhibited CaM‐induced increase in exchange rates. Changes in the reductase domain were most pronounced in a regulatory beta‐finger, a structural element unique to the CaM‐regulated isoforms of NOS. Interestingly, the CaM‐perturbed regions encompass two serine residues that are subject to phosphorylation, a modification reported to tune nNOS activity. Changes in the mobile FMN subdomain were more distributed largely localized to the distal surface opposite the FMN cofactor. This surface includes an auto‐inhibitory insert involved in docking the FMN subdomain to the reductase domain. Taken together, the HDX‐MS results define several inter‐domain interaction surfaces that are released upon Ca2+/CaM‐induced activation.
Effect of Methyglyoxal and Curcumin on PC12 and RINm5f Cells
Authors: de Castro Victoria Puccini , Keys Steven , Su Jing , Mungre Sue 
Published: November 2023

Uncontrolled diabetes can lead to several serious complications such as kidney failure, atherosclerosis and neuropathy. Methylglyoxal (MG), a highly reactive compound derived from glucose and fructose metabolism has been implicated as the causative agent in these complications. Our work with neuronal PC12 cells has shown that MG treatment caused death of 60% of PC12 cells within 24 hours. It also increased the activity of inducible nitric oxide synthase (iNOS) and caspase‐3, suggesting that MG causes apoptotic cell death via oxidative stress. Curcumin, an antioxidant from the spice Curcuma longa, prevented cell death and the inhibited the activity of iNOS and caspase‐3. Oxidative stress is also reported to cause ER stress resulting in unfolded protein response (UPR). To determine whether it occurs in PC12 cells, we studied the effect of MG on the expression of CHOP and Bip, genes involved in UPR using qPCR. MG treatment increased the expression of CHOP by 20 fold and that of BiP by 10 fold. Treatment with curcumin partially reversed the effect, indicating that MG caused ER stress in PC12 cells. We extended these studies to RINm5f, a pancreatic beta cell line. Diabetic conditions have been reported to cause dysfunction of beta cells. Our preliminary studies show that there was 60–70% death in MG treated RINm5f cells, suggesting that similar oxidative stress/ER stress mechanism may be involved.Support or Funding InformationCOR grant from Northeastern Illinois University
Pro‐death Bax Has an Intrinsic Capability to Induce Aggregate‐dependent Caspase 8‐mediated Cell Death
Authors: Manas Adriana , Wang Sheng , Li Jiajun , Nelson Adam , Davis Aislinn , Lamerand Sydney , Zhang Huaiyuan , Xiang Jialing 
Published: November 2023

BaxΔ2 is a unique functional Bax isoform resulted from the combination of a mononucleotide deletion and an alternative splicing in the N‐terminus. The rest of the sequence is the same between Baxα and BaxΔ2. However, BaxΔ2 is unable to target mitochondria due to the loss of helix α1, encoded by exon 2. Instead, it forms cytosolic aggregates to activate caspase 8‐dependent death pathway. The functional domains involved in BaxΔ2 aggregation and cytotoxicity remained elusive. Using computational modeling in combination with biochemical and cellular analysis, we show here that the drastic changes in the BaxΔ2 N‐terminus have no significant impact on either aggregation or caspase 8 activation. In addition, the hallmark BH3‐killing domain is necessary but not sufficient for either aggregation or cell death. The intact core region of BaxΔ2 encoded by exons 3, 4, and 5 is required for the formation of large aggregates, which are essential for BaxΔ2 cytotoxicity. Surprisingly, aggregation by itself is still not sufficient to trigger cell death. The C‐terminal end encoded by exon 6 is essential for activation of caspase 8. Finally, the C‐terminal conformation, but not the primary sequence, appears to be responsible for the aggregate‐mediated caspase 8 activation and cell death. As Baxα with deletion of exon 2 behaves the same as BaxΔ2, and also shares the same C‐terminus sequence or conformational motifs with most Bax‐isoform family members, these results imply that Bax isoforms may have an intrinsic ability to activate caspase 8 if they fail to target mitochondria.Support or Funding InformationThis work is supported by NIH R15CA195526 grant
Leveraging Synthetic Lethality to Target Convergent Therapeutic Resistance
Authors: Wood Kris C 
Published: November 2023

Our laboratory uses genomic and pharmacological methods to define the pathways of resistance to targeted anticancer therapies. Toward this end, we recently developed a technique in which engineered lentiviral cDNAs encoding activators of major oncogenic signaling pathways are introduced into cells and then profiled to identify those capable of conferring resistance to drugs (Science Signaling 2014, 7, ra121). In parallel, we have also developed analogous loss‐of‐function screening approaches based on CRISPR/Cas9 gene editing, and have used these approaches to map the pathways supporting intrinsic resistance to targeted therapies. Using these tools in conjunction with data and mouse models derived from human tumors, we recently discovered that major pathways of resistance frequently converge onto common downstream effectors, the targeting of which can forestall resistance. Here, I will describe the discovery of common resistance effectors in JAK2‐driven myeloproliferative neoplasms, EGFR‐driven colorectal cancers, and BRAF‐driven melanomas (Science Signaling 2014, 7, ra122; Nature Communications 2015, 6, 8305). Focusing particularly on melanoma, I will describe the discovery that major pathways of resistance converge to activate the transcription factor c‐MYC (MYC). MYC expression and gene signatures were suppressed following initial drug treatment, then rebounded during tumor progression in each member of a large panel of human patients, independent of the upstream pathway driving resistance. MYC suppression using either genetic approaches or BET bromodomain inhibition was sufficient to both resensitize diverse BRAFi/MEKi‐resistant models and delay resistance in treatment naïve models. Although direct pharmacological inhibition of MYC remains difficult, the BRAFi/MEKi‐resistant, MYC‐activated state harbors synthetic lethal signaling and metabolic dependencies, including those involving SRC family and c‐KIT tyrosine kinases and glucose, glutamine, and serine pathways, that can be targeted to create combination therapies that uniquely select against resistance evolution.Support or Funding InformationNIH Building Interdisciplinary Research Careers in Women's Health Program (K12HD043446)Stewart Trust Fellowship (K.C.W.)V Scholar Award from the V Foundation for Cancer Research (K.C.W.)DoD Breast Cancer Research Program Breakthrough Award (BC151664) (K.C.W) NIH/NCI award R01CA207083 (K.C.W.)
Differential Inhibitory effects of Nocodazole on Human Hematopoietic and Hepatocytic cells and Their Stem/Progenitors in Culture
Authors: Baquier Jocelyn , Darrell Henry , Brumaire Sebastien , Schoonover Laura , Hu Tang 
Published: November 2023

Nocodazole is known as a cell cycle inhibitor that inhibits polymerization of microtubules. However, its effect on apoptosis and differentiation of human myeloid leukemia cells and cancerous hepatocytes, especially on their stem/progenitors is largely unknown. In this study, we investigated the effect of Nocodazole on the growth of two human myeloid leukemia cell lines, TF‐1a and MV4‐11 and one liver cancer cell line, HEP‐G2. Addition of Nocodazole at concentrations of 5μM significantly inhibited the growth of MV4‐11, TF‐1a, and HEP‐G2 cells in culture, with 50% (MV4‐11), 45% (HEP‐G2), and 40% (TF‐1a) inhibition being observed, respectively, on day 3 after treatment with Nocodazole. The inhibitions were dose‐dependent with maximal inhibition being observed at a concentration of 10uM of Nocodazole. Less than 1 μM had no significant inhibitory effect on the growth of the cells, measured by XTT proliferation assay after the cells were treated with Nocodazole. Paralleled to the changes in the cell proliferation, expression of cdc2 and cdk2 were also inhibited, indicating that the inhibition was linked to the cell cycle arrest. However, Trypan blue stain and cell morphology analysis suggested that some cells displayed apoptotic‐like cell death in the presence of Nocodazole, which was confirmed by activation of caspase proteins. We were surprised to find that the stem/progenitors of MV4‐11, HEP‐G2 and TF‐1a cells showed a higher sensitivity to Nocodazole treatment measured by counting colony forming cells in semi‐solid (soft agar or soft agar/agarose) culture. At a concentration of 0.01uM, Nocodazole inhibited 80–90% stem/progenitors derived from MV4‐11, HEP and TF‐1a. The Giemsa and methylene blue/eosin stain showed that Nocodazole also induced differentiation in about 30% TF‐1a cells, evidenced by reduced nucleus/cytoplasm ratio. Our data demonstrated that Nocodazole induced‐inhibition of the cells tested is the result of its multiple functions including the cell cycle arrest, apoptosis and differentiation, which are cell type dependent. The high sensitivity of hematopoietic stem/progenitor cells to Nocodazole makes this agent a potential drug for disrupting damaged bone marrow stem cells before receiving healthy bone marrow transplantation.Support or Funding InformationSupported by NIH‐NIGMS RISE Grant, R25 GM059244‐16 Barry University.
Molecular Characterization and Pathogenicity of Meloidogyne incognita on Tomato Cultivars (Solanum lycopersicon L.)
Authors: ABDULAI MUNTALA , Cole Biodun Claudius , Fawole Bamidele 
Published: November 2023

The study was conducted to determine the distribution of the common Meloidogyne species in and around the Ibadan area in Oyo State, south‐west Nigeria, West Africa using Polymerase Chain Reaction (PCR), as well as determine the effect of Meloidogyne incognita on five tomato cultivars. The locations included Akobo 7°25′49.13″N; 3°56′ 55.44″E (a peri‐urban vegetable farm), Ijaye 7°50′48.60″N; 3°34′11.23″E, National Institute for Horticultural Research (NIHORT) 7°24′19.13″N; 3°50′57.01″E, International Institute of Tropical Agriculture(IITA), Ibadan 7°29′52.05″N; 3°54′ 19.16″E and inoculum plots of the Department of Crop Protection and Environmental Biology, University of Ibadan 7°27′4.14″N; 3°53′ 49.19″E. DNA was extracted from the bulk juveniles, according to modified (Dellaporta et al., 1983). Identification of species was carried out using Meloidogyne species universal primer 194/195 and specific SCAR primers MIF/MIR. The nucleic acid was size‐fractioned in 1% agarose gel, stained with 4 μl ethidium bromide and captured by the ultraviolet light. Meloidogyne incognita produced amplification fragments of 720‐bp and 999‐bp for 194/195 and MIF/MIR primers, respectively. Meloidogyne incognita and javanica were the predominant species of root‐knot nematodes identified from the collected samples. The pathogenicity of Meloidogyne incognita was evaluated at different egg mass inoculum levels on five tomato cultivars in the screenhouse in (IITA). All growth parameters such as plant height, leaf number, and yield responded negatively with increasing inoculum levels for all the cultivars except Small Fry VFN and Celebrity cultivars which were found to be resistant based on (Soriano et al., 2000) resistance rating. The results also showed that the Ibadan Local cultivar was the most susceptible to M. incognita. The reproductive factor of the nematode (RF) was determined according to (Oostenbrink, 1966). The root galling index was rated on a 0–5 scale, where 0=0% galled roots; 1= < 10%, 2= 10–25%, 3= 25–50%,4=50–75% and 5= > 75% galled roots (Soriano et al., 2000). All data were analyzed by analysis of variance using SAS 9.2 version and means were separated using Least Significant Difference (LSD). In conclusion, the common meloidogyne species distribution in south‐west Nigeria was determined and this is very important in the formulation of management tactics against this pathogen.Support or Funding InformationThe research was supported by Alliance For A Green Revolution in Africa (AGRA)
Effects of Over‐Expression of RecA on Transformation in Bacillus subtilis
Authors: Penumutchu Swathi , Korry Benjamin , Belenky Peter 
Published: November 2023

Antibiotics are used heavily in modern medical practices and they often affect microorganisms in unanticipated ways. One such effect of antibiotics on bacteria is the transfer of antibiotic resistance. These resistant strains of bacteria pose a threat to current medical practices because their growth cannot be controlled. In the gram‐positive bacteria, Bacillus subtilis, the development of antibiotic resistance occurs through several methods, one being horizontal gene transfer (HGT). Exogenous DNA is taken up by cells, resulting in transformed cells with integrated DNA that confers antibiotic resistance. Transformation in bacteria relies on competence and generates genetic diversity through integrating DNA present in the environment. The SOS response in some bacterial cells is responsible for correcting DNA damage. Genes in the SOS box such as RecA are involved in the processes of homologous recombination and nucleotide excision repair. We hypothesize that the RecA levels increase in response to DNA damage, aiding homologous recombination and transformation in cells. According to preliminary experiments conducted, the addition of antibiotic stress causes an increase in the number of transformed cells and an increase in RecA expression. It is proposed that the over‐expression of RecA will allow cells to better integrate exogenous DNA and increase transformation efficiency levels. This study has significant implications into the understanding of how antibiotics effect various populations of bacteria and the development of pools of genetically diverse bacteria.Support or Funding InformationResearch sponsored by National Science Foundation, Division of Integrative Organismal Systems, IOS‐1249925
Genesis of Antibiotic Resistance XXI Non‐Existent F‐Tag‐428 implementation in developing countries, exacerbate genesis of antibiotic resistance (AR)
Authors: Carbajal Carlos , Fuentes Esai , Wickham Cheyenne , Lopez Christian , Johnson Dennie , Kannan Subburaj 
Published: November 2023

As per the American Society of Consultant Pharmacists (ASCP) mandated guidelines, the F428: Category = Quality of Care, drug regimen review is a prime requirement to avoid prescription drug induced and unforeseen clinical outcomes in patient care. The clinical directive by the ASCP is that the drug regimen of each resident must be reviewed at least once a month by a licensed pharmacist. Surveys and data analysis conducted in developing countries in regard to rural patient care, rehabilitation centers, hospice care, and physicians in private practice concerning the relevance of tag F‐428 and the antibiogram of each patient show that F‐428 is an almost fictitious concept. Prominent pharmacies and pharmacists along the border regions of the United States and Mexico and in developing countries such as India and Nigeria that are strongly influenced by United Kingdom, acknowledge a genuine lack awareness of F‐tag‐428 principles and the necessity for its implementation. The survey data indicates that pharmacists in these developing regions are not part of the clinical decision making process for antibiotic prescription and physicians who are in private practice are not mandated to keep record of antibiotic prescriptions. Information concerning individual culture sensitivity assay results are on file. There do exist prevailing and synergistically compounding factors that make implementation of F‐428 a futile exercise in developing countries. The following factors are considered derogatory to F‐428 implementation; the inappropriate prescription of antibiotics by physicians, poor compliance by patients, the over‐the‐counter availability of antimicrobials as a nonprescription commodity, patient ‐ time pressures, purulent discharge, diagnostic and treatment uncertainties, no availability of a rapid and low cost antibiotics, culture and sensitivity, lack of facilities for conducting antibiogram in rural settings, lack of antibiotic guidelines, inadequacy or absence of regional laboratories to provide periodic and continuing information concerning antibiotic resistance, patient requests and expectations, patient literacy regarding antibiotics (principally women), patient pressure for antibiotics prescriptions for the abatement and expeditious relief from infectious disease, and tenuous pathways for maintaining the continuing medical education requirement for physicians (Medicos with MBBS and M.D.) F428 implementation goals contrasted with the above program frustration, and in consideration of present data analysis irrefutably indicate that antibiotic usage in developing countries poses imminent risk factor for Antibiotic Resistance Pandemic (ARP). Data analysis and adequate literature sources will be presented at EB 2017.Support or Funding InformationProfessional development funds to Subburaj Kannan
Determining the Rhodoquinone Biosynthetic Pathway in Rhodospirillum rubrum Using Gene Knock‐outs
Authors: Martin Amanda , Shepherd Jennifer 
Published: November 2023

Many parasitic helminths require the metabolic cofactor rhodoquinone (RQ) for anaerobic respiration. Inhibition of RQ biosynthesis may shut down the anaerobic respiration pathway and provide a new target for anti‐helminthic drug design. The bacteria Rhodospirillum rubrum (R. rubrum) is a good model organism for RQ biosynthesis because it utilizes the same respiration pathway as the helminths when grown under anaerobic conditions. Previous studies have shown that ubiquinone (Q) is a required precursor to RQ in R. rubrum, and that the gene, rquA, is required for this conversion. Since this process likely requires additional enzymes, further investigation has identified potential gene targets within the R. rubrum genome that may be involved in the pathway. This project involved completing a collection of knockout mutant strains, with the deletion of ten genes from the R. rubrum genome that are hypothesized to be involved in the RQ biosynthetic pathway. RQ production was analyzed using liquid chromatography mass spectroscopy in each of the mutant strains, alongside wild type. The gene expression of rquA was also monitored using real‐time quantitative PCR.Support or Funding InformationNational Institutes of Health (1R15GM096398‐01) and Howard Hughes Medical Institute (award to Gonzaga University).
Increased N‐acetyltaurine in the skeletal muscle after endurance exercise
Authors: Miyazaki Teruo , Nakamura Yuho , Ebina Kei , Ra Song‐Gyu , Ishikura Keisuke , Ohmori Hajime , Ikegami Tadashi , Matsuzaki Yasushi , Honda Akira 
Published: November 2023

AimAcetate produced from acetyl‐CoA in the liver is utilized for energy production in the skeletal muscle after reconversion to acetyl‐CoA during endurance exercise. However, excess acetate in the muscle might become a nuisance that disturbs normalizing of energy metabolism after the exercise. Therefore, it is suggested that acetate may be metabolized to a novel metabolite N‐acetyltaurine (NAT) by reacting with taurine abundantly contained in the muscle for facilitation of urinary acetate excretion. This study aimed to evaluate NAT in serum, urine, and muscle in human and rats after endurance exercise, and in the cultured muscle cell.MethodNAT and taurine levels in serum and urine from healthy volunteers after a transient endurance running and in the soleus muscle from rats after a treadmill running to exhaustion were measured by HPLC‐MS/MS system. The muscular ability of NAT synthesis was also evaluated in C2C12 myotube treated with acetate and taurine.ResultSerum taurine and NAT levels were significantly increased immediately after the exercise, and recovered to the basic levels after one day. Urinary excretions of taurine and NAT were markedly higher in the post 24‐hour period. In the rat muscle, NAT concentration was significantly increased correlated with its level in serum after the exercise. When taurine was co‐treated with acetate to the myotube, the significant inhibition of intracellular acetyl‐CoA accumulation and the significant facilitation of extracellular NAT excretion were observed.ConclusionThese findings suggest that NAT might be synthesized to excrete the excess acetate from the skeletal muscle into the urine after endurance exercise in order to prevent intramuscular excess accumulation of acetyl‐CoA that might induce a metabolic imbalance after the exercise.Support or Funding InformationThis study was supported in part by Kakenhi grants (15K09026, 15K08319, 16K01734) from the Japan Society for the Promotion of Science.