bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intrathecal antibody production in the Theiler's murine encephalomyelitis model of multiple sclerosis
Authors: Pachner Andrew Rudolf , Brady Jennifer , Narayan Kavitha 
Published: June 2021

Objective: To assess the role of intrathecal antibody production (ITAbP) in a murine model of multiple sclerosis(MS).Background: ITAbP is a hallmark of MS, but is poorly understood. Infection of mice with Theiler's murine encephalomyelitis virus (TMEV) results in a progressive disabling demyelinating disease resembling MS, but the role of antibody in central nervous system(CNS) injury in this model is unknown.Design/Methods: ITAbP in TMEV‐induced demyelinating disease(TMEV‐IDD) was measured using ELISpot for IgG‐producing cells and RT‐PCR for IgG1 mRNA, viral load was determined by RT‐PCR for TMEV RNA, and CNS injury was measured by Rotarod analysis of infected mice. Demyelination and immunoglobulin deposition were assayed histologically in the spinal cord by luxol fast blue and immunofluorescent staining, respectively.Results‐Robust ITAbP was present in 85% of infected mice and correlated positively with CNS injury and viral load. Demyelination and immunoglobulin deposition in injured tissue was prominent in mice with ITAbP.Conclusions/Relevance: ITAbP and immunoglobin deposition is highly associated with CNS injury in a murine viral model of MS. These data provide evidence that intrathecally produced antibody may contribute to CNS injury.
CD4+CD25+FoxP3+ T Regulatory Cells Play a Critical Role in Tolerance to Pancreatic Islets Engineered to Display on Their Surface an Exogenous FasL Protein
Authors: Yolcu Esma S. , Zhao Hong , Bandura‐Morgan Laura , Lacelle Chantale , Askenasy Nadir , Shirwan Haval 
Published: June 2021

Objective: We have shown that islets engineered to display on their surface a chimeric form of FasL with streptavidin (SA‐FasL) induce robust localized tolerance when transplanted into allogeneic recipients. The objective of this study was to elucidate mechanisms of tolerance in this model.Methods: RIP‐OVA BALB/c islets were engineered by cell surface modification with biotin followed by the display of chimeric SA‐FasL. SA‐FasL‐engineered islets were transplanted into streptozotocin diabetic C57BL/6 mice under transient cover of rapamycin. Graft recipients were adoptively transferred with OT‐I TCR transgenic T cells and analyzed for donor‐specific proliferation, clonal deletion, and increased frequencies of T regulatory cells (Treg).Results: Long‐term recipients generated a normal proliferative and cytokine response to donor antigens, demonstrating lack of systemic tolerance. Graft acceptance involved clonal deletion of alloreactive T cells within the kidney draining lymph nodes early post‐transplantation. Although analysis of CD4+CD25+FoxP3+ Treg cells did not revealed their increased frequency in the periphery as compared with rejecting controls, in vivo depletion of Treg cells using an antibody to CD25 early or late post‐transplantation resulted in prompt rejection of tolerated grafts.Conclusion: Tolerance to SA‐FasL‐engineered islets is localized to the graft and involves clonal deletion of alloreactive T cells early post‐transplantation followed by generation/induction of Treg cells that maintain tolerance. NIH (R21 DK61333, R01 AI47864, R21 AI057903, R21 HL080108), JDRF (1‐2001‐328), and ADA (1‐05‐JF‐56).
Donor‐specific memory CD4 T cells provide help for alloantibody production in the absence of CD40/CD154 interactions and germinal center formation
Authors: Rabant Marion , Gorbacheva Victoria , Zhang Qi‐Wei , Kolkin Mark , Valujskikh Anna 
Published: June 2021

CD40 signaling is essential for immunoglobulin class switching in response to T‐dependent antigens. We investigated whether memory CD4 T cell help can be delivered in the absence of CD40/CD154 interactions.We used either polyclonal alloreactive memory CD4 T cells from C57BL/6 (B6, H‐2b) recipients of C3H (H‐2k) skin allografts or TCR transgenic Mar memory CD4 T cells reactive to male HYDby peptide. Wild type B6 or CD40−/− female mice injected with naïve or memory CD4 T cells received heterotopic heart transplants from male C3H donors, donor‐reactive serum alloAb titers were determined by flow cytometry.We observed that memory but not naïve CD4 T cells induced high titers of donor‐specific IgG Ab in wild type B6 recipients treated with anti‐CD154 mAb MR1. After adoptive transfer into CD40−/− mice, memory, but not naïve CD4 cells provided help to CD40−/− B cells to produce donor‐reactive IgG1, IgG2a, IgG2b and IgG3 as early as 1 week post transplant. Despite high titers of serum IgG, PNA and B220 staining revealed no germinal center formation in the spleens of CD40−/− recipients containing memory CD4 T cells. AlloAb production was not affected by the treatment of CD40−/− recipients with MR1 Ab or anti‐ICOS mAb, indicating that the memory CD4 T cell help to CD40−/− B cells was independent of CD154 engagement by an alternative ligand or ICOS/B7RP‐1 pathway.In summary, donor‐specific memory CD4 T cells can initiate alloAb response in CD40‐deficient heart allograft recipients. Thus, therapeutic interruption of CD40/CD154 signaling may fail to efficiently block de novo alloantibody production in T cell sensitized transplant patients.
Impact of pyridoxine (B6) deficiency on serine kinetics in the pig
Authors: House James D. , Zhang Zhenbin , Nitschmann Evan , Wykes Linda J. 
Published: June 2021

The water‐soluble vitamin B6 serves a cofactor for serine hydroxymethyltransferase (SHMT), an enzyme critical to cellular one carbon flow. The current experiment was designed to test the alternate hypothesis that B6 deficiency in an animal model will reduce SHMT activity and serine flux, as measured by stable isotopic dilution protocols. Pigs (commercial genotype; initial wt = 4.7 kg; n=6/treatment) were offered a basal semi‐purified diet (20.5% casein; 3474 kcal ME/kg) containing either 0 (B6−) or 3 (B6+) mg/kg pyridoxine·HCl for a 3 week feeding period, using a pair‐feeding design. At the end of the depletion period, a 6 hr primed (90 μmole/kg)‐constant (90 μmole/kg/h) infusion of L‐[2,3,3‐2H3] serine was administered via indwelling jugular vein catheter. Blood samples (femoral vein catheter) were collected at −60, 0, 60, 120, 180, 240, 300 and 360 min. Tissues were harvested at termination and samples processed for plasma serine m+3 enrichment (GC‐MS), plasma pyridoxal‐5‐phosphate (PLP; radioimmunoassay), and liver SHMT activity. Different superscripts indicate significant differences (P<0.05) by ANOVA F‐test.The current data allow us to accept the alternate hypothesis of a reduction in SHMT activity induced by dietary pyridoxine deficiency, with a concomitant reduction in serine flux. This reduction in serine flux may have implications for overall one‐carbon metabolism, including pathways linked to folate and sulfur amino acid metabolism. Support: Natural Sciences and Engineering Research Council of Canada (NSERC)
Does measurement define hunger, or does hunger define measurement?
Authors: Radimer Kathy 
Published: June 2021

Hunger was “discovered” in the US in the 1960s, the 1980s, and again in the 2000s, but definitions and measurement have varied over time, to include physical and biochemical measures, dietary intake, food‐related behaviors, psychological conditions, and physical sensations. In the 1960s, assessment particularly focused on anthropometry and clinical symptoms, generally undertaken by medical professionals. In the 1980s, community groups tracked food pantry and soup kitchen usage and user characteristics, noting the coincidence with food stamp receipt cycles. Several efforts to develop a hunger measure were undertaken.In the mid‐1990s, the US government held a conference to develop a U.S. measure of hunger and related conditions, bringing together previous work. Hunger was subsumed into the broader framework of “food insecurity” as the most severe category of food security, “food insecure with hunger.” In 2004–06 the Committee on National Statistics (of the National Academies) undertook a review of the US food security survey module and the measurement and reporting methods. It recommended that the word “hunger” not be used as a food security category label, because hunger is a physiological condition, not an economic or social condition. Measurement and language are inextricably entwined in the assessment and depiction of hunger in America.
Within‐individual and within‐group correspondence of creatinine‐normalized urinary biomarkers of in vivo oxidation: TBARS and 8‐OHdG
Authors: Orozco Monica N , Solomons Noel W. , Schuemann Klaus , Friel James K. 
Published: June 2021

Background:Urinary biomarkers, such as TBARS or 8‐hydroxy‐d‐guanosine (8‐OHdG), are used in assessment of severe, clinical oxidative stress, but little is known about their diagnostic value within the presumptive normative range.Objective:To assess the association between 2 urinary biomarkers of in vivo oxidation (TBARS and 8‐OHdG) in subjects undergoing a supplemental iron‐induced oxidation challenge.Methods:Five adult males received two 7‐d courses of: A=120 mg Fe (FeSO4) and B=120 mg Fe + 5 mL vegetable oil. Creatinine‐normalized, urinary TBARS and 8‐OHdG concentrations were quantified in 22 samples from baseline, active supplementation, and washout phases.Results:A significant within‐individual correlation between the urinary biomarkers was observed (Spearman r=0.465, p<0.01, n=110); kappa coefficients for the correspondence of tandem interval increments or decrements of the biomarkers concentrations ranged from 0.24 – 0.81 at individuals’ and group levels, with 4 of 6 between 0.40–0.81 (fair to very good).Conclusions:Within the normative range, we find intriguing within‐individual and within‐group correspondence between the two urinary biomarkers of in vivo oxidation.Sponsored in part by the Malaysian Palm Oil Board and INF‐EMF.
Hemoglobin concentrations are inversely associated with erythrocyte folate concentrations in Colombian schoolchildren, especially among children with low vitamin B12 status
Authors: Arsenault Joanne E. , Mora‐Plazas Mercedes , Forero Yibby , Lopez‐Arana Sandra , Baylin Ana , Villamor Eduardo 
Published: June 2021

The 2005 National Nutrition Survey of Colombia reported that 38% of schoolchildren were anemic, yet the rate of iron deficiency was 3.6%. To determine if other micronutrients may be responsible for anemia, we examined hemoglobin (Hb) concentrations in relation to serum ferritin, vitamin B12, and vitamin A, and erythrocyte folate (eFol) in 2812 children (5–12 y) from Bogota, Colombia. Mean Hb concentration was 145 (SD, 12) g/L; 4% of children were anemic (Hb <127 g/L) while 3% had low ferritin (<15 μg/L). In multivariate analysis, Hb increased with child's age, mother's age, household's socioeconomic stratum, and family income. Low ferritin was related to 3.6 g/L lower Hb (95%CI=−6.0, −1.3). There was an inverse trend in Hb by quartiles of eFol; the adjusted Hb difference between the highest and lowest eFol quartiles was −6.0 g/L (95%CI=−7.2, −4.9, p for trend <0.0001). This difference was greatest among children with B12 <148 pmol/L (−9.6 g/L), followed by children with B12 148–221 pmol/L (−8.0 g/L), and smallest in children with B12 >221 pmol/L (−5.6 g/L); p for interaction = 0.04. The impact of improving vitamin B12 status on this unexpected inverse relation between folate and hemoglobin should be examined in populations where foodstuffs are fortified with folate alone.Funding: Harvard DRCLAS, Bogota's Secretary of Education, Colombian National Institute of Health, National University of Colombia
The effects of chromium (VI) and vitamin C on the frequency of micronucleated erythrocytes in Hybro chicken
Authors: Bajraktari Ismet Dervish , Halili Fetah Murtez , Gashi Agim Maliq , Maxhuni Mirjeta , Bislimi Kemajl , Fetahu Shukri 
Published: June 2021

Chromium (VI) is a genotoxic metal which is rapidly reduced to chromium III by cellular enzymes. During the reduction to the less‐toxic trivalent form, chromium can react with macromolecules including DNA and cause lesions.In this investigation, the evaluation of the genotoxic effects of chromium (VI) on the peripheral blood erythrocytes of Hybro chicken has been carried out. The effect of vitamin C on the genotoxicity caused by chromium (VI) has also been investigated. Chickens were divided into 5 groups (I–V) of 7 individuals each and orally administered varying concentrations of Cr (VI) and vitamin C for four months. Our results show that four months ingestion of two different concentrations of chromium (VI) as well as chromium (VI) + vitamin C resulted in a significant increase in micronucleated erythrocytes. No protective effect of vitamin C in the concentrations applied was observed. Based on our data we confirm that Hybro chicken could be used as an alternative test for the evaluation of the genotoxic effects of environmental contaminants.
Proteomic Analysis of the HCV Encoded Peptide NS5 A Cellular Protein Complex
Authors: French Samuel Wheeler , Gonzalez Oscar , Raychaudhuri Santanu , Fontanes Vanessa , Loo Rachel , Loo Joseph , Dasgupta Asim 
Published: June 2021

Background: Hepatocellular carcinoma (HCC) is the third most common cause of cancer related death worldwide. One of most common causes of HCC includes infection with hepatitis C virus (HCV) in association with cirrhosis. The HCV protein NS5A is required for viral replication and has been implicated in the development of HCC through alteration of cell signaling. The oncogenic potential of NS5A and its impact on cell signaling renders it a reasonable target for therapeutic intervention.Aim: To develop a system to determine cellular signaling pathways altered by the HCV protein NS5A through identification of proteins it form complexes with in cellular extracts.Methods: NS5A protein complexes were purified from stable cell lines expressing NS5AFlag fusion protein, resolved by SDS‐PAGE and silver stained.Results: Complex purification was optimized and at least two proteins (approximately 40 and 70 kDa) were identified as potential NS5A associated proteins.Conclusions: We have identified 40 kDa and 70 kDa cellular protein members of the NS5A complex that may play a role in viral replication or augment the NS5A antiviral response mediated through PKR. Pharmacologic inhibition of these interactions may reduce viral replication and ultimately prevent hepatocellular carcinoma.Supported by: Stein/Oppenheimer Endowment Award, CURE Pilot and Feasibility Study, CURE Named New Investigator Award
CNS Metastasis Model for HER2 Positive Human Breast Cancers
Authors: Strom David K. , Filippelli Crystal S. , Andres Dale , James Mollie M. 
Published: June 2021

Over‐expression of the HER2 oncogene is seen in 20% of all breast cancers. In this population of women, 30% will present with CNS metastasis following the initial diagnosis, and 50% of these women will die of progressive CNS disease. Treatment options are limited and patients’ quality of life is usually compromised.Our laboratory has developed a model of CNS metastasis of a human HER2 positive breast cancer cell line which can be used to evaluate new therapies. We have found that a left ventricular, percutaneous injection of 1×106 cells into athymic rats causes detectable CNS metastases by 4 weeks in 80–90% of subjects. We are using this model to develop novel strategies for blocking CNS metastasis and treating CNS metastasis once it occurs.
Role of neurokinin‐1 receptor during the transition of inflammation to dysplasia in a colitis‐associated colon cancer model
Authors: Pagan Beatriz , Isidro Angel A , Rivera Edelmarie , Coppola Domenico , Wu Jie , Appleyard Caroline B 
Published: June 2021

Long‐standing colitis markedly increases the risk of developing colorectal cancer. Neurokinin‐1 receptors (NK‐1R) have been shown to be involved in chronic colonic inflammation but their role in the transition to dysplasia is unclear.AimTo investigate the role of NK‐1R in a novel model of colitis‐associated dysplasia.MethodsSprague Dawley rats received trinitrobenzene sulfonic acid (TNBS; 30 mg in 50% ethanol ic), followed six weeks later by reactivation with TNBS (5 mg/kg iv) for three days. To induce colitis‐associated dysplasia the rats then received TNBS (iv) twice a week for ten weeks. One group received the NK‐1R antagonist SR140333 (1 mg/kg ip) twice a week for ten weeks; the rest received vehicle. After sacrifice the colons were removed and analyzed for total macroscopic damage, histological analysis, and real‐time RT‐PCR.ResultsPathological analysis revealed a decreased incidence of dysplasia in animals treated with the NK‐1R antagonist compared with the vehicle treated group. Animals receiving SR140333 had significantly less macroscopic and microscopic damage, and a down‐regulation of mRNA levels for EGFR and NK‐1R, which correlated with the pathology.ConclusionOur results suggest that a selective NK‐1R antagonist can delay the development of damage and dysplasia in a novel model of colitis‐associated dysplasia, offering its potential therapeutic use. 1U56 CA126379‐01 & 1F31 GM078951.
The impact of IL‐1 deficiency in colitis‐mediated colon cancer
Authors: Stillie RoseMarie , Shukkur Farooq M , Stadnyk Andrew W 
Published: June 2021

Inflammatory bowel diseases (IBD) predispose individuals to colon cancer. IL‐1, elevated during IBD, is implicated in cancer development in several models. Our objective was to determine the contribution of IL‐1 to carcinogenesis in a mouse model of colitis‐mediated colon cancer. Wildtype (WT), IL‐1R1−/− and caspase‐1−/−mice (n=6–12) were treated with azoxymethane (10 mg/kg) followed by 3 cycles of 3% dextran sulphate sodium. Unlike WT, IL‐1R1−/− and caspase‐1−/− mice had significant mortality (40–50%) after the second and third cycles, although inflammation severity in the mid‐colon did not differ between strains. All strains showed non‐invasive colon carcinoma. Cancer incidence did not differ significantly between strains (WT 60%, IL‐1R1−/− 100% and caspase‐1−/− 100%), however IL‐1R1−/− mice had a higher tumor multiplicity compared to WT and caspase‐1−/− mice (p<0.05). In conclusion, IL‐1R1−/−and caspase‐1−/− mice are more susceptible to chronic inflammation, despite histological inflammation scores that are similar to WT. Although cancer incidence did not differ between strains, the higher tumor number in IL‐1R1−/− mice suggests a protective role for IL‐1 in this model.Funded by Crohn's and Colitis Foundation of Canada
ASK FOR WOMEN'S OPINION FIRST
Authors: Markovic Nenad , Markovic Olivera 
Published: June 2021

INTRODUCTIONIn 2006, the FDA approved a “new vaccine for prevention of cervical cancer and other diseases in females caused by human papilloma virus.” The news raised hopes for eradication of cervical cancer. Professionals recommended new strategies. Only few voices called for caution against over‐enthusiasm and change of Pap test screening. The authors of this abstract have been involved in the improvement of cervical cancer screening and presented their results on several EB meetings in the past.MATERIAL & METHODS: One of the objectives within the mission of the Global Academy for Women's Health is to help women making educated decision on issues of their health. In 2006 and 2007, we evaluated most of the published literature on the cervical cancer prevention strategies, and conducted a limited survey among women at risk to learn more what they think about Pap test.RESULTS: In the US, approximately 1 out of 2,000 women infected with HPV virus developed invasive cervical cancer, but almost all cervical cancers (10,000 /year) were infected with HPV (‘oncogenic’ and other subtypes). These numbers suggest a symbiotic rather than a causal association; HPV infecting the susceptible cancer and promoting its growth thereafter. The survey showed that 99% women were aware of Pap test, but only 70% participated (regularly or irregularly). The reasons for avoiding the test were cited as “uncomfortable” and “waiting for the results is stressful.” However, 93% would participate if an accurate and more convenient home test is available.CONCLUSION: HPV vaccination is justified but its marketing strategy needs a more realistic approach. A home test added to HPV vaccination could be the future strategy that will embrace all women at risk.
Extracellular regulatory kinase (ERK1/2) regulates 15‐lipoxygenase Expression in Primary Human Monocytes
Authors: Bhattacharjee Ashish , Pal Srabani , Feldman Gerald M , Cathcart Martha K 
Published: June 2021

Interleukin‐13 (IL‐13) induces the expression of the lipid‐oxidizing enzyme 15‐lipoxygenase (15‐LO) in primary human monocytes. 15‐LO catalyzes the oxygenation of certain polyunsaturated fatty acids to their corresponding hydroperoxy derivatives, which play an important role in the pathogenesis of atherosclerosis and inflammation. Previously we identified the functional IL‐13 receptor components, the association of Jaks and the activation of Stats. We have also observed the involvement of a cytosolic signaling complex containing Stat3, p38MAPK and PKCδ, in regulating 15‐LO. Our recent data demonstrate that ERK1/2, another MAP kinase, is involved in regulating IL‐13‐stimulated 15‐LO expression in monocytes. IL‐13 induces the activation of ERK1/2 in a time‐dependent manner. Our results show that the ERK1/2 pharmacological inhibitors block both IL‐13 induction of 15‐LO mRNA as well as protein expression. We further demonstrate that ERK1/2 is present in the signaling complex along with p38MAPK, and PKCδ and that ERK1/2 activity has no role in regulating this complex formation. Further investigations revealed that the PKCδ, p38 MAPK and ERK1/2 pathways are independent, parallel pathways, but are indispensable for 15‐LO expression. Our current studies are focused on exploring the mechanisms by which ERK1/2 regulates the gene expression of 15‐LO, an important regulator of inflammation and apoptosis.(This work was funded by HL51068)
Analysis of direct binding of small molecules to G protein βγ subunits: biophysical analysis and binding site mapping
Authors: Seneviratne Pramodh , Wedekind Joseph , Smrcka Alan V 
Published: June 2021

Guanine nucleotide exchange proteins (G proteins) are heterotrimeric proteins composed of three subunits α, β, γ that initiate intracellular signaling cascades. Previously our laboratory identified small molecules that bind to a protein‐protein interaction “hot spot” to achieve selective modulation of downstream effectors. The central hypothesis of the study is that different compounds bind directly to different sub‐surfaces of the Gβγ ‘hot spot’. To assess binding of compounds directly to Gβγ we developed a Surface Plasmon Resonance (SPR) method utilizing immobilized Gβγ subunits. The results indicate that multiple compounds bind directly to Gβγ with affinities in the range of 400 nM to 10 μM. The binding is reversible, but with surprisingly slow on and off rate kinetics. For example: the Kd for binding of gallein to Gβ1γ2 was 420 nM with kon=1 × 103 M−1s−1, koff= 4 × 10−4 s−1. We have separately purified Gβγ subunits with single amino acids within the Gβγ hotspot mutated to alanine, and are assessing small molecule binding by SPR. We also obtained co‐crystals of several small molecules bound to Gβγ that diffract to 2.6 Å and are in the process of solving their three dimensional structures using x‐ray crystallography. Understanding how selective small molecules interact with Gβγ will be important for determining the mechanism of action of these compounds and developing more potent and selective agents.This work was funded by National Institutes of Health GM 060286