bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proton‐Dependence of the MitoNEET [2Fe‐2S] Cluster : An Electrochemical and Structural Investigation
Authors: Bak Daniel W. , Elliott Sean J. 
Published: June 2021

MitoNEET is a novel 3‐Cys, 1‐His ligated redox active [2Fe‐2S] cluster binding protein, whose biological function remains unclear. MitoNEET is of interest due to its interaction with the anti‐diabetes drug pioglitazone, a member of the TZD drug family, and its unique cluster ligation. Here, a characterization of the clusters unique ligand environment is presented. Using protein film voltammetry, the potential of the mitoNEET cluster is found to be 0 mV at pH 7, where upon binding of pioglitazone reduces the potential to −100 mV. This is one of the first reports of PFV being used to monitor drug binding. Additionally, the mitoNEET cluster demonstrates unusual proton coupled‐electron transfer as well as marked proton‐dependent cluster instability. Through a series of site‐directed mutations of conserved residues around the [2Fe‐2S] cluster, both of these phenomena have been examined, demonstrating the presence of multiple sites of protonation that affect both cluster midpoint potential and cluster stabilization. The high conservation of these residues, which reduce cluster stability, suggest a physiological role for cluster loss and lead to a putative model, in which mitoNEET may sense cellular oxidation state, proton concentration, or iron levels. Changes in MitoNEET cluster binding could potentially mediate either cluster transfer or additional signaling events within the cell.NIH‐NIGMS R01‐GM072663
Akt is required for Rac1 mediated mitochondrial oxidative stress and pulmonary fibrosis
Authors: Casey Jennifer , Murthy Shubha , Ryan Alan J , Carter A. Brent 
Published: June 2021

The production of reactive oxygen species, especially hydrogen peroxide (H2O2) from alveolar macrophages, has been linked to the development of pulmonary fibrosis. We have shown that Rac1 is imported into the mitochondria and modulates H2O2 production in macrophages. In this study upstream regulators of Rac1 mitochondria import were investigated. Rac1 and Akt have been shown to positively and negatively modulate each other. We hypothesized that Akt activity was required for Rac1 activation and mitochondrial import. We found that macrophages exposed to chrysotile asbestos had increased Akt activity. Rac1 mitochondrial import was enhanced by the over‐expression of constitutively active Akt and conversely the knockdown of Akt was shown to abrogate Rac1 mitochondrial translocation, as Rac1 remained in the cytoplasm of macrophages expressing Akt siRNA. In contrast to the cytoplasm, Rac1 activity was significantly upregulated in the mitochondria of macrophages expressing constitutively active Akt, which consequently resulted in increased H2O2 production in these cells. These observations suggest that Akt plays a vital role in the development and progression of pulmonary fibrosis, as it is necessary for mitochondrial Rac1 import and regulating mitochondrial oxidative stress.(Supported by 2R01ES015981–06, R01ES014871, VA Merit Review 1BX001135 (to A.B.C.) and NIH T32 CA078586).
Association of I/D ACE polymorphisms with hormonal status and oxidative stress in Mexican Mestizo women
Authors: Lugo Gabriela , Hernandez‐Caballero Marta , Nicolás‐Franco Ricardo , Ocharan‐Hernández Esther , Jiménez‐Zamarripa Carlos , Calzada‐Frías Jesús , Linarez‐Pérez Luz , Calzada‐Mendoza Claudia 
Published: June 2021

OBJECTIVEAnalyze the association between the presence of I/D ACE variants with hormonal status and oxidative stress in Mexican Mestizo women.METHODSIn this study were included 38 healthy women and divided into two groups (pre‐menopausal or postmenopausal), to which a) menopause was corroborated by clinical evaluation and hormonal profile; b) polymorphisms were identified by real‐time PCR, sense oligonucleotide (5′‐CTG GAG ACC ACT CCC ATC CTT TCT‐3′) and antisense oligonucleotide (5′‐GTG GCC ATC AT ACA TTC GTC AGA‐3′); c) malondialdehyde was identified as a marker of lipid damage oxidative stress.RESULTSThe women included were classified according their estrogenic status (premenopausal or postmenopausal), which was corroborated by medical history and hormonal profile. With respect malondialdehyde and glucose levels we found that were significantly higher in post‐menopausal (Mann‐Whitney U Statistic, p <0.001). However, in each group, oxidative stress and blood glucose were not associated with genotypes.CONCLUSIONSThe I/D ACE genotypes were not associated with damage to lipids or with hyperglycemia observed in postmenopausal but it could participate associated with other risk factors. Before might due to the analyzed women were healthy, right now we are studying the association between I/D ACE genotypes and response to tibolona therapy in hypertenses postmenopausal.
Modulation of Amphiregulin Gene Expression by Estrogen in Breast Cancer Cells
Authors: Luvizon Aline Carbonera , De Sibio Maria Teresa , Conde Sandro Jose , Luvizotto Renata Azevedo Melo , Olimpio Regiane Marques Castro , Moretto Fernanda Cristina Fontes , Fecchio Denise , Nogueira Celia Regina 
Published: June 2021

This study aimed evaluate whether estrogen modulates amphiregulin (AREG) gene expression in breast tumor cells. For this, MCF‐7 cells were treated for 1 or 4 hours with estrogen (E2 10−7 M) in the absence or presence of estrogen receptor inhibitor (ICI 1μM), cyclohexamide (CHX 10μg/ml), actinomycin D (ACTD 5.0 pg/ml) or LY294002 (50μM). Gene expression was assessed using RT‐qPCR, at 5% significance. Estrogen treatment increased AREG gene expression at both moments evaluated. This effect was partially blocked by ICI in MCF‐7 cells, suggesting that a hormone effect requires estrogen receptor (ER). ACTD treatment does not affect the AREG gene expression, demonstrating the independence of mRNA synthesis in the AREG induction in E2‐treated cells treated. Treating cells with CHX significantly decreased gene expression compared to E2 treatment alone, indicating that protein synthesis is necessary for an estrogen effect. Estrogen induced AREG gene expression is partially blocked by LY, showing that the PI3K pathway is required for a portion of this expression. These data demonstrate that estrogen augments AREG gene expression by ER and by PI3K pathway in MCF‐7 breast cancer cells. This effect is dependent on protein synthesis and independent of mRNA synthesis, indicating extranuclear actions at both times evaluated.Supported by: Fapesp and CNPq
Protein Kinase C Isoforms are Expressed During Intestinal Regeneration in Sea Cucumber Holothuria glaberrima.
Authors: Rosado Edwin Antonio , García José E 
Published: June 2021

Molecular and cellular studies on the intestinal regeneration process of the sea cucumber Holothuria glaberrima allows us to understand how cells are rearranged and assembled into a functional organ. Protein kinases c (Pkcs), a superfamily of serine/threonine kinases, have been implicated in a wide range of cellular processes and in the regulation of growth, apoptosis, and differentiation in a variety of cell types. We now report the characterization of at least four Pkc isoforms from regenerating intestine cDNA libraries of H. glaberrima. One of the Pkc isoform showed similarity to the PB1 domain required for the enzymatic activity of atypical Pkcs (identity >; 63%). Another three Pkc isoforms showed the highest similarity to the C1 activation domain of the classical Pkc isoforms (identity >; 46%). Two of the Pkcs, one classical and one atypical isoform, were significantly upregulated in the regenerating intestine from early to middle stages of regeneration (3–14 days post‐evisceration) compared to normal uneviscerated intestine where its expression was almost negligible. The increase in gene expression coincides with drastic dedifferentiation, intense cellular division, and apoptosis events that take place during early to middle stages of regeneration implicating Pkcs as being key modulators of these processes.Research supported by NIH Grant Number 5T34GM007821–33.
Small is beautiful: a practical course in microsurgery for medical students
Authors: Lin Daniel , Lewis Thomas L , Mobley Mark , Burnett Brian , Tunstall Richard , Abrahams Peter 
Published: June 2021

ObjectiveRun a short course in microsurgery for medical students which aims to introduce the practical skills for suturing at a microscopic level and develop interest in specialties which use microsurgery.MethodsA total of 4 microsurgery workshops were run between June 2012 and January 2013 under expert supervision. The workshops lasted 3 hours each and were open to 12 medical students at each session. Delegates were paired to 6 stations with 1 operating microscope and microvascular kit at each station to practice suturing different materials under the microscope and compete in a microsuturing competition to conclude the session. Pre‐ and post‐workshop qualitative questionnaires were completed.ResultsThe total attendance for the 4 workshops was 42 delegates. Progression was demonstrated across all workshops with students becoming more confident at operating surgical microscopes and microsuturing. Feedback showed that teaching microsurgery to medical students requires more time and better equipment. 67% (n=28) of students felt that a good understanding of microsurgery is important for their future career. Students enjoy friendly competition.ConclusionsA structured microsurgical course designed for medical students was conceived and developed with positive outcomes. This novel workshop has potential applications to other aspects of anatomy education.Thanks to Mercian Surgical Instruments.
Iron Bioavailability of Maize Hemoglobin in a Caco‐2 Cell Culture Model
Authors: Beavers Alyssa Whitney , Bodnar Anastasia L , Scott Marvin Paul , Proulx Amy K , Reddy Manju B 
Published: June 2021

Maize is an important staple crop in many parts of the world but has low iron bioavailability, in part due to its high phytate content. Hemoglobin is a form of iron that is highly bioavailable and not affected by phytate. We hypothesize that biofortification of maize with iron can be accomplished by overexpression of maize hemoglobin in the endosperm. Maize was transformed with a gene construct encoding a translational fusion of maize globin and green fluorescent protein under transcriptional control of the maize 27 kDa gamma zein promoter. Iron bioavailability of maize hemoglobin produced in E. coli and transformed seeds expressing the maize globin‐GFP fusion was determined using an in vitro Caco‐2 cell culture model. Maize flour fortified with purified hemoglobin had iron bioavailability similar to flour fortified with ferrous sulfate or bovine hemoglobin but is significantly higher than unfortified flour. Transformed maize was found to have significantly higher iron bioavailability than untransformed seeds, suggesting that overexpression of maize globin in endosperm may be one of the strategies to improve iron bioavailability of maize.Supported by Bailey Career Research Award and Biotechnology fellowship at Iowa State University
Folate intake and status of healthy young females in Serbia, a country without folic acid food fortification
Authors: Ivankovic Marija Djekic , Gurinovic Mirjana , Savikin Katarina , Nikolic Marina , Glibetic Marija 
Published: June 2021

ObjectiveA single‐day cross‐sectional study was performed to assess folate intake and status of healthy young females in Serbia, a country without folic acid food fortification.MethodDietary intake of folate was assessed on the sample of 420 women (aged 18 to 30) using validated semi quantitative food frequency and 24 hr recall questionnaires. Folate intake was calculated using DietAsses nutritional software and Serbian Food Composition Data Base. On 10% of participants’ folate status was determined by red blood cell (RBC) and serum folate concentrations.ResultsMean daily intake of folate was more than 400 μg in 9. 77% of participants and only 0.71% of all participants were taking folic acid supplements. In a subpopulation of 40 female subjects, calculated mean daily intake of folate was 311.84 ± 81.20 μg DFE (dietary folate equivalents). The results of serum and RBC folate indicated that 32.5% of females in Serbia were folate deficiency and only 20% reached RBC folate concentrations needed to prevent fetal neural tube defect (>;400 ng/mL).ConclusionFolate was below the daily recommended intake (400 μg/day) in more than 90% of participants, and prevalence of folate deficiency was high among females of reproductive age. Our data demonstrates that there is a need for promotion of folic acid supplementation among young women in Serbia.Source of research support: Ministry of Science, Serbia III grant 41030
Self‐Reported Dietary Intake and the Human Metabolome
Authors: Guertin K A , Moore S C , Sampson J N , Stolzenberg‐Solomon R Z , Sinha R , Cross A J 
Published: June 2021

Metabolomics may improve upon self‐reported measures of dietary intake, or offer a substitute when self‐report is unavailable. We investigated partial Pearson correlations between self‐reported diet and ~500 serum metabolites, measured by HPLC and GC‐MS, in 254 adults from a large U.S. cohort. After Bonferroni correction and adjustment for age, gender, smoking, and energy intake, >;43 metabolites were correlated with citrus fruits, seafood, peanuts, coffee, alcohol, calcium, or multivitamins. Serum proline betaine, found in citrus fruits, was correlated with citrus intake (r=0.39). As expected, multivitamins were associated with higher serum α‐tocopherol (r=0.31) and lower γ‐tocopherol (r=−0.26). 3‐Carboxy‐ 4‐methyl‐5‐propyl‐2‐furan propionic acid (CMPF), a uremic toxin which induces oxidative stress in vitro and impedes drug metabolism, was associated with fish intake (r=0.32); CMPF is of unknown origin but has been detected in fish. A further 17 unknown metabolites were associated with diet (r=0.23–0.38); identifying these metabolites may provide insight into downstream effects and diet‐disease associations. Future studies should investigate correlations reported herein, associations of these metabolites with disease, and determine whether dietary and metabolite data can be combined to better characterize associations with disease.Funding: NCI Intramural Research, NIH
Hypoxia in pressure overloaded heart
Authors: Nanka Ondrej , Pesevski Zivorad , Stopkova Tereza , Sedmera David 
Published: June 2021

The heart grows in response to circulatory demands and this growth is governed by genetic programs but may be modified by hemodynamic alterations. Hypoxic regions are present in the developing myocardium. Conotruncal banding (CTB) is a well‐established model of embryonic pressure overload. The aim of this study was to elucidate how the extent of hypoxic regions in myocardium is changed under pressure overload.Conotruncal banding was performed in the chick model at embryonic day (ED) 4.The marker for hypoxia Hypoxyprobe 1, was injected into the vitelline vein at ED 6 and ED 8. The embryos were reincubated for 1h and then fixed in 4% PFA. The reaction product was detected on paraffin sections with Hypoxyprobe‐1 antibody.Examination of control hearts showed isolated regions of hypoxia in the left ventricular wall and interventricular septum. In pressure‐overloaded hearts we found ventricular dilatation, thickening of the compact myocardium and trabeculae. The hypoxic regions were significantly more extensive in the compact layer of both ventricles, septum, and the outflow tract.We conclude that the thickening of the embryonic myocardium induced by pressure overload results in its increased hypoxia. This finding can explain previous observations of matching capillary growth in this model, as well as accelerated maturation of the conduction system.Supported by project UNCE 204013 and PRVOUK P35/LF1/5.
A prospective study of dietary omega‐3 fatty acids and the risk of age‐related macular degeneration
Authors: Wu Juan , Cho Eunyoung , Schaumberg Debra A. , Sastry Srinivas M. , Willett Walter C. 
Published: June 2021

MethodFrom 1984 to 2008, we prospectively followed 67,206 women aged ≥ 50 y in the Nurses’ Health Study who had omega‐3 fatty acids intake assessed by a validated food frequency questionnaire and were free of AMD, cancer and cardiovascular disease at baseline.ResultsOver 24 years of follow‐up, we accrued 1,307 AMD cases with 700 early and 607 late AMD. Comparing the highest quintile to the lowest of docosahexaenoic acid intake, the multivariate‐adjusted hazard ratios (HR) for total, early and late AMD were 0.81 (95% confidence interval, 0.66, 0.99), 0.64 (0.48, 0.84; p for trend, 0.003), and 1.08 (0.80, 1.46), respectively. The results were similar for eicosapentaenoic acid. For alpha‐linolenic acid, the corresponding HRs were 1.26 (1.02, 1.57), 1.36 (1.02, 1.83; p for trend, 0.02) and 1.16 (0.84, 1.59). Compared with women who consumed seafood <1 serving/m, women who consumed ≥5 servings/wk had a HR of 0.50 (0.29, 0.87; p for trend, 0.004) for early AMD. The inverse associations between docosahexaenoic acid and total and early AMD were more evident in women <70 years old and those who took ≥1 tablet of aspirin/wk.ConclusionBoth docosahexaenoic acid and eicosapentaenoic acid were associated with decreased risk of early AMD but not late AMD. Alpha‐linolenic acid was associated with increased risk of early AMD and warrants further investigation. Higher intake of seafood may benefit primary prevention of AMD.
Programmed cell death in hyperplasic ovaries of ex‐fissiparous planarian Dugesia arabica
Authors: Harrath Abdul Halim , Ahmed Mukhtar , Mansour Lamjed , Alwasel Saleh 
Published: June 2021

Planarians can reproduce exclusively sexually or/and asexually by fissiparity. Among fissiparous populations individuals can sexualize and develop ovaries of remarkable size called hyperplasic ovaries (Gremigni and Banchetti, 1972). Nevertheless, it has been reported that individuals that become sexual are usually sterile because they usually lay infertile cocoons (Grasso and Beanzzi, 1973).The aim of this study is to demonstrate, through ultrastructural and TdT‐mediated dUTP nick end‐labeling (TUNEL assay) in intact sections of hyperplasic ovaries the cause of infertility of ex‐fissiparous planarians. Our study has been carried out on Dugesia arabica collected from Yemen (Harrath et al., 2013) that reproduce asexually in the field. After having been kept for few months in the laboratory, some of the specimens had been sexualized.Ultratsructural and TUNEL assay investigations demonstrate that oogonia and young oocytes still develop normally compared to previous studies describing oogenesis in other Dugesia species. At the later stage, very few fertile oocytes of a hyperplasic ovary may succeed in completing their growth whereas the majority at the diplotene stage undergoes a progressive degeneration through programmed cell death. The latter leads to the self‐destruction of oocytes and may represent the most important cause of infertility of ex‐fissiparous planarians. This process should be correlated with polyploidization or genomic variations.
New anti‐inflammatory benefits of antibiotics: Tulathromycin promotes apoptosis and efferocytosis, and inhibits pro‐inflammatory CXCL8 production in a model of porcine pleuropneumonia
Authors: Duquette Stephanie , Fischer Carrie D , Muench Gregory P , Lucas Merlyn J , Buret Andre G 
Published: June 2021

Neutrophil (PMN) apoptosis and subsequent clearance by surrounding macrophages (MΦ; efferocytosis) is critical to the resolution of inflammation following infection. Abnormal resolution of inflammation is responsible for the severe tissue damage characteristic of pneumonia, as in Actinobacillus pleuropneumoniae porcine pleuropneumonia. The superior clinical efficacy of some antibiotics has been attributed to inherent anti‐inflammatory properties via mechanisms that remain obscure.Objectiveto characterize anti‐inflammatory properties of tulathromycin (TUL) in a model of porcine pleuropneumonia.ResultsIn vivo and in vitro, TUL induced porcine PMN apoptosis in a time‐and dose‐dependent manner, as determined by cell death ELISA, TUNEL fluorescent staining, and cleavage (activation) of caspase‐3, detected by western blot. TUL‐treated apoptotic PMN were readily efferocytosed by MΦ. TUL also induced delayed apoptosis and inhibited pro‐inflammatory CXCL8 production in porcine MΦ.ConclusionTUL's superior clinical efficacy may be due in part to anti‐inflammatory benefits mediated by PMN apoptosis and inhibition of CXCL8 in MΦ, which together promote the resolution of inflammation. Supported by Pfizer.
Exosomal microRNA modulates pathways of liver fibrosis by regulating connective tissue growth factor (CTGF) expression in fibrogenic cells during chronic injury.
Authors: Chen Li , Brigstock David 
Published: June 2021

AimTo establish the regulation of Connective Tissue Growth Factor (CTGF) expression in hepatic stellate cells (HSC) by delivery of miR‐214 in exosomes.MethodsExosomes isolated from conditioned medium of mouse HSC were characterized by Western blot, dynamic light scattering, zeta potential analysis, and cryo‐TEM. MiR‐214 was detected by RT‐PCR. Donor HSC were treated with GW4869 to inhibit exosome production and recipient HSC were transfected with a luciferase reporter vector under the control of a wild type CTGF 3′‐UTR or a mutant CTGF 3′‐UTR lacking the miR‐214 binding site.ResultsHSC exosomes were bi‐membrane vesicles, 80–150nm in diameter, negatively charged (−26mV), and positive for CD9. MiR‐ 214 was present in exosomes and its levels were increased by transfection of HSC with pre‐mir‐214. MiR‐214 levels in exosomes but not in cell lysates were reduced by pre‐treatment of the cells with GW4869. Co‐culture of miR214‐transfected donor HSC with CTGF UTR luciferase reporter‐transfected recipient HSC resulted in miR‐214‐dependent and GW4869‐dependent regulation of activity of the wild type, but not mutated, CTGF 3′‐UTR. CTGF 3‐UTR activity in activated recipient HSC was more greatly inhibited in a GW4869‐dependent manner by co‐culture with freshly isolated donor HSC (high endogenous miR‐214 levels) than with highly activated donor HSC (low endogenous miR‐214 levels).ConclusionsMiR‐214 is exported exosomally between neighboring HSC, suppressing CTGF production by the cells, After injury, miR‐214 expression is suppressed, resulting in its reduced exosomal delivery and increased CTGF expression in recipient cells. Exosome‐dependent delivery of miRs between neighboring HSC represents a novel mechanism by which fibrotic pathways are regulated during chronic liver injury.
Colorectal cancer cell lines made resistant to SN38‐and Oxaliplatin: Roles of altered ion transporter function in resistance?
Authors: Christensen Sandra , Jensen Niels Frank , Stoeckel Johanne Danmark , Belling Kirstine C , Romer Maria Unni , Gupta Ramneek , Brünner Nils , Pedersen Stine Falsig , Stenvang Jan 
Published: June 2021

Colorectal cancer (CRC) is the 3rd most common cancer globally, with 5year survival rates of ~50%. Response rates to standard treatments (irinotecan (SN38) or Oxaliplatin (Oxp)) are 31–56% and drug resistance is a major problem. Thus, we established in vitro CRC models to investigate SN38 and Oxp resistance in HCT‐116, HT‐29 and LoVo cells. Microarray analysis and qPCR validation showed that mRNA expression of glutamate transporters SLC1A1 and SLC1A3 were markedly altered in resistant cells. Remarkably, mRNA levels of SLC1A3 were increased by ~40‐and ~2500‐fold in SN38‐and Oxp‐resistant HT29 cells, respectively. Studies are ongoing to assess glutamate uptake in parental and resistant CRC cells and the effect of inhibition/knockdown of SLC1A1 and ‐3 on SN38‐ and Oxp resistance.In conclusion, SN38‐and Oxp‐resistance in CRC cells is associated with SLC1A1 and ‐3 dysregulation. As these transporters have not previously been implicated in SN38 or Oxp resistance and are generally restricted to the CNS, they are potential novel biomarkers for resistance and interesting candidates for therapeutic targeting.Funding: Danish Research Council, Danish Council for Strategic Research, Danish Cancer Society