bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D Printing and the Organ Crisis
Authors: Cevallos Manuel , Butler Jessica , Stabile Diana 
Published: April 2020

According to the United Network for Organ Sharing (UNOS) published in January 2019, there are 124,206 men, women, and children currently in need of a lifesaving organ. With barely 26,448 transplants performed annually and only 12,740 people registered as donors, this, unfortunately, equates to 8,000 individuals dying per year in the United States alone. Nevertheless, can advances in bio‐engineering alleviate this upward trending crisis?Researchers utilizing three‐dimensional (3D) bio‐printing are currently able to mimic the structure of natural tissues. Recently published in The Journal of Thoracic and Cardiovascular Surgery (2016), Lei Wand et al. reported successful 3D‐printed titanium ribs implanted into a patient following an extensive lung cancer resection. Further research is being conducted regarding more complex tissues on animal models to test the viability of the 3D printed tissues before implanting into human patients. In 2019, Jae‐Hyun Park et al. published in Science Reported, a 3D‐bioprinted artificial trachea with autologous epithelial cells and chondrocytes in rabbits are feasible. 3D printing has successfully been used for skin grafts, tracheal splints, artificial ears, knee meniscus, corneas, and bone, but not complex organs.Though challenging to replicate synthetically, researchers are still working on angiogenesis as one of significant limitation in the process of transplantation. This presentation reviews the current status of 3D printed organ replication for life‐saving transplants.3D‐Bioprinting OrgansFigure 1
Role of the Epithelial Glycocalyx in Maintaining the Alveolar‐Capillary Barrier During Acute Lung Injury
Authors: Putz Nathan D. , Habegger Luke E. , Shaver Ciara M. , Ware Lorraine B. , Schmidt Eric P. , Bastarache Julie A. 
Published: April 2020

RationaleDisruption of the alveolar‐capillary barrier is a signature feature of acute lung injury. Previous studies have shown the importance of the glycocalyx in maintaining the integrity and homeostasis of the lung endothelium during acute lung injury. However, the role of the glycocalyx on lung epithelial barriers during acute lung injury has not been fully explored. We hypothesize that the lung epithelial glycocalyx is important in maintaining lung epithelial tight junctions in the setting of acute lung injury.MethodsCultured mouse lung epithelial cells (MLE12) were treated with functional or heat‐inactivated heparinase I/III. Additionally, some MLE12 cells were treated with LPS after pretreatment with functional heparinase I/III. Glycocalyx shedding was measured by immunohistochemistry for heparan sulfate (HS). To assess paracellular permeability, electrical cell‐impedance sensing (ECIS) was used to measure the resistance across the epithelial monolayer. To determine whether loss of the glycocalyx affects epithelial tight junctions we measured gene and protein expression of ZO‐1, by PCR, western blot, and immunofluorescence.ResultsMLE12 cells in culture express a robust glycocalyx that is completely shed following treatment with active heparinase I/III at 24 hours. Active heparinase I/III did not cause significant change in monolayer resistance from baseline compared to inactive heparinase I/III by ECIS (Active −142±39.2 v Inactive −118.9±57.9 ohms, p=0.75). Active heparinase I/III did not decrease protein expression of ZO‐1 compared to inactive heparinase I/III (Active
1.55±0.33 v Inactive 1.8±0.25 fold change ZO‐1/Actin, p=0.61). MLE12 cells treated with activated heparinase I/III and LPS had a significantly greater decrease in resistance from baseline compared to inactive heparinase and LPS (Figure
, Active + LPS −145±8.8 vs Inactive + LPS − 7.7±10.8 ohms, p=0.0022)ConclusionTreating MLE12 cells with functional heparinase I/III degrades the epithelial glycocalyx. Loss of the glycocalyx alone was not sufficient to cause permeability defects nor alter the expression of tight junction proteins. However, glycocalyx shedding did increase the susceptibility of MLE12 cells to LPS‐induced injury. In clinical situations, the shedding of the glycocalyx in ALI is often accompanied by compounding factors such as infection, inflammation, or mechanical stress. The current findings suggest that damage to the epithelial glycocalyx may play a key role in maintaining the alveolar epithelial barrier in acute lung injury.Support or Funding InformationSupported by a research grant from Department of DefenseMLE12 cells treated with active heparinase + LPS had a significantly greater decrease in resistance compared to baseline than cells treated with inactive heparinase + LPS p=0.0022.Figure 1
Activated Retinal Microglia Secrete Exosomes Containing Galectin‐3
Authors: Eom Annette Yunsung , Bondarenko Vladimir , Roque Rouel S 
Published: April 2020

PurposeNumerous reports support a potential role for activated microglial cells in the mechanisms of degenerative retinal and brain diseases. Although the exact mechanism remains unknown, our study and those of others describe the transport and release of cytotoxic substances by activated microglia during the initial stages of neuronal cell death. Among these substances, galectin‐3 has emerged as an important player in inflammatory conditions and neurodegenerative diseases by mediating and/or modulating microglial activation. Galectin‐3, a member of an evolutionary conserved family of carbohydrate‐binding lectins, lacks a signal peptide and is most likely secreted via a non‐classical exocytic pathway involving extracellular vesicles (exosomes and microparticles).MethodsTo investigate the role of galectin‐3‐derived retinal microglia in degenerative retinal diseases, activated microglia were isolated from 4–5 week old mice retinas with a targeted mutation of the c‐mer proto‐oncogene tyrosine kinase gene (Mertk−/−) and characterized for expression of microglia specific markers. Extracellular vesicles were purified from 48h conditioned media of cultured microglia and characterized for expression of galectin‐3 and Alix, an exosome marker, using immunocytochemistry and Western blots.ResultsRetinal microglia from Mertk−/− mice displayed an activated phenotype characterized by expression of CX3Cr1, CD11b, and Griffonia simplicifolia isolectin B4 but not of the Müller glial marker glial fibrillary acidic protein (GFAP) nor the vascular endothelial cell marker PECAM‐1. Intense galectin‐3 immunofluorescence was observed throughout the cell body and processes of microglial cells; producing a ~30 kDa galectin‐3 reactive band in the cytosolic component in Western blots. Abundant amounts of extracellular vesicles (~100–200 nm in size) secreted by the cells in 48h conditioned medium displayed a ~30 kDa galectin‐3‐reactive band and an Alix‐reactive band, consistent with exosomes, in Western blots.ConclusionsOur study shows that activated microglia isolated from early Mertk−/− mice with retinal degeneration expressed high levels of galectin‐3. Moreover, galectin‐3 co‐localized with Alix‐expressing exosomes secreted by cultured microglia. The increased production and release of exosomal galectin‐3 by activated retinal microglia support a potential role for galectin‐3 and microglial cells in the mechanisms of degenerative retinal diseases.
Development of a new technique of embalming and preservation until almost one year at room temperature and dry storage: histological and microbiological analysis
Authors: Masuko Telma Sumie , Dos Santos Andrade Lucas , Ottone Nicolas Ernesto , Baptista Carlos Augusto Camargo , Mimica Marcelo Jenne , Barros Mirna Duarte 
Published: April 2020

IntroductionIn recent years, a large number of fixation and preservation liquids have been proposed in the search for alternative methods of body preservation. Two processes occur postmortem: putrefaction with bacterial action on body tissues and autolysis with decomposition of the body by endogenous substances. Thus, we intend to present a new formula that allows the body to be preserved with its morphological and mobility characteristics similar to the fresh cadaver, but ensuring its fixation and conservation over time, maintaining at room temperature.Material and MethodWe use a donated 69‐years‐old female body, was embalmed using a new solution based on Baptista et al. (1986) with embalming pump. The formula used was: alcohol 1000 ml; phenol 1000 g; glycerin 1000 ml; sodium nitrate 1000 g; formaldehyde 2000 ml; distilled water 14000 ml. Arterial accesses and complementary injections of formaldehyde were performed in muscles limbs and cranial cavity. The cadaver was maintained at room temperature, ranging from 20.1 to 32.6 °C (68.18–90.68 °F) and the humidity (41–94) in body bag covered with blackout sheet. Samples of tissues (skin and subcutaneous tissue, rectus abdominis muscle, quadrate lobe of liver, transverse colon and brain) were collected after 130, 150, 185, 360 and 512 days of embalming and submitted to histological staining (HE). For the microbiological analysis we used samples after 185 and 360 days and seeded on agar plates (blood, chocolate, and Sabouraud) and placed in liquid medium (TSB) and incubated for 72 hours (35–37 °C).ResultsThis method resulted in soft and flexible cadavers as can be seen at elbow joint (Figs.
1a, 1b) with almost natural colors (Fig.
2). Histological analysis indicated the preservation of tissue and cellular structure in the different samples examined, even after 512 days post‐embalming: skin and subcutaneous tissue (Fig.
3); muscle (Fig.
4); liver (Fig.
5) and brain (Fig
6). The cultures were negative for growth of microorganisms in both analysis (after 185 and 360 days).DiscussionThe cadaver preservation technique presented has low cost and easy execution, being effective in maintaining the morphological characteristics of the anatomical specimen for an extended period of time.ConclusionIt presents as an alternative to anatomical teaching and research centers that have to deal with the toxicity of fixation products and the costs of obtaining and maintaining anatomical specimens.Demonstration of the cadaver elbow joint flexibility after 512 days post embalming;Figure 1Aspect of the coloration of the tissues of the abdominal organs, 360 days post embalming.Figure 2Histological sections after 512 days of fixation of skin and subcutaneous tissue, muscle, liver and brain, respectively. HE. 200x.Figure 3
Preliminary biochemical characterization of Flavin Dependent Monooxygenase DszA
Authors: Sanchez Misael , Tavassoli Alireza , Palfey Bruce , Vey Jessica 
Published: April 2020

Sulfur dioxide production through fossil fuel combustion is a major contributor to atmospheric pollution. This molecule has been known to cause respiratory illness in humans and land deterioration through acid rain formation. Fortunately, the biodesulfurization pathway (BDS) in R. erythropolis and other bacterial species have shown promise in becoming a useful tool for the removal of sulfur from crude oil. However, improvements are still necessary for this pathway to become competitive and industrially applicable. Our current objectives are to rationally design the BDS pathway in R. erythropolis, starting with enzymes DszC and DszA. The project goal is to decrease substrate specificity in the pathway, allowing it to work on a larger selection of organosulfur compounds found in fossil fuels. Here we exhibit preliminary biochemical characterization of the second enzyme in the BDS pathway, DszA, a flavin dependent monooxygenase. Stopped‐flow spectrophotometric studies are being used to monitor the reduced flavin dissociation constant(Kd) as well as its rate of oxidation in the presence or absence of DszA and its native substrate, DBTO2. A 20.3 ± 0.451 μM Kd value was determined for the reduced form of flavin. As expected, flavin oxidation increases with oxygen concentration in the presence of DszA. The rate of flavin oxidation also increases in the presence of both DszA and DBTO2 compared to DszA alone, suggesting that the oxidation we observe is enzymatically mediated. Contrary to previous studies, which suggested the production of a flavin‐N5‐oxide intermediate during catalysis, we have not observed the formation of flavin‐N5‐oxide. This intermediate should be detectable through stopped‐flow experiments. Our work towards confirming our enzyme’s activity and ability to generate either the N5‐oxide or the better‐understood C4a‐(hydro)peroxyflavin intermediates is ongoing.Support or Funding InformationCalifornia State University Program for Education in BiotechnologyNIH Grant 5SC3GM122652
Exercise Improves the Fasting Regulation of Skeletal Muscle Protein Synthesis in Tumor Bearing Mice
Authors: Halle Jessica , Fix Dennis , Counts Brittany , Carson James 
Published: April 2020

IntroductionCancer is a debilitating disease that is often accompanied by decreased physical activity and chronic energetic stress that disrupts muscle proteostasis. Skeletal muscle protein turnover is highly sensitive to changes in feeding and activity. Raptor (Ser 792) and TSC1/2 (Ser 1387) phosphorylation can inhibit mTORC1 activation and suppress anabolic signaling, which has been implicated in cancer‐induced skeletal muscle wasting.PurposeTo examine the effect of the cancer environment on the fasting regulation of Raptor and TSC1/2 in male ApcMin/+ mice and determine if increased physical activity could alter this response.MethodsMale C57BL/6 (B6, N=24) and ApcMin/+ (MIN, N=31) mice were either sacrificed under ad libitum conditions (B6‐fed, M‐fed), fasted for 12hrs (B6‐fast, M‐fast), or fasted for 12hrs following 4wks of voluntary wheel running (B6+W, M+W). TSC1/2 serine 1387 and Raptor serine 792 were measured in the gastrocnemius muscle as phosphorylation to total ratio by western blot. Protein synthesis was measured by puromycin incorporation.ResultsAll MIN mice exhibited body weight loss (p<0.001) and reduced gastrocnemius mass (p<0.001) when compared to all B6 mice. Raptor phosphorylation (pRaptor) was induced in M‐fast compared to M‐fed (p=0.019), which was not changed by fasting in B6 mice (p=0.414). TSC1/2 phosphorylation was induced in M‐fast compared to M‐fed (p=0.001) and in B6‐fast to B6‐fed (p=0.039). Puromycin was trending to be reduced in M‐fast compared to MIN‐fed (p=0.070), but there was no change in B6‐fast to B6‐fed (p=0.323). Raptor phosphorylation was not different in M‐fast compared to M+W (p=0.302), however pRaptor was reduced in B6+W compared B6‐fast (p=0.028). TSC1/2 phosphorylation (p=0.001) and puromycin (p=0.016) were induced in MIN+W compared to M‐fast, with no changes in the B6‐fast to B6+W (p=0.360, p=0.196; respectively).ConclusionsOur results provide evidence that the cancer environment disrupts fasting regulation of mTORC1 in skeletal muscle. Interestingly, TSC1/2 phosphorylation was sensitive to fasting independent of the tumor environment, while wheel activity induced protein synthesis independent of Raptor phosphorylation. Therefore, further study is warranted to determine physical activities regulation of fasting skeletal muscle protein synthesis in tumor bearing mice.Support or Funding InformationAcknowledgementsNCI R01‐CA121249
Redox and light signals in the partitioning of photosynthetic electrons
Authors: Puthiyaveetil Sujith , Ibrahim Iskander M. 
Published: April 2020

The light‐driven electron transport reactions of photosynthesis convert the free energy of sunlight into usable chemical energy. Plants contain two primary electron transport pathways: the linear electron transport from water to NADP+, producing NADPH and ATP, and the cyclic electron flow around photosystem I, generating just ATP. Recent research from our laboratory reveals that the sensory and gene regulatory function of a Chloroplast Sensor Kinase (CSK) is central to the partitioning of electrons into the linear and cyclic pathways. A conserved iron‐sulfur cluster enables CSK to sense the redox state of the electron carrier plastoquinone. CSK thus places the expression of multiple chloroplast genes under the regulatory control of plastoquinone. Through the phytochrome photoreceptor, light provides a further fail‐safe input into chloroplast gene regulation. The combined action of redox and light signals brings about stoichiometric changes in electron transport complexes with important implications for the flow of photosynthetic electrons.Support or Funding InformationPurdue University, Showalter Trust, and AgSEEDThe CSK‐based genetic switch in chloroplastsFigure 1
In Defense of Intrinsic Efficacy: The Didactic Value of a Modern Implementation of Furchgott’s Views on Agonism
Authors: Iniguez-Lluhi Jorge Alberto 
Published: April 2020

Mastery of fundamental pharmacology concepts is a defining characteristic of basic science graduate pharmacology programs. The acquisition of these skills, however, is challenging for most trainees and a solid understanding of the meaning and use of appropriate pharmacology terms such as efficacy, potency, receptor reserve, allostery and biased agonism is often not fully realized.In an effort to overcome these challenges, I have developed a consistent stepwise approach to the introduction of concepts that involves a modern and expanded implementation of Furchgott’s classical views of agonism. Although largely superseded by the Black and Leff operational model of agonism, Furchgott’s approach has distinct didactic advantages by clearly separating properties of the drug/receptor complex (intrinsic efficacy) from the specific properties of the system that interprets the stimulus generated by the receptor species (sensitivity). This approach lends itself readily to useful didactic analogies that can be implemented and illustrated in the teaching environment and are easier to conceptualize by the learners. To illustrate the behavior of this model, an easy to use simulation tool has been developed in the widely used Excel platform that allows learners to manipulate individual parameters such as affinity, intrinsic efficacy, number of receptors and sensitivity of the system to explore their influence on the shape and position of concentration response and ligand occupancy curves. Furthermore, this formalism is readily expanded in a stepwise manner to introduce progressively more advanced concepts such as interactions between two different ligands, as well as concepts of constitutive activity and allostery. These functionalities are revealed progressively in the simulation tool such that nearly all forms of major scenarios can be explored, including concepts such as receptor reserve, competitive antagonism, inverse agonism, and allosteric effects on both affinity and/or efficacy.The power of this approach is also evidenced by the fact that it is easy to illustrate to the learners not only how different mechanisms can yield similar functional outcomes but also to allow them to explore and identify experiments that can most clearly distinguish between them. This overall didactic approach has proven effective in diverse environments ranging from Medical Student instruction, Doctoral and Masters Pharmacology programs, Doctor in Pharmacy as well as advanced undergraduate courses.Pharmacodynamics simulation tool depicting the functional interaction between an orthosteric and allosteric ligand on two linked responses.Figure 1
Stereotactic Radiosurgery Effect on Ion Channel Activity: Implications in Metastasis and Cancer Pain Relief
Authors: Azorin-Vega Erika Patricia , Picones Arturo , Moranchel Mario , Oros Rigoberto 
Published: April 2020

Influence of aberrantly expression ofvoltage‐gated sodium channels (VGSCs) in metabolic regulation, cell cycledistribution, proliferation, radioresistance and metastasis confirm their role incarcinogenesis. Recently VGSCs have been proposed as prognostic markers andantimetastatic targets with diagnostic and therapeutic potential
[1]. Increasedsodium levels observed in cancer tissue, due to the persistent currents thatVGSCs develop under hypoxic conditions, have been correlated to tumor growth, invasiveness and metastasis
[2]. Quality of life of bone metastasis patientssignificantly improves after radiotherapy (10 fractions of 3Gy or 1 fraction of8 Gy) due to the control of tumor spreading and the sustained pain relief
[3,
4]. Mechanism trough which radiotherapy controls tumor spread and achieves painrelief is poorly understood. In the present work the role of VGSCs in tumorcontrol and pain relief mechanisms after irradiation were analyzed by invasionassays and whole‐cell patch clamp. Monolayers of NaV1.7 expressing and wildtype CHO cells were irradiated in a LINAC. SL 15 Phillips (8X8 cm2 field, 6MV xrays, gantry 180°) before evaluating the clonal and invasive capacity of cellsand the function of NaV1.7. Resuls show that NaV1.7 expression reduces CHOcells plating efficiency and confers radioresistance. Irradiation reduces sodiumcurrent density and increased the voltage to hyperpolarize. Apparently, irradiationdelayed NaV1.7 activation and significantly abolished invasiveness induced byradiotherapy.Support or Funding InformationThis study was performed as part of the activities of the “Laboratorio Nacional de Investigación y Desarrollo de Radiofármacos‐CONACyT”. Grant 293334.NaV1.7 expression reduces CHO cells plating efficiency and confers radioresistanceFigure 1NaV1.7 expression (red line) confers radioresistance to CHO cells (black line)Figure 2