bluuebunny/crossref_metadata_2025_split huggingface dataset:
Matrix metalloproteinase 13 (MMP13) can cleave the protease‐sensitive hinge region of theTransforming Growth Factor β (TGFβ) large latent complex
Authors: Reese Betsy , Routson Stephanie M , Lau Shukkwan , Lombard Frederick , Selim Abdulhafez A , D'Angelo Marina 
Published: June 2021

In this study, we demonstrate that MMP13 can utilize the protease‐sensitive hinge region of the TGFβ large latent complex as a substrate. Our lab has previously demonstrated that chondrocytes produce a unique large latent TGFβ complex that contains MMP13 in non‐covalent association. Our bioinformatics model suggests that MMP13 associates with the complex in such a way as to line up the catalytic domain with the protease sensitive hinge region, the site of release of the complex from extracellular matrix storage. Kinetic analysis of MMP13 catalytic domain digestion of a fluorescence‐labeled peptide, REHGARS, (the site of release of the TGFβ large latent complex from the extracellular matrix), indicated that the peptide was digested by MMP13 (30 minute slope = −2.580 and p‐value = 0.001 compared to substrate alone), and this activity was sensitive to a general inhibitor of MMP activity. A scrambled sequence of the peptide was not digested by MMP13 (30 minute slope = −0.2196). MMP2 and MMP9 catalytic domains were not as efficient in digestion of the substrate, but proteases present in cartilage extracts from chick embryonic sterna were able to digest the hinge region substrate. This is the first study of its kind indicating the ability of MMP13 to utilize the protease‐sensitive hinge region of the TGFβ large latent complex as a substrate, indicating a role for MMP13 in TGFβ activation. The implications of this finding provide a mechanism of release of matrix stored TGFβ in normal cartilage maturation as well as the aberrant release of articular cartilage stores of TGFβ in osteoarthritis.This work was supported in part by a grant from the Center for Chronic Disorders of Aging.
Human epithelial stem cells in corneal regeneration and epidermal gene therapy
Authors: De Luca Michele , Rama Paolo , Mavilio Fulvio , Pellegrini Graziella 
Published: June 2021

Adult stem cells are cells with a high capacity for self‐renewal that can produce terminally differentiated progeny. Stem cells generate an intermediate population of committed progenitors, often referred to as transit amplifying (TA) cells, that terminally differentiate after a limited number of cell divisions. Human keratinocyte stem cells are clonogenic and are known as holoclones. Human corneal stem cells are segregated in the limbus while limbal‐derived TA cells form the corneal epithelium. Self‐renewal and proliferation and deifferentiation of limbal stem cells are regulated by the ΔNp63 (α,β and γ), C/EBPδ and Bmi1 transcription factors. Cultivated limbal stem cells generate sheets of corneal epithelium suitable for clinical application. We report long‐term (up to 10 years) clinical results obtained in an homogeneous group of 112 patients presenting with corneal opacification and visual loss due to chemical burn‐dependent limbal stem cell deficiency. The corneal epithelium and the visual acuity of these patients have been restored by grafts of autologous cultured limbal keratinocytes. Clinical results were assessed by Kaplan‐Meyer, Chi‐square, Mann Whitney, Mc‐Nemar and Kruskal‐Wallis statistical analyses.Mutations in genes encoding the basement membrane component laminin 5 (LAM5) cause junctional epidermolysis bullosa (JEB), a devastating and often fatal skin adhesion disorder. Epidermal stem cells from an adult patient affected by LAM5‐β3‐deficient JEB were transduced with a retroviral vector expressing the β3 cDNA and used to prepare genetically corrected cultured epidermal grafts. Nine grafts were transplanted onto surgically prepared regions of the patient's legs. Engraftment was complete after 8 days. Synthesis and proper assembly of normal levels of functional LAM5 was observed, together with the development of a firmly adherent epidermis that remained stable for the duration of the follow‐up (3.5 years) in the absence of blisters, infections, inflammation or immune response. Proviral integration site analysis indicated that the regenerated epidermis is maintained by a defined repertoire of transduced stem cells. These data show that ex vivo gene therapy of JEB is feasible and leads to full functional correction of the disease.
Differential effects of acute gonadal steroid treatment on neuronal survival in the brainstem following C3 hemicontusion
Authors: Monaco Gina N , Khan Talat A , Ogata Kengo , Houle John D , Jones Kathryn J 
Published: June 2021

Following gonadectomy, adult male and female Sprague‐Dawley rats underwent a cervical level 3 hemicontusion spinal cord injury (C3HC SCI) and were randomized to receive testosterone (T), estrogen (E), or sham pellet, and True Blue (TB)‐soaked gelfoam was placed into the lesion cavity to retrogradely label injured supraspinal neurons. At 4 weeks post‐C3HC, brains and cervical spinal cords were removed, sectioned, fixed, mounted, and examined with fluorescence microscopy for TB‐labeled neurons. Neurons in the red nucleus and lateral vestibular nuclei were counted from alternating sections. For the lateral vestibular neurons: sham‐treated males exhibited greater baseline cell survival than did females following injury, T had a positive effect on cell survival in female animals, but E had a negative effect on cell survival in female animals. In the red nucleus, cell survival was similar between the sham‐treated sexes, T did not have an effect on cell survival in females, and E had a negative effect on cell survival in females. The results suggest there are sex differences in the response to injury in different brain stem nuclei, as well as differential and regional effects of T versus E treatments on cell survival. This work was supported by VA Rehab R&D Merit Review Project # B4952I (KJ Jones & JD Houle).Grant Funding Source: VA Rehab R&D Merit Review Project # B4952I (KJ Jones & JD Houle)
Comparative morphology of the rat optic nerve using light and electron microscopy
Authors: Duncan Joshua Kyle , Anderson Bryan , Kaufman Jason A. , Iwaniuk Andrew , Jones T. Bucky , Bray Douglas , Suchocki Lawrence , Hall Margaret I. 
Published: June 2021

Optic nerve fibers are the axons of retinal ganglion cells, and as such they can provide information about the visual acuity and sensitivity capabilities of an animal. Consistent optic nerve fiber counts are not currently available for most animals. In this study, using light microscopy, we counted optic nerve fibers for 7 nerves from 4 adult Sprague‐Dawley rats. Using unbiased stereology we counted 4 adjacent sections of each nerve at 1000X, each using a different staining technique, including Bielschowsky's silver impregnation, Bodian's protagarol, Luxol Fast Blue stain, and a combination Bodian's protagarol and Luxol Fast Blue. We obtained counts of 75,000 to 90,000 fibers, with a fiber size range of 0.1μm to 5μm. We also examined preliminary electron micrographs of one Sprague‐Dawley rat optic nerve at magnifications up to 10,000X. Published counts of the pigmented rat optic nerve fibers using electron microscopy are 120,000, with a size range of 0.4μm to 5μm. This is significantly higher than our light microscopy counts. However, using EM at 10,000X we observe myelinated fibers as small as 0.02.μm. This discrepancy in fiber numbers calls into question which methodology is most suitable for counting myelinated fibers within the optic nerve.Grant Funding Source: Kenneth A. Suarez fellowship
Effects of a high soy protein diet on forelimb function after stroke in rats
Authors: Burnet Derek , Strieker Shanna M. , Butteiger Dustie N. , Banz William J. , Cheatwood Joseph L. 
Published: June 2021

Dietary strategies aimed at increasing post‐stroke outcomes are lifestyle alterations which could be easily implemented by people at risk of stroke. Soy diets have been demonstrated to provide some benefits in the short term following stroke, but longer time periods have not been studied. Further, carefully defined diets containing soy protein isolates have not been investigated. In the current study, male LE Hooded rats were fed semi‐ purified diets containing either sodium caseinate or a soy protein isolate. Rats were trained to perform the skilled forelimb reaching task and subsequently underwent unilateral middle cerebral artery occlusion (MCAO) to induce a stroke lesion. After stroke, rats remained on the same diet and were tested daily for a period of 8 weeks to observe their performance on the skilled forelimb reaching task. In the first and second weeks following stroke, rats which were fed the soy protein diet demonstrated less severe reaching deficits than rats fed the casein diet (p<0.05). Further, rats fed the soy protein diet reached statistical recovery to within baseline range at three weeks post‐stroke. Casein‐fed rats did not reach statistical recovery within the time course of the study. These results indicate that a diet rich in soy protein provides some protection from neurological damage following MCAO stroke in rats and may encourage a more rapid spontaneous recovery of skilled forelimb reaching.Grant Funding Source: none
Sural nerve morphology in hypertensive rats with chronic diabetes
Authors: Sanada Luciana Sayuri , Tavares Marcelo Rodrigo , Neubern Milena , Fazan Valéria Paula 
Published: June 2021

Despite that the association between hypertension and diabetes is common in clinical practice, the contribution of each isolated entity in the neuropathy development is still not known. The literature lacks a morphologic description of peripheral nerves in experimental models of hypertensive diabetic animals. The present study compared the sural nerve in Wistar rats (WR), WR with chronically induced diabetes, spontaneously hypertensive rats (SHR) and SHR with chronically induced diabetes, using a morphological approach. Female SHR and WR, 8 weeks old, received a single intravenous injection of streptozotocin (STZ) through the caudal vein. Twelve weeks after the injection, right and left sural nerves were dissected and proximal and distal segments were prepared for light microscopy. Morphometry was performed with the aid of computer software. Fascicular and myelinated fiber data from sural nerves in control and diabetic WR are statistically larger compared to SHR and diabetic SHR. Hypertension did alter the morphology and morphometry of the fascicles and myelinated fibers of the sural nerves in control SHR compared to control WR. Chronic diabetes also induced alterations of the morphology and morphometry of sural nerve. Hypertension alteration caused an exacerbation of the diabetic alterations already observed in neuropathic degeneration of sural nerves.Grant Funding Source: FAPESP
Renshaw cell loss in a transgenic mouse model of amyotrophic lateral sclerosis
Authors: AlMarsoummi Sarmad , Blanchard Stephane , Kulikov Sergei , Smith Margaret , Carr Patrick 
Published: June 2021

The distribution and abundance of immunohistochemically‐identified Renshaw cells was studied in the lumbar spinal cord of an amyotrophic lateral sclerosis (ALS) mouse model. Transgenic G93A‐SOD1 mice displayed ALS‐like disease with the first neurological sign occurring at 90 days of age and progression at 100 to 150 days of age. Gephyrin and calbindin D28k immunofluorescence were used to identify and count the putative Renshaw cells in lumbar spinal cord tissue from mice at 40, 70, 90 and 145 days of age. Preliminary results suggest that in this model of ALS, functional neurological deficits are preceded and accompanied by a profound loss of gephyrin‐ and calbindin D28k labeled putative Renshaw cells. In 30 micron sections of lumbar spinal cord, mean counts per ventral horn were: at 40 days ALS=1.73 and control=3.13; at 70 days ALS=2.00 and control=3.32; and at 90 days ALS=2.22 and control=3.28; and at 145 days ALS=1.39 and control=3.08. Differences were significant (p<0.05; Mann‐Whitney Rank Sum test) for all ages. A significant decrease in number of Renshaw cells weeks prior to the onset of the disease suggests that, in the B6.Cg‐Tg(SOD1‐G93A)1Gur/J transgenic mouse model, the loss of motor‐related interneurons precedes clinical neurological deficit onset and progression of the disease and the loss of Renshaw interneurons occurs before the onset of motor neuron death.Supported by NIH 5R01HL075034‐05.Grant Funding Source: NIH
On the developmental origin of hepatic sinusoidal endothelium: confirmation of angiocirculatory vasculogenesis
Authors: Meyer Anna C. , Sherer Glenn K. 
Published: June 2021

Developmental mechanisms reported to account for the origin of hepatic sinusoidal endothelium include (1) in situ differentiation of mesenchymal cells (Sherer, 1991), (2) sprouting from preexisting vessels (Gouysse et al., 2002), (3) transdifferentiation of mesothelial cells (Pérez‐Pomares et al., 2004), and (4) recruitment of angioblasts and/or vascular endothelial cells (VECs) from the circulation (Pardanaud & Eichmann, 2006; Zhang et al., 2006). The present study was designed to investigate whether the last of these mechanisms, here termed angiocirculatory vasculogenesis, plays a role in the development of hepatic sinusoidal endothelium. Chick livers were harvested from quail/chick parabioses maintained either in ovo or in shell‐less culture and were examined for evidence of quail VECs by immunostaining with QH1 antibody. Numerous positively‐stained cells were found to contribute to the sinusoids of parabiotic chick livers. Non‐parabiotic chick liver, serving as a negative control, lacked staining. These findings confirm that at least some of the cells that form these capillary‐level vascular structures are, as previously reported, acquired from circulating blood.Grant Funding Source: None
Pretreament with losartan affects the inflammation following cardiac injury
Authors: Le Saux Claude Jourdan , Miyasato Shelley , Rueli Rachel 
Published: June 2021

Activation of the local renin‐angiotensin system (RAS) following cardiac injury participates in remodeling process. We hypothesized that mice treated with losartan, an angiotensin II receptor blocker, will prevent TGF‐b signaling activation leading to attenuated remodeling.C57BL/6J mice, 8–10 weeks old underwent cryoablasion of the left ventricle. At day 21 mice received losartan (0.6g/l) in their drinking water until sacrificed. Heart tissue was collected at several time points. The inflammatory response was determined by characterization of immune cell infiltration and cytokine mRNA abundance. Cardiac remodeling was assessed by extracellular matrix gene expression and quantification of collagen deposition by picrosirius red stain. TGF‐b signaling activation was determined by western blot analysis.All mice showed a peak of inflammation at day 3, and resolution by day 14. Pretreatment with losartan significantly increased macrophage infiltration. It significantly increased TNF‐a; mRNA at days 3 and 14. The level of TGF‐b mRNA was not affected by losartan, and none of the TGF‐b signaling pathways were activated. Correspondingly, collagen deposition did not significantly change.In contrast to other studies where losartan was given at the onset of injury, treatment prior to induction of cardiac injury may enhance inflammation, while modestly attenuating fibrosis.Grant Funding Source: NIH‐NCRR RR016453, Hawaii Community Foundation 20080485
Towards a chemical anatomy: new tools to image biological molecules in cells and in tissues
Authors: Salic Adrian 
Published: June 2021

Microscopic imaging has revolutionized our understanding of the structure and function of cells and tissues. At its best, microscopy can detect cellular components with high sensitivity and spatial resolution. Additionally, live imaging allows dynamic cellular processes to be studied in a non‐invasive manner, with high temporal resolution.In the last decade, a small number of chemical reactions have been developed which occur with high efficiency and specificity under mild conditions, in aqueous media. These reactions are bio‐orthogonal, involving chemical groups not found in cells and inert toward naturally occurring chemical groups. These reactions are thus ideal for labeling and detecting molecules in vivo. One focus of our lab is to develop chemical technologies for metabolic labeling and direct imaging of biological molecules, based on these bio‐orthogonal chemical reactions. My talk will present our recent work on devising novel biosynthetic probes to image nucleic acids and lipids in cells and in tissues.
The Role of Genetic Polymorphism of Beta‐3‐Adrenergic Receptor in The Susceptibility to Diabetes and Its Related Disorders
Authors: El Din Hemimi Neveen Salah , El Salam Mona Mohamed Abd , Tawfik Lamis M , Khalil Marwa Mahmoud 
Published: June 2021

BackgroundThe β3 – adrenergic receptor (β3 AR) is mainly expressed in adipose tissue and plays an important role in lipid metabolism and metabolic rate by mediating lipolysis and thermogenesis. It has been suggested that the Trp 64Arg (T→C) polymorphism in the β3 AR gene affects fat accumulation and/or impairment of lipid and carbohydrate metabolism.ObjectiveTo investigate if common polymorphism (Trp 64 Arg) of β3 AR gene, has a role in the apparent susceptibility to type 2 DM and its related disorders.Material& Method135 normal individual and 123 type 2 diabetic patients were enrolled in the study. The β3 AR Trp 64 Arg polymorphism was identified by restriction fragment length polymorphism polymerase chain reaction (RFLP‐PCR) of peripheral blood DNA samples. Analysis of data was done by using SPSS program.ResultsAllele frequency for C was 23.2% in the diabetic group compared to 12.2% in the control group. The carriers of XC genotype (TC and CC) were at high risk of developing type 2 DM (OR= 2.8; 95% CI = 1.6–4.9) when compared with the carrier of TT genotype. Furthermore they were at much higher risk of developing its related disorders such as central and abdominal obesity, dyslipidemia and hypertension (OR= 2.8; 1.8, 1.5, 2.2 and 2.7) for BMI, WHR, TG, HDL and hypertension respectively.ConclusionArg 64 allele is a risk factor for DM and its related disorders.Source of Fund: Ain Shams University.
Long‐Extension PCR Studies of Mitochondrial DNA Deletions in Irradiated MOLT‐4 (Human Acute Lymphoblastic Leukemia) Cells and Pearson's Syndrome Fibroblasts
Authors: Lynch Zachary , Pogozelski Wendy 
Published: June 2021

Mitochondrial DNA, a double‐stranded circle, undergoes large‐scale deletion events. In humans, many of these mitochondrial DNAs that bear deletions can accumulate and compromise energy production. Cells with high energy demands are particularly affected, leading to a variety of disorders. As a first step in an effort to determine how these large‐scale deletions arise, we have developed a long‐extension PCR assay that detects these deletions. Here we show the assay used to observe deletions in the mtDNA of γ‐irradiated human MOLT‐4 cells (a lymphoblastic cell line) as well as in a fibroblast cell line derived from a boy known to have elevated levels of a 4977‐bp deletion called the “common deletion”.This research was sponsored by the Camille and Henry Dreyfus Foundation, the Geneseo Foundation and the SUNY Geneseo Student Association.
Effect of administration of ethanol extract of Eryngium carlinae on diabetic rats
Authors: Noriega‐Cisneros Ruth , Ortiz‐Avila Omar , Salgado‐Garciglia Rafael , Arellano‐Plaza Melchor , Clemente‐Guerrero Mónica , Manzo‐Avalos Salvador , Saavedra‐Molina Alfredo 
Published: June 2021

Diabetes mellitus is a metabolic disorder of multiple etiologies, characterized by chronic hyperglycemia, that is directly related to the development of long‐term complications which determine the quality of life of diabetic patients. At present is counted a variety of palliative medicine to treat this disease, however, some are beyond the reach of all people by their high cost.ObjectiveThe aim of this study was to investigate the effect of administration of the ethanol extract of Eryngium carlinae (EC) in diabetic rats.MethodsWere measured glucose levels in blood and weight of the rats, likewise, was measured the food and water intake for 30 days, during which conducted oral administration (in drinking water) of the extract in a dose of 150 mg/kg. Diabetes was induced by a single injection (ip) of streptozotocin (40 mg/kg), rats with glucose levels above 300 mg/dL were used to shape the diabetic groups.ResultsThe administration of extract of EC had no hypoglycemic effect; however, its use was able to reduce the weight loss characteristic of diabetic model. The symptoms of polyphagia and polydipsia were present in the diabetic group, as evidenced by the high consumption of food and water, compared with a no diabetic group (p <0.01) despite receiving treatment with extract.ConclusionDue to the results, currently being tested by varying the route of administration and dose of EC extract to find effective dose is also possible to evaluate the antioxidant activity of extract in different organs.
Rehybridization of Promoter DNA Targets in Chromatin to Discover Transcription Factors of Oncogenes
Authors: Zhang Huiping , Haegele Joseph , Shin Woo‐Cheol , McGown Linda B 
Published: June 2021

Identification of transcription factors (TF) assembled at promoter regions of oncogenes is vital to understand how gene expression is altered in cancer and in tumor microenvironments. Most TF identification methods are based on one‐on‐one DNA/protein interactions in vitro, which may not reflect DNA/protein interactions in vivo and may overlook protein complex information. Moreover, existing methods for chromatin pull down target pre‐identified proteins rather than DNA, which limits the ability to discover new proteins that may bind to specific genomic sequences. We are pursuing a new approach, chromatin rehybridization (CR), which preserves and detects DNA/protein and protein/protein interactions that occur in live cells and targets specific DNA sequences rather than associated proteins.The G‐quadruplex forming Pu27‐mer located upstream of the c‐MYC oncogene and its associated TFs including cellular nucleic acid binding protein (CNBP) serve as the model system for development of the CR technique. Preliminary results demonstrate that CNBP is pulled down with the targeted Pu27‐mer in MCF‐7 cells using CR. At least one unreported TF associated with c‐MYC was also detected and will be identified using mass spectrometry.The CR method addresses the need for full proteomic analysis of particular genomic regions. This work is supported by NIH through grant R21 CA134419‐01A1.
Mediator Structure and Interaction with the Basal Transcription Machinery
Authors: Asturias Francisco J , Cai Gang , Imasaki Tsuyoshi , Yamada Kentaro , Cardelli Francesco , Takagi Yuichiro 
Published: June 2021

Understanding the structure and conformational dynamics of Mediator is critical for unraveling the essential role the complex plays in regulation of eukaryotic transcription initiation. We used single particle macromolecular electron microscopy (EM) to study the conformational variability of Mediator and that information enabled us to determine a cryo‐EM structure of the complex at ~26Å resolution. Comparing the structures of free and RNA polymerase II (RNAPII)‐associated Mediator made possible a detailed description of Mediator structural modules and the rearrangement they undergo upon interaction with RNAPII, both of which appear to be conserved from yeast to humans. We have also pursued independent EM analysis of the Head module responsible for control of the Mediator‐RNAPII interaction. Conformational analysis of a recombinant Head module revealed distinct conformations and comparison with the structures of sub‐complexes provided information about subunit organization. All of this information, along with results from biochemical and structural analysis of the interaction of the Head module with the TATA‐binding protein (TBP) and RNAPII subunits Rpb4 and Rpb7, suggest a possible mechanism for Mediator regulation of RNAPII interaction with promoter DNA.Supporteb by NIH R01 GM67167