27 results on '"Witting S"'
Search Results
2. P1453: STABLE TRANSDUCTION OF FETAL HEMOGLOBIN IN PATIENTS WITH SICKLE CELL DISEASE IN THE PHASE 1/2 MOMENTUM STUDY OF ARU-1801 GENE THERAPY AND REDUCED INTENSITY CONDITIONING
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Grimley, M., primary, Kent, M., additional, Asnani, M., additional, Shrestha, A., additional, Felker, S., additional, Lutzko, C., additional, Arumugam, P., additional, Witting, S., additional, Knight-Madden, J., additional, Niss, O., additional, Quinn, C., additional, Lo, C., additional, Little, C., additional, Dong, A., additional, and Malik, P., additional
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- 2022
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3. Characterization of a third generation lentiviral vector pseudotyped with Nipah virus envelope proteins for endothelial cell transduction
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Witting, S R, Vallanda, P, and Gamble, A L
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- 2013
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4. Differences in vector-genome processing and illegitimate integration of non-integrating lentiviral vectors
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Shaw, A M, primary, Joseph, G L, additional, Jasti, A C, additional, Sastry-Dent, L, additional, Witting, S, additional, and Cornetta, K, additional
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- 2016
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5. Dravet syndrome patients with genetically confirmed diagnosis
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Witting, S., primary, Troncoso, M., additional, Ortega, P., additional, Rojas, C., additional, Salvo, D., additional, López, C., additional, and Fariña, G., additional
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- 2015
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6. Seizures not related to hypoglycemia in type 1 diabetic patients (Dm1)
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Saez, V., primary, Hernández, A., additional, Witting, S., additional, Rojas, C., additional, López, M., additional, Troncoso, M., additional, and Henríquez, K., additional
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- 2015
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7. Paroxysmal dyskinesias in pediatric patients
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Troncoso, M., primary, Barrios, A., additional, Balut, F., additional, Witting, S., additional, López, C., additional, Saez, V., additional, Guzmán, G., additional, Coria, C., additional, Díaz, C., additional, Flandes, A., additional, and Henríquez, K., additional
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- 2015
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8. West syndrome in patients with down syndrome. Clinical description and management
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Rojas, C., primary, Witting, S., additional, Ortega, P., additional, Faure, F., additional, and Gutiérrez, J., additional
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- 2015
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9. Electric sleep status: clinical and electroencephalographic description
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Lopez, F., primary, Muñoz, D., additional, Mendoza, A., additional, Parra, P., additional, Rojas, C., additional, Hernandez, A., additional, Witting, S., additional, Troncoso, L., additional, Troncoso, M., additional, and Marquez, E., additional
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- 2015
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10. Epilepsy in patients with metabolic diseases, clinical features, study and treatment
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Witting, S., primary, Troncoso, M., additional, Micolich, V., additional, Santander, P., additional, Troncoso, L., additional, Barrios, A., additional, Rojas, C., additional, Faure, F., additional, Henríquez, K., additional, and Araya, S., additional
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- 2015
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11. Office Rents Not Cost Effective, Assumptions and Calculations
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Tempelmans Plat, H., Witting, S., and Real Estate and Urban Development
- Abstract
Office rents are not sufficient to compensate for the costs of the continuation of the exploitation process in the long run. Together with the book profit at the moment of sale, the rent may be sufficient merely to give a reasonable return on the historical investment. Viewing the exploitation process as an "ordinary" process, we have to value the investment on the basis of replacement value and relate the return to that value at each moment in time. It is furthermore important to take all costs into account: maintenance as well as decomposition or demolition. A net return of up to 3% less than the market rate of interest has to be expected.
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- 2002
12. Financieel duurzaam : de financiële voordelen van duurzaam ondernemen in vastgoed
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Witting, S. and Witting, S.
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- 2003
13. A confocal beam scanning white-light microscope
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Hell, S., primary, Witting, S., additional, Schickfus, M., additional, Resandt, R. W. Wijnaendts, additional, Hunklinger, S., additional, Smolka, E., additional, and Neiger, M., additional
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- 1991
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14. DISC - An Efficient Method for the Discretization of Convection on Unstructured Grids
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Rexroth, C.-H., Bauer, H.-J., and Witting, S.
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- 1997
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15. Genotype and Phenotype Characterization of Patients with Mucopolysaccharidosis IV-A in Chile.
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Cárdenas JM, Vergara D, Witting S, Balut F, Guerra P, Mesa JT, Silva S, Tello J, Retamales Á, Barrios A, Pinto F, Faundes V, and Troncoso M
- Abstract
Introduction: Morquio syndrome or mucopolysaccharidosis type IV-A (MPS IV-A) is an autosomal recessive disease caused by biallelic variants in the GALNS gene, encoding the lysosomal enzyme GalN6S, responsible for glycosaminoglycan keratan sulfate and chondroitin-6-sulfate degradation. Studies have shown that the degree of evolutionary and chemical divergence of missense variants in GalN6S when compared to ancestral amino acids is associated with the severity of the syndrome, suggesting a genotype-phenotype correlation. There is little information on Latin American patients with MPS IV-A that replicate these findings. This study aimed to characterize the phenotype and genotype from patients with MPS IV-A, who are under Enzyme Replacement Therapy at the Children's Neuropsychiatry Service of the Hospital Clínico San Borja Arriarán, Santiago, Chile, and to determine if there is any association between genotype and phenotype with those findings., Methods: Information was collected from medical charts, all patients went through a GalN6S enzymatic activity measurement in leukocytes from peripheral blood, and the GALNS gene was sequenced for all cases., Results: 12 patients with MPS IV-A were recruited, all patients presented multisystem involvement, mostly skeletal, and 75% of cases underwent surgical interventions, and cervical arthrodesis was the most frequent procedure. In regards of the genotype, the two most frequent variants were c.319+2T>C ( n = 10, 41.66%) and p.(Arg386Cys) ( n = 8, 33.33%), the first one was previously described in 2018 in a patient from Chile [Bochernitsan et al., 2018]., Conclusion: This is the first time that a genotype-phenotype correlation has been studied by analyzing the variants effect on the molecular structure of human GalN6S and the evolutionary conservation degree of affected residues in a cohort of patients in Chile. Albeit our work could not find statistically significant associations, we may infer that the evolutionary conservations of affected amino acids and the effect of variants on enzyme structure may play a main role. Further analyzes should consider a meta-analysis of published cases with genotype data and larger samples and include other variables that could provide more information. Finally, our data strongly suggest that variant c.319+2T>C could have a founder effect in Chilean patients with MPS IV-A., Competing Interests: The authors have no conflicts of interest to declare., (© 2023 S. Karger AG, Basel.)
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- 2023
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16. Exploring the Spectrum of RHOBTB2 Variants Associated with Developmental Encephalopathy 64: A Case Series and Literature Review.
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de Pedro Baena S, Sariego Jamardo A, Castro P, López González FJ, Sánchez Carpintero R, Cerisola A, Troncoso M, Witting S, Barrios A, Fons C, López Pisón J, and Ortigoza-Escobar JD
- Abstract
Background: Rho-related BTB domain-containing protein 2 ( RHOBTB2 ) is a protein that interacts with cullin-3, a crucial E3 ubiquitin ligase for mitotic cell division. RHOBTB2 has been linked to early infantile epileptic encephalopathy, autosomal dominant type 64 (OMIM618004), in 34 reported patients., Methods: We present a case series of seven patients with RHOBTB2 -related disorders ( RHOBTB2 -RD), including a description of a novel heterozygous variant. We also reviewed previously published cases of RHOBTB2 -RD., Results: The seven patients had ages ranging from 2 years and 8 months to 26 years, and all had experienced seizures before the age of one (onset, 4-12 months, median, 4 months), including various types of seizures. All patients in this cohort also had a movement disorder (onset, 0.3-14 years, median, 1.5 years). Six of seven had a baseline movement disorder, and one of seven only had paroxysmal dystonia. Stereotypies were noted in four of six, choreodystonia in three of six, and ataxia in one case with multiple movement phenotypes at baseline. Paroxysmal movement disorders were observed in six of seven patients for whom carbamazepine or oxcarbazepine treatment was effective in controlling acute or paroxysmal movement disorders. Four patients had acute encephalopathic episodes at ages 4 (one patient) and 6 (three patients), which improved following treatment with methylprednisolone. Magnetic resonance imaging scans revealed transient fluid-attenuated inversion recovery abnormalities during these episodes, as well as myelination delay, thin corpus callosum, and brain atrophy. One patient had a novel RHOBTB2 variant (c.359G>A/p.Gly120Glu)., Conclusion: RHOBTB2 -RD is characterized by developmental delay or intellectual disability, early-onset seizures, baseline movement disorders, acute or paroxysmal motor phenomena, acquired microcephaly, and episodes of acute encephalopathy. Early onsets of focal dystonia, acute encephalopathic episodes, episodes of tongue protrusion, or peripheral vasomotor disturbances are important diagnostic clues. Treatment with carbamazepine or oxcarbazepine was found to be effective in controlling acute or paroxysmal movement disorders. Our study highlights the clinical features and treatment response of RHOBTB2 -RD., (© 2023 International Parkinson and Movement Disorder Society.)
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- 2023
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17. Efforts to Prevent Railway Suicides in Denmark.
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Erlangsen A, la Cour N, Larsen CØ, Karlsen SS, Witting S, Ranning A, Wang AG, Ørnebjerg K, Schou B, and Nordentoft M
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- Humans, Suicide Prevention, Suicidal Ideation, Denmark epidemiology, Suicide, Railroads
- Abstract
Background: Reviews of camera surveillance systems have demonstrated ambivalent behaviors among people who die by railway suicide. Yet, only few preventive measures have been evaluated. Aims: We aimed to review incidents of suicidal behavior at a Danish railway station, install preventive measures, and monitor subsequent calls to a telephone helpline and reports of suicidal incidences. Method: Suicide incidents at Valby Station during 2012-2018 were reviewed to identify options for preventive measures. Based on these findings, signs encouraging help-seeking and other measures were implemented. Calls to the Danish helpline for suicide prevention and suicidal events at the station were subsequently monitored. Results: The review revealed locations where measures were meaningful and signs, physical barriers, and motion-sensitive lights were installed. Over the following 14 months, no suicide deaths occurred, and the signs were mentioned in 14 calls to the helpline, some of which were made by callers who were evaluated to be at high risk of suicide. Limitations: No direct link between implemented measures and observed outcomes could be established. Conclusion: Installing measures, including signs, at appropriate locations at railway platforms may encourage people in crisis to seek support.
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- 2023
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18. Super-refractory status epilepticus related to COVID-19 in a paediatric patient with PRRT2 mutation.
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Vergara D, Rubilar C, Witting S, Troncoso M, and Caraballo R
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- Adolescent, Anticonvulsants therapeutic use, COVID-19 complications, Female, Humans, Mutation, SARS-CoV-2, Status Epilepticus drug therapy, Status Epilepticus etiology, COVID-19 diagnosis, Membrane Proteins genetics, Nerve Tissue Proteins genetics, Status Epilepticus genetics
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- 2021
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19. Wound Closure After Port Implantation-A Randomized Controlled Trial Comparing Tissue Adhesive and Intracutaneous Suturing.
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Witting S, Ingwersen M, Lehmann T, Aschenbach R, Eckardt N, Zanow J, Fahrner R, Lotze S, Friedel R, Lenz M, Schmidt C, Miguel D, Ludriksone L, and Teichgräber U
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- Adult, Female, Humans, Male, Prospective Studies, Quality of Life, Suture Techniques, Sutures, Tissue Adhesives therapeutic use
- Abstract
Background: Wound healing after pectoral port implantation is a major factor determining the success or failure of the procedure. Infection and wound dehiscence can endanger the functionality of the port system and impede chemotherapy. The cosmetic result is important for patient satisfaction as well., Methods: From August 2015 to July 2017, adult patients with an indication for port implantation were entered into a prospective, randomized and controlled single-center study. The skin incision was closed either with tissue adhesive or with an intracutaneous suture. The primary endpoints were the total score of the scar evaluated by the patient and the investigator on the POSAS scale (Patient and Observer Scar Assessment Scale: 6 [normal skin] to 60 points), blinded assessment of photographic documentation by ten evaluating physicians, and the patient's reported quality of life. The calculation of case numbers was based only on the patients' overall POSAS assessment, which was tested for non-inferiority. The secondary endpoints were other complications (infection, dehiscence) and the duration of wound closure (trial registration number NCT02551510)., Results: 156 patients (60 ± 13 years, 64% women) participated in the study. The patient-assessed total POSAS score of tissue adhesive revealed non-inferiority to suturing (adhesive 11.7 ± 5.8 vs. suture 10.1 ± 4.0, p for non-inferiority <0.001). Both the investigators in their POSAS assessments and the blinded physician evaluators in their assessment of photographically documented wounds rated wound closure by suturing better than closure with tissue adhesive. No significant differences were found between groups with respect to quality of life or the frequency of wound infection or dehiscence., Conclusion: Closure of the upper cutaneous layer with tissue adhesive is a suitable and safe method of wound closure after port implantation.
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- 2021
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20. Hypomyelination and Congenital Cataract: Identification of a Novel likely pathogenic c.414+1G>A in FAM126A gene Variant.
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Troncoso M, Balut F, Witting S, Rubilar C, Carrera J, Cartes F, and Herrera L
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It is key to expand the differential diagnosis and consider possible genetic etiologies on a patient with congenital cataracts associated with clinical features, such as leukodystrophy or polyneuropathy., Competing Interests: None of the authors declare any conflict of interest., (© 2021 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.)
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- 2021
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21. Cytogenetic and immunohistochemical biomarker profiling of therapy-relevant factors in salivary gland carcinomas.
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Lemound J, Schenk M, Keller G, Stucki-Koch A, Witting S, Kreipe H, and Hussein K
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- Adult, Aged, Aged, 80 and over, Algorithms, DNA-Binding Proteins genetics, Endonucleases genetics, ErbB Receptors genetics, Female, Gene Amplification, Genes, erbB-2 genetics, Humans, Immunohistochemistry, In Situ Hybridization, Fluorescence, Male, Middle Aged, Proto-Oncogene Proteins c-met genetics, Receptor, ErbB-3 genetics, Receptors, Steroid genetics, Young Adult, Biomarkers, Tumor genetics, Carcinoma diagnosis, Carcinoma genetics, Salivary Gland Neoplasms diagnosis, Salivary Gland Neoplasms genetics
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Objectives: There is currently no established algorithm for the molecular profiling of therapy-relevant defects in salivary gland carcinomas (SGC). HER2 overexpression in a subfraction of SGC and low frequencies of EGFR mutations are known. Here, we established receptor and cell signalling profiles of 17 therapy-relevant factors and propose a molecular diagnostic algorithm for SGC., Materials and Methods: Formalin-fixed and paraffin-embedded tissue samples from SGC (n = 38) were analysed with immunohistochemistry and fluorescence in situ hybridisation (FISH)., Results: Two or more expressed receptors and/or receptor gene amplification were detectable in eight of 38 (21%) tumours: HER2 3+/AR 1+, HER3 gene amplification/AR 1+/EGFR 1+, ER 3+/AR 1+, EGFR 2+/PR 1+ and EGFR 2+/PR 1+/AR 1+. No FGFR1-3, MET, ALK1, ROS1, RET, BRAF nor VEGFA defects were detectable, and ERCC1 was not overexpressed. No PD1+ tumour-infiltrating T cells were detectable., Conclusion: Personalised therapy of patients with salivary gland carcinomas should include HER2 and EGFR signalling testing and, in negative cases, evaluation of rare potential target molecules. ERCC1 and PD1 do not appear to be reliable markers for the decision for or against chemotherapy or immunotherapy, respectively., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
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- 2016
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22. [Effect of supplementation with a single dose of vitamin D in children with cerebral palsy. Preliminary randomised controlled study].
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Le Roy C, Meier M, Witting S, Pérez-Bravo F, Solano C, and Castillo-Durán C
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- Adolescent, Alkaline Phosphatase blood, Calcium blood, Cerebral Palsy complications, Child, Child, Preschool, Chile, Female, Humans, Male, Phosphates blood, Prospective Studies, Vitamin D administration & dosage, Vitamin D Deficiency etiology, Cerebral Palsy drug therapy, Dietary Supplements, Vitamin D analogs & derivatives, Vitamin D Deficiency drug therapy
- Abstract
Introduction: Children with cerebral palsy (CP) have an increased risk of vitamin D (VD) deficiency. Although there are many studies on VD and CP, there is limited information about VD supplementation in these patients., Objective: To evaluate the effect of supplementation with a single dose of VD on the plasma concentrations of 25-hydroxy-vitamin-D (25OHD) in children with CP., Patients and Method: Prospective-randomised-controlled-trial, including 30 Chilean children (19 males) with CP, median age 9.9 years (6.2-13.5). Clinical and biochemical variables including 25OHD, were recorded (time 0 and 8 weeks). Patients were allocated to the supplemented (S) group receiving 100,000 IU oral D3 at baseline, and compared with the placebo (P) group., Results: Among clinical features are highlighted: gastrostomy (60%), underweight (30%), bed-ridden (93.3%), antiepileptic drugs (70%), and 43.3% used VD metabolism inducing antiepileptics. Baseline biochemical measurements were normal. The 25OHD was insufficient in 4/30 and deficient in 6/30. 25OHD levels were not associated with the variables studied. Eight patients completed the study in the S group, and 10 in P group. The placebo and supplementation groups had no significant difference in baseline variables. Serum calcium, phosphate, and alkaline phosphatase levels at 8 weeks were normal in both groups, with no statistically significant differences. 25OHD in the P group was normal in 6/10, and insufficient+deficient in 4/10, and the S group was normal in all (8/8) (exact Fisher test P=.07)., Conclusions: A single dose of 100,000 IU VD could normalise the concentrations of 25OHD after 8 weeks of supplementation in Children with CP, but more studies are required to confirm these results., (Copyright © 2015 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.)
- Published
- 2015
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23. Hypoxia Induces Mesenchymal Gene Expression in Renal Tubular Epithelial Cells: An in vitro Model of Kidney Transplant Fibrosis.
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Zell S, Schmitt R, Witting S, Kreipe HH, Hussein K, and Becker JU
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Background: The development of interstitial fibrosis and tubular atrophy is a common complication after kidney transplantation and is associated with reduced long-term outcome. The hallmark of tubulointerstitial fibrosis is an increase in extracellular matrix resulting from exaggerated activation of fibroblasts/myofibroblasts, and tubular atrophy is characterized by a decrease in tubular diameter and loss of function. Atrophic epithelial cells may undergo epithelial-to-mesenchymal transition (EMT) with potential differentiation into interstitial fibroblasts. One potential driver of EMT in developing interstitial fibrosis and tubular atrophy is chronic hypoxia., Methods: The expression of 46 EMT-related genes was analyzed in an in vitro hypoxia model in renal proximal tubular epithelial cells (RPTEC). Furthermore, the expression of 342 microRNAs (miR) was evaluated in hypoxic culture conditions., Results: Hypoxic RPTEC expressed markers of a more mesenchymal phenotype and showed an increased expression of matrix metalloproteinase-2 (MMP2). MMP2 expression in RPTEC correlated inversely with a decreased expression of miR-124, which was found to have a putative binding site for the MMP2 transcript. Overexpression of miR-124 inhibited MMP2 protein translation. Hypoxia was associated with increased migration/proliferation of RPTEC which was reversed by miR-124., Conclusions: These results indicate that hypoxia promotes a mesenchymal and migratory phenotype in renal epithelial cells, which is associated with increased MMP2 expression. Hypoxia-dependent MMP2 expression is regulated via a reduced transcription of miR-124. Overexpression of miR-124 antagonizes hypoxia-induced cell migration. Further research is needed to elucidate the functional role of miR-124 and MMP2 in the development of fibrosis in renal transplant degeneration.
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- 2013
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24. Neuronal ceroid lipofuscinosis type CLN2: a new rationale for the construction of phenotypic subgroups based on a survey of 25 cases in South America.
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Kohan R, Carabelos MN, Xin W, Sims K, Guelbert N, Cismondi IA, Pons P, Alonso GI, Troncoso M, Witting S, Pearce DA, Dodelson de Kremer R, Oller-Ramírez AM, and Noher de Halac I
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- Adolescent, Adult, Alleles, Alternative Splicing, Aminopeptidases metabolism, Argentina, Child, Child, Preschool, Computational Biology, Dipeptidyl-Peptidases and Tripeptidyl-Peptidases metabolism, Female, Humans, Introns, Male, Microscopy, Electron, Transmission, Mutation, Neuronal Ceroid-Lipofuscinoses pathology, Pedigree, Prospective Studies, Reproducibility of Results, Retrospective Studies, Serine Proteases metabolism, South America, Tripeptidyl-Peptidase 1, Young Adult, Aminopeptidases genetics, Dipeptidyl-Peptidases and Tripeptidyl-Peptidases genetics, Neuronal Ceroid-Lipofuscinoses enzymology, Neuronal Ceroid-Lipofuscinoses genetics, Phenotype, Serine Proteases genetics
- Abstract
Tripeptidyl-peptidase 1 (TPP1) null or residual activity occurs in neuronal ceroid lipofuscinosis (NCL) with underlying TPP1/CLN2 mutations. A survey of 25 South American CLN2 affected individuals enabled the differentiation of two phenotypes: classical late-infantile and variant juvenile, each in approximately 50% of patients, with residual TPP1 activity occurring in approximately 32%. Each individual was assigned to one of three subgroups: (I) n=11, null TPP1 activity in leukocytes; (II) n=8, residual TPP1 activity of 0.60-15.85 nmol/h/mg (nr 110-476); (III) n=6, activity not measured in leukocytes. Curvilinear bodies (CB) appeared in almost all studied CLN2 subjects; the only exceptions occurred in cases of subgroup II: two individuals had combined CBs/fingerprints (FPs), and one case had pure FPs. There were 15 mutations (4 first published in this paper, 3 previously observed in South America by our group, and 8 previously observed by others). In subgroup I, mutations were either missense or nonsense; in subgroups II and III, mutations prevailed at the non-conserved intronic site, c.887-10A>G (intron 7), and to a lesser extent at c.89+5G>C (intron 2), in heterozygous combinations. Grouping phenotypically and genetically known individuals on the basis of TPP1 activity supported the concept that residual enzyme activity underlies a protracted disease course. The prevalence of intronic mutations at non-conserved sites in subgroup II individuals indicates that some alternative splicing might allow some residual TPP1 activity., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
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25. Constitutive expression of short hairpin RNA in vivo triggers buildup of mature hairpin molecules.
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Ahn M, Witting SR, Ruiz R, Saxena R, and Morral N
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- Animals, Biomarkers metabolism, Blotting, Northern, Blotting, Western, Cells, Cultured, Fatty Acid-Binding Proteins genetics, Gene Expression Profiling, Hepatocytes cytology, Hepatocytes metabolism, Liver pathology, Male, Mice, Mice, Inbred C57BL, Neoplasm Proteins genetics, Oligonucleotide Array Sequence Analysis, RNA, Messenger genetics, RNA, Small Interfering genetics, Real-Time Polymerase Chain Reaction, Sterol Regulatory Element Binding Protein 1 genetics, Transduction, Genetic, Fatty Acid-Binding Proteins antagonists & inhibitors, Gene Silencing, Genetic Vectors administration & dosage, Liver metabolism, Neoplasm Proteins antagonists & inhibitors, RNA Interference, RNA, Small Interfering metabolism, Sterol Regulatory Element Binding Protein 1 antagonists & inhibitors
- Abstract
RNA interference (RNAi) has become the cornerstone technology for studying gene function in mammalian cells. In addition, it is a promising therapeutic treatment for multiple human diseases. Virus-mediated constitutive expression of short hairpin RNA (shRNA) has the potential to provide a permanent source of silencing molecules to tissues, and it is being devised as a strategy for the treatment of liver conditions such as hepatitis B and hepatitis C virus infection. Unintended interaction between silencing molecules and cellular components, leading to toxic effects, has been described in vitro. Despite the enormous interest in using the RNAi technology for in vivo applications, little is known about the safety of constitutively expressing shRNA for multiple weeks. Here we report the effects of in vivo shRNA expression, using helper-dependent adenoviral vectors. We show that gene-specific knockdown is maintained for at least 6 weeks after injection of 1 × 10(11) viral particles. Nonetheless, accumulation of mature shRNA molecules was observed up to weeks 3 and 4, and then declined gradually, suggesting the buildup of mature shRNA molecules induced cell death with concomitant loss of viral DNA and shRNA expression. No evidence of well-characterized innate immunity activation (such as interferon production) or saturation of the exportin-5 pathway was observed. Overall, our data suggest constitutive expression of shRNA results in accumulation of mature shRNA molecules, inducing cellular toxicity at late time points, despite the presence of gene silencing.
- Published
- 2011
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26. Hematopoietic stem/progenitor cells, generation of induced pluripotent stem cells, and isolation of endothelial progenitors from 21- to 23.5-year cryopreserved cord blood.
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Broxmeyer HE, Lee MR, Hangoc G, Cooper S, Prasain N, Kim YJ, Mallett C, Ye Z, Witting S, Cornetta K, Cheng L, and Yoder MC
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- Animals, Colony-Forming Units Assay, Endothelial Cells cytology, Fetal Blood transplantation, Hematopoietic Stem Cell Transplantation, Humans, In Vitro Techniques, Induced Pluripotent Stem Cells transplantation, Infant, Newborn, Interleukin Receptor Common gamma Subunit deficiency, Interleukin Receptor Common gamma Subunit genetics, Lymphocyte Activation, Mice, Mice, Inbred NOD, Mice, Knockout, Mice, SCID, T-Lymphocyte Subsets cytology, T-Lymphocyte Subsets immunology, Time Factors, Transplantation, Heterologous, Blood Preservation, Cryopreservation, Fetal Blood cytology, Hematopoietic Stem Cells cytology, Induced Pluripotent Stem Cells cytology
- Abstract
Cryopreservation of hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) is crucial for cord blood (CB) banking and transplantation. We evaluated recovery of functional HPC cryopreserved as mononuclear or unseparated cells for up to 23.5 years compared with prefreeze values of the same CB units. Highly efficient recovery (80%-100%) was apparent for granulocyte-macrophage and multipotential hematopoietic progenitors, although some collections had reproducible low recovery. Proliferative potential, response to multiple cytokines, and replating of HPC colonies was extensive. CD34(+) cells isolated from CB cryopreserved for up to 21 years had long-term (≥ 6 month) engrafting capability in primary and secondary immunodeficient mice reflecting recovery of long-term repopulating, self-renewing HSCs. We recovered functionally responsive CD4(+) and CD8(+) T lymphocytes, generated induced pluripotent stem (iPS) cells with differentiation representing all 3 germ cell lineages in vitro and in vivo, and detected high proliferative endothelial colony forming cells, results of relevance to CB biology and banking.
- Published
- 2011
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27. Phosphatidylserine externalization in sickle red blood cells: associations with cell age, density, and hemoglobin F.
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Yasin Z, Witting S, Palascak MB, Joiner CH, Rucknagel DL, and Franco RS
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- Adult, Erythrocyte Aging, Erythrocyte Membrane metabolism, Erythrocyte Membrane ultrastructure, Erythrocytes ultrastructure, Fetal Hemoglobin analysis, Humans, Phosphatidylserines analysis, Receptors, Transferrin analysis, Reticulocytes chemistry, Reticulocytes ultrastructure, Water metabolism, Anemia, Sickle Cell blood, Erythrocytes chemistry, Phosphatidylserines metabolism
- Abstract
Phosphatidylserine (PS) is normally confined to the cytoplasmic leaflet of the red blood cell (RBC) membrane, but some sickle RBCs expose PS in the outer leaflet (PS+ cells). This study examined the relationships among PS externalization, fetal hemoglobin content, hydration state, and cell age. Sickle RBCs exhibit a wide range of PS externalization. Those with low-level exposure (type 1 PS+) include many young transferrin-receptor-positive (TfR+) cells. This is not specific for sickle cell disease because many nonsickle TfR+ cells are also PS+. RBCs with higher PS exposure (type 2 PS+) appear to be more specific for sickle cell disease. Their formation is most likely sickling dependent because type 2 PS+ dense sickle cells have a lower percentage of fetal hemoglobin (HbF) than PS- cells in the same density fraction (1.7 vs 2.9; n = 8; P <.01). In vivo experiments using biotin-labeled sickle cells showed a sharp decrease in the percentage of circulating, labeled PS+ cells in the first 24 hours after reinfusion. This decrease was confined to type 1 PS+ cells and was thus consistent with the reversal of PS exposure in very young cells. As the labeled cells aged in the circulation, the percentages of type 1 and type 2 PS+ cells increased. These studies indicate that PS externalization in sickle cells may be low level, as observed in many immature cells, or high level, which is associated with dehydration and appears to be more specific for sickle RBCs.
- Published
- 2003
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