23 results on '"Prada C"'
Search Results
2. A Reduced-Order Approach of Distributed Parameter Models Using Proper Orthogonal Decomposition
- Author
-
Valbuena, M., primary, Sarabia, D., additional, and de Prada, C., additional
- Published
- 2011
- Full Text
- View/download PDF
3. Hybrid control of a mixed continuous-batch process
- Author
-
de Prada, C., primary, Cristea, S., additional, Sarabia, D., additional, and Colmenares, W., additional
- Published
- 2004
- Full Text
- View/download PDF
4. AN EXPERT SYSTEM FOR A CONTROL COORDINATION PROBLEM
- Author
-
Alonso, C., primary, Prada, C., additional, Rico, J.A., additional, and Hernandez, F., additional
- Published
- 1992
- Full Text
- View/download PDF
5. Predictors of elephant poaching in a wildlife crime hotspot: The Ruvuma landscape of southern Tanzania and northern Mozambique
- Author
-
Martin Reinhardt Nielsen, Prada. C., Neil D. Burgess, Noelia Zafra-Calvo, Jorge M. Lobo, Natural Environment Research Council (UK), and Danish National Research Foundation
- Subjects
0106 biological sciences ,Game reserve ,Wildlife ,010603 evolutionary biology ,01 natural sciences ,African elephant ,biology.animal ,Hotspot (geology) ,Community management ,Nature and Landscape Conservation ,Ecology ,biology ,Agroforestry ,Water availability ,010604 marine biology & hydrobiology ,Poaching ,biology.organism_classification ,East Africa ,Protected areas ,Tanzania ,Geography ,Protected area - Abstract
Understanding the spatial distribution of elephant carcasses in relation to ecological characteristics and human activities is critical to developing targeted management strategies for reducing poaching. We employ a spatial modelling approach to quantify the relative contribution of multiple climatic, ecological, human and protected area management predictors of the number of elephant carcasses in a recognized poaching hotspot: the Ruvuma landscape of northern Mozambique and southern Tanzania. This includes the Niassa Reserve in the south and the Selous Game Reserve in the north. In Mozambique, the number of elephant carcasses is positively associated with State-managed protected areas such as Niassa Reserve, but particularly with environmental variables including low rainfall and high temperatures. In Tanzania, elephant carcasses are positively associated with community-managed sites. A strong focus on effective management of protected areas in the Ruvuma landscape is crucial to reducing the killing of elephants., This work builds partially on the research project ‘Poverty and ecosystem Impacts of Tanzania’s wildlife Management Areas’ (“PIMA”), funded by the Ecosystem Services for Poverty Alleviation (ESPA) programme (NE/L00139X/1), itself funded by UK’s Department for International Development, Economic and Social Research Council and Natural Environment Research Council. N.Z-C. and N.B. acknowledge the Danish National Research Foundation for funding for the Center for Macroecology, Evolution and Climate; grant number DNRF96.
- Published
- 2018
6. Predictors of elephant poaching in a wildlife crime hotspot: The Ruvuma landscape of southern Tanzania and northern Mozambique
- Author
-
Natural Environment Research Council (UK), Danish National Research Foundation, Zafra-Calvo, Noelia, Lobo, Jorge M., Prada. C., Nielsen, M. R., Burgess, Neil D., Natural Environment Research Council (UK), Danish National Research Foundation, Zafra-Calvo, Noelia, Lobo, Jorge M., Prada. C., Nielsen, M. R., and Burgess, Neil D.
- Abstract
Understanding the spatial distribution of elephant carcasses in relation to ecological characteristics and human activities is critical to developing targeted management strategies for reducing poaching. We employ a spatial modelling approach to quantify the relative contribution of multiple climatic, ecological, human and protected area management predictors of the number of elephant carcasses in a recognized poaching hotspot: the Ruvuma landscape of northern Mozambique and southern Tanzania. This includes the Niassa Reserve in the south and the Selous Game Reserve in the north. In Mozambique, the number of elephant carcasses is positively associated with State-managed protected areas such as Niassa Reserve, but particularly with environmental variables including low rainfall and high temperatures. In Tanzania, elephant carcasses are positively associated with community-managed sites. A strong focus on effective management of protected areas in the Ruvuma landscape is crucial to reducing the killing of elephants.
- Published
- 2018
7. A COMPUTER SYSTEM FOR DESIGN AND TRAINING ON ADVANCED CONTROL TECHNIQUES
- Author
-
Vega, P., primary, Prada, C., additional, and Prada, F., additional
- Published
- 1987
- Full Text
- View/download PDF
8. DYNAMIC SIMULATION OF A MULTIPLE-EFFECT EVAPORATION STATION
- Author
-
Prada, C., primary, Villar, E., additional, and Aleixandre, V., additional
- Published
- 1987
- Full Text
- View/download PDF
9. A Study on the Efficacy and Safety of Pipeline Shield Stents and Nonmodified Surface Flow-Diverting Stents in Patients with Intracranial Aneurysms.
- Author
-
García-Núñez J, D Vera D, Ortiz AF, Rodríguez A, Lara JJ, Gomez MJ, Serrano-Gómez S, Reyes A, Ferreira-Prada C, Galvis-Méndez M, Vargas-Pérez O, and Mantilla-García DE
- Subjects
- Humans, Retrospective Studies, Treatment Outcome, Stents adverse effects, Intracranial Aneurysm complications, Embolization, Therapeutic, Endovascular Procedures
- Abstract
Background: Few studies have compared the Pipeline Shield stents with previous generations of flow-diverting stents (FDSs) for the treatment of unruptured intracranial aneurysms. This study aimed to evaluate the efficacy and safety of Pipeline Shield stents and FDSs without modified surfaces., Methods: The present evaluation is a retrospective cohort study of patients endovascularly treated with Pipeline Shield stents or FDSs without modified surfaces for unruptured intracranial aneurysms between January 2014 and June 2022. The data analyzed were obtained from the anonymized database of our institution's interventional radiology service., Results: A total of 147 patients with 155 unruptured intracranial aneurysms were included. Of the 155 aneurysms, 96 were treated with Pipeline Shield stents and 59 with FDSs without modified surfaces. The aneurysms treated with Pipeline Shield stents had higher 6-month (O'Kelly-Marotta [OKM] D; 87.5% vs. 71.4%; P = 0.025) and 1-year (OKM D; 82.5% vs. 63.0%; P = 0.047) occlusion rates than the aneurysms treated using FDSs without modified surfaces. No differences between the devices were found at the 1-year follow-up in the incidence of ischemic stroke (P = 0.939) or hemorrhagic complications (P = 0.559)., Conclusions: Pipeline Shield stents demonstrated superior complete occlusion rates (OKM D) at both the 6-month and the 1-year follow-up assessments compared with nonmodified surface FDSs. No significant differences were found in the safety profiles between the 2 types of stents with regard to thromboembolic complications and ischemic events. Further research with larger study populations is necessary to validate these findings., (Copyright © 2024 Elsevier Inc. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
10. A decade of population genetics studies of scleractinian corals: A systematic review.
- Author
-
Alvarado-Cerón V, Muñiz-Castillo AI, León-Pech MG, Prada C, and Arias-González JE
- Subjects
- Animals, Ecosystem, Australia, Coral Reefs, Genetics, Population, Anthozoa genetics
- Abstract
Coral reefs are the most diverse marine ecosystems. However, coral cover has decreased worldwide due to natural disturbances, climate change, and local anthropogenic drivers. In recent decades, various genetic methods and molecular markers have been developed to assess genetic diversity, structure, and connectivity in different coral species to determine the vulnerability of their populations. This review aims to identify population genetic studies of scleractinian corals in the last decade (2010-2020), and the techniques and molecular markers used. Bibliometric analysis was conducted to identify journals and authors working in this field. We then calculated the number of genetic studies by species and ecoregion based on data obtained from 178 studies found in Scopus and Web of Science. Coral Reefs and Molecular Ecology were the main journals published population genetics studies, and microsatellites are the most widely used molecular markers. The Caribbean, Australian Barrier Reef, and South Kuroshio in Japan are among the ecoregions with the most population genetics data. In contrast, we found limited information about the Coral Triangle, a region with the highest biodiversity and key to coral reef conservation. Notably, only 117 (out of 1500 described) scleractinian coral species have genetic studies. This review emphasizes which coral species have been studied and highlights remaining gaps and locations where such data is critical for coral conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
11. MRPA-independent mechanisms of antimony resistance in Leishmania infantum.
- Author
-
Douanne N, Wagner V, Roy G, Leprohon P, Ouellette M, and Fernandez-Prada C
- Subjects
- ATP-Binding Cassette Transporters drug effects, Animals, Antiprotozoal Agents pharmacology, Dogs, Drug Resistance genetics, Genes, Protozoan, Humans, Leishmaniasis drug therapy, Membrane Transport Proteins genetics, Multidrug Resistance-Associated Protein 2, Mutation, Protozoan Proteins genetics, Serine O-Acetyltransferase drug effects, Whole Genome Sequencing, ATP-Binding Cassette Transporters genetics, Antimony pharmacology, Leishmania infantum drug effects, Leishmania infantum genetics, Serine O-Acetyltransferase genetics
- Abstract
Control of both human and canine leishmaniasis is based on a very short list of chemotherapeutic agents, headed by antimonial derivatives (Sb). The utility of these molecules is severely threatened by high rates of drug resistance. The ABC transporter MRPA is one of the few key Sb resistance proteins described to date, whose role in detoxification has been thoroughly studied in Leishmania parasites. Nonetheless, its rapid amplification during drug selection complicates the discovery of other mechanisms potentially involved in Sb resistance. In this study, stepwise drug-resistance selection and next-generation sequencing were combined in the search for novel Sb-resistance mechanisms deployed by parasites when MRPA is abolished by targeted gene disruption. The gene mrpA is not essential in L. infantum, and its disruption leads to an Sb hypersensitive phenotype in both promastigotes and amastigotes. Five independent mrpA
-/- mutants were selected for antimony resistance. These mutants displayed major changes in their ploidy, as well as extrachromosomal linear amplifications of the subtelomeric region of chromosome 23, which includes the genes coding for ABCC1 and ABCC2. Overexpression of ABCC2, but not of ABCC1, resulted in increased Sb tolerance in the mrpA-/- mutant. SNP analyses revealed three different heterozygous mutations in the gene coding for a serine acetyltransferase (SAT) involved in de novo cysteine synthesis in Leishmania. Overexpression of satQ390K , satG321R and satG325R variants led to a 2-3.2 -fold increase in Sb resistance in mrpA-/- parasites. Only satG321R and satG325R induced increased Sb resistance in wild-type parasites. These results reinforce and expand knowledge on the complex nature of Sb resistance in Leishmania parasites., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)- Published
- 2020
- Full Text
- View/download PDF
12. Physical outcome measures: The role of strength and range of motion in orthopaedic research.
- Author
-
Marcano-Fernández F, Prada C, and Johal H
- Subjects
- Humans, Observer Variation, Orthopedic Procedures, Reproducibility of Results, Rotation, Muscle Strength physiology, Orthopedics methods, Range of Motion, Articular physiology
- Abstract
Outcome measures are the indispensable mean through which different interventions are compared in research. The increase in volume that orthopaedic research has experienced in the last years has provided an extensive list of outcomes to choose from. Historically, attention has been focused mainly in morbidity as well as physician reported clinical outcomes, however there is a trend towards the use of patient reported outcomes. We intent to review the inherent characteristics and current applicability of two of the most representative physical outcome measures used in orthopaedics: Range of Motion (ROM) and Strength., Competing Interests: Declaration of Competing Interest The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2019. Published by Elsevier Ltd.)
- Published
- 2020
- Full Text
- View/download PDF
13. The development of sarcoidosis in patients receiving daclizumab: A case series from multiple clinical trials.
- Author
-
Judson MA, Elicker BM, Colby TV, Kwon S, de Windt E, Chalkias S, Prada C, Smirnakis K, and Singhal P
- Subjects
- Adult, Daclizumab administration & dosage, Daclizumab therapeutic use, Female, Humans, Immunosuppressive Agents administration & dosage, Immunosuppressive Agents therapeutic use, Incidence, Lung Diseases chemically induced, Lung Diseases pathology, Male, Middle Aged, Multiple Sclerosis complications, Pharmacovigilance, Sarcoidosis diagnostic imaging, Sarcoidosis epidemiology, Skin Diseases chemically induced, Skin Diseases pathology, Daclizumab adverse effects, Immunosuppressive Agents adverse effects, Multiple Sclerosis drug therapy, Sarcoidosis chemically induced, Sarcoidosis pathology
- Abstract
Introduction: Several drugs have been associated with druginduced sarcoidosis-like reactions (DISRs) that are clinically indistinguishable from sarcoidosis. Daclizumab is a humanized monoclonal IgG1 antibody that binds to CD25 that has been studied for the treatment of multiple sclerosis (MS). During MS clinical trials of daclizumab, 12 subjects developed clinical conditions potentially consistent with sarcoidosis. Therefore, an independent adjudication committee of individuals with expertise in sarcoidosis was organized to determine the likelihood of these cases representing sarcoidosis., Methods: The adjudication committee consisted of a pulmonologist, pathologist, and radiologist with clinical experience in sarcoidosis. The committee had access to the subjects' laboratory data, narratives of all suspect adverse reaction reports, radiographic imaging and histology from biopsies. A priori, a grading system was developed to determine criteria to establish the likelihood that the patient had developed sarcoidosis., Results: The adjudication confirmed sarcoidosis in 11/12 subjects. The committee's decisions were unanimous in all cases. Biopsies were available in 7/11 of these. In the 4 subjects who did not have a biopsy, they all had presentations, clinical findings, and/or laboratory findings that were highly specific for sarcoidosis. Alternative causes for these clinical findings were reasonably excluded in all cases. The lung (8/11) and skin (6/11) were the most common organs involved. The mean daclizumab dose given when signs or symptoms of sarcoidosis occurred was 5413 ± 2704 mg and the median time from first daclizumab dose was 996 days. The incidence rate of developing sarcoidosis in those participating in these daclizumab trials was 154/100,000 patient-years compared with incidence rates of sarcoidosis in the United States of 3.2-17.8/100,000/year. These data suggest that these sarcoidosis cases may have represented DISRs related to daclizumab therapy., Conclusions: Given the clinical presentation and subsequent evaluation of these 11 subjects, we suspect that they had DISRs from daclizumab., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
14. High-throughput identification and quantification of Haemonchus contortus in fecal samples.
- Author
-
Douanne N, Wagner V, Bélanger D, and Fernandez-Prada C
- Subjects
- Animals, Parasite Egg Count, Reproducibility of Results, Sheep, Sheep Diseases diagnosis, Feces parasitology, Haemonchus isolation & purification, High-Throughput Screening Assays veterinary, Sheep Diseases parasitology
- Abstract
Haemonchus contortus are gastrointestinal nematodes of the family Trichostrongylidae that naturally infect small ruminants while grazing, posing a risk to both animal health and farm profitability. Current diagnostics depend on exacting lab techniques, including manual egg counts and larval differentiation, all of which require time, effort, and specialized technicians. The goal of this study was to facilitate and accelerate the identification and quantification of H. contortus in fecal samples through the use of fluorescein-isothiocyanate peanut-agglutinin staining in order to allow automated detection using a 96-well microplate reader. Next, the model was to be validated using samples containing unknown quantities of eggs. Automated analysis of fluorescence emission of known quantities of H. contortus eggs confirmed an almost perfect linear correlation (r = 0.9984, p < 0.0001), indicating that this new approach can satisfactorily be used to quantify H. contortus eggs on a comparative fluorescence scale. As validation, clinical samples containing an unknown quantity of H. contortus eggs were then analyzed by comparing two methods: either Wisconsin Sugar Flotation (WSF) and McMaster counting followed by manual fluorescence microscopy, or WSF coupled with automated microplate reading. Pearson analysis revealed highly significant correlation between manual and automated methods (r = 0.9999, p < 0.0001), while Bland-Altman plots demonstrated excellent agreement between the two (bias = -0.817 ± 9.94 with 95% limits of agreement from -20.31 to 18.67). Overall, these results demonstrate that high-throughput screening fluorescence detection and quantification of H. contortus eggs is both accurate and rapid., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
15. High-throughput Cos-Seq screen with intracellular Leishmania infantum for the discovery of novel drug-resistance mechanisms.
- Author
-
Fernandez-Prada C, Sharma M, Plourde M, Bresson E, Roy G, Leprohon P, and Ouellette M
- Subjects
- Amphotericin B pharmacology, Animals, Antimony pharmacology, Antimony therapeutic use, CRISPR-Cas Systems, Cosmids, Gene Library, Leishmaniasis drug therapy, Life Cycle Stages drug effects, Life Cycle Stages genetics, Macrophages parasitology, Phosphorylcholine analogs & derivatives, Phosphorylcholine pharmacology, Phosphorylcholine therapeutic use, Antiprotozoal Agents pharmacology, Drug Resistance genetics, High-Throughput Nucleotide Sequencing, Leishmania infantum drug effects, Leishmania infantum genetics
- Abstract
Increasing drug resistance towards first line antimony-derived compounds has forced the introduction of novel therapies in leishmaniasis endemic areas including amphotericin B and miltefosine. However, their use is threatened by the emergence and spread of drug-resistant strains. In order to discover stage-dependent resistance genes, we have adapted the Cos-Seq approach through the introduction of macrophage infections in the pipeline. A L. infantum intracellular amastigote population complemented with a L. infantum cosmid library was submitted to increasing concentrations of miltefosine, amphotericin B and pentavalent antimonials in experimental infections of THP-1 cells. For each step of selection, amastigotes were extracted and cosmids were isolated and submitted to next-generation sequencing, followed by subsequent gene-enrichment analyses. Cos-Seq screen in amastigotes revealed four highly enriched loci for antimony, five for miltefosine and one for amphotericin B. Of these, a total of seven cosmids were recovered and tested for resistance in both promastigotes and amastigotes. Candidate genes within the pinpointed genomic regions were validated using single gene overexpression in wild-type parasites and/or gene disruption by means of a CRISPR-Cas9-based approach. This led to the identification and validation of a stage-independent antimony-resistance gene (LinJ.06.1010) coding for a putative leucine rich repeat protein and a novel amastigote-specific miltefosine-resistance gene (LinJ.32.0050) coding for a member of the SEC13 family of WD-repeat proteins. This study further reinforces the power of Cos-Seq approach to discover novel drug-resistance genes, some of which are life-stages specific., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
16. Multiple Myeloma in Pregnancy--A Review of the Literature and a Case Series.
- Author
-
Jurczyszyn A, Olszewska-Szopa M, Vesole AS, Vesole DH, Siegel DS, Richardson PG, Paba-Prada C, Callander NS, Huras H, and Skotnicki AB
- Subjects
- Adult, Combined Modality Therapy, Diagnostic Imaging, Fatal Outcome, Female, Humans, Neoplasm Staging, Pregnancy, Treatment Outcome, Multiple Myeloma diagnosis, Multiple Myeloma therapy, Pregnancy Complications, Neoplastic
- Abstract
Multiple myeloma (MM) typically affects older patients with a median age at diagnosis of 67 to 70 years and only 3% of cases are diagnosed before the age of 40. Moreover, MM is more common in men. Therefore, pregnancy rarely occurs in patients with MM and only 37 cases of MM in pregnancy have been reported in the literature. Herein we report an additional 5 cases. The diagnosis of MM might be problematic in this context because some of the symptoms and signs, such as back pain and anemia, can be attributed to pregnancy. Furthermore, if the patient wishes to continue her pregnancy, therapeutic options are currently limited. The list of agents that can be safely administered in pregnant women includes glucocorticoids. Moreover, any continuation of pregnancy has obvious long-term psychosocial repercussions for the patient and her family because of the currently incurable nature of MM. The reported cases of MM in pregnancy represent a spectrum of clinical manifestations. The selection of efficacious and safe treatments is challenging, especially if continuation of pregnancy is desired. Although some authors postulate that pregnancy might lead to progression of MM, data are limited and no consensus on this point has been reached., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
17. Drug resistance analysis by next generation sequencing in Leishmania.
- Author
-
Leprohon P, Fernandez-Prada C, Gazanion É, Monte-Neto R, and Ouellette M
- Subjects
- Antiprotozoal Agents pharmacology, Drug Resistance, Genetic Variation, Leishmania drug effects, Leishmania genetics, Nucleic Acid Amplification Techniques methods
- Abstract
The use of next generation sequencing has the power to expedite the identification of drug resistance determinants and biomarkers and was applied successfully to drug resistance studies in Leishmania. This allowed the identification of modulation in gene expression, gene dosage alterations, changes in chromosome copy numbers and single nucleotide polymorphisms that correlated with resistance in Leishmania strains derived from the laboratory and from the field. An impressive heterogeneity at the population level was also observed, individual clones within populations often differing in both genotypes and phenotypes, hence complicating the elucidation of resistance mechanisms. This review summarizes the most recent highlights that whole genome sequencing brought to our understanding of Leishmania drug resistance and likely new directions.
- Published
- 2014
- Full Text
- View/download PDF
18. Trypanosomatids topoisomerase re-visited. New structural findings and role in drug discovery.
- Author
-
Balaña-Fouce R, Alvarez-Velilla R, Fernández-Prada C, García-Estrada C, and Reguera RM
- Abstract
The Trypanosomatidae family, composed of unicellular parasites, causes severe vector-borne diseases that afflict human populations worldwide. Chagas disease, sleeping sickness, as well as different sorts of leishmaniases are amongst the most important infectious diseases produced by Trypanosoma cruzi, Trypanosoma brucei and Leishmania spp., respectively. All these infections are closely related to weak health care services in low-income populations of less developed and least economically developed countries. Search for new therapeutic targets in order to hit these pathogens is of paramount priority, as no effective vaccine is currently in use against any of these parasites. Furthermore, present-day chemotherapy comprises old-fashioned drugs full of important side effects. Besides, they are prone to produce tolerance and resistance as a consequence of their continuous use for decades. DNA topoisomerases (Top) are ubiquitous enzymes responsible for solving the torsional tensions caused during replication and transcription processes, as well as in maintaining genomic stability during DNA recombination. As the inhibition of these enzymes produces cell arrest and triggers cell death, Top inhibitors are among the most effective and most widely used drugs in both cancer and antibacterial therapies. Top relaxation and decatenation activities, which are based on a common nicking-closing cycle involving one or both DNA strands, have been pointed as a promising drug target. Specific inhibitors that bind to the interface of DNA-Top complexes can stabilize Top-mediated transient DNA breaks. In addition, important structural differences have been found between Tops from the Trypanosomatidae family members and Tops from the host. Such dissimilarities make these proteins very interesting for drug design and molecular intervention. The present review is a critical update of the last findings regarding trypanosomatid's Tops, their new structural features, their involvement both in the physiology and virulence of these parasites, as well as their use as promising targets for drug discovery.
- Published
- 2014
- Full Text
- View/download PDF
19. Amyloid beta protein starting pyroglutamate at position 3 is a major component of the amyloid deposits in the Alzheimer's disease brain.
- Author
-
Harigaya Y, Saido TC, Eckman CB, Prada CM, Shoji M, and Younkin SG
- Subjects
- Aged, Aged, 80 and over, Female, Humans, Male, Plaque, Amyloid metabolism, Alzheimer Disease metabolism, Amyloid beta-Peptides metabolism, Brain metabolism, Peptide Fragments metabolism, Pyrrolidonecarboxylic Acid metabolism
- Abstract
The amyloid beta protein (Abeta) deposited in the Alzheimer's disease (AD) brain is heterogeneous at both its amino and carboxyl termini. Recent studies of the genetic forms of AD indicate that the aggregation and deposition of Abeta42 may be a common initiating event in all forms of AD. Here, we analyzed the amino termini of the Abeta species deposited in the AD brain, focusing specifically on species with amino-terminal pyroglutamate at position 3 (Abeta3(pE)). Immunocytochemical analysis of AD brains with an antibody specific for Abeta3(pE) confirmed that these species deposit in blood vessels and senile plaques. Using specific sandwich ELISAs, we determined the amounts of Abeta3(pE)-40 and Abeta3(pE)-42(43) in AD brain compared with other forms. This analysis showed that Abeta3(pE)-40 is closely correlated with the extent of Abeta deposition in blood vessels, whereas Abeta3(pE)-42(43) is not. In addition, Abeta3(pE)-42(43) is an important component of the Abeta deposited in senile plaques of the AD brain, constituting approximately 25% of the total Abeta42(43). In vitro comparison of Abeta1-42 and Abeta3(pE)-42 showed that Abeta3(pE)-42 is highly prone to oligomerization. These findings suggest that Abeta3(pE)-42 may be particularly important in AD pathogenesis., (Copyright 2000 Academic Press.)
- Published
- 2000
- Full Text
- View/download PDF
20. Cryopreserved arterial homografts: preliminary results in infrageniculate arterial reconstructions.
- Author
-
Alonso M, Segura RJ, Prada C, Caeiro S, Cachaldora JA, Diaz E, Luján S, Cal L, and Vidal J
- Subjects
- Aged, Follow-Up Studies, Humans, Retrospective Studies, Time Factors, Transplantation, Homologous, Vascular Surgical Procedures, Arteries transplantation, Cryopreservation, Ischemia surgery, Leg blood supply
- Abstract
The aim of this report is to present our preliminary experience using cryopreserved arterial homografts in below-knee revascularization. We carried out a retrospective study at the Public Health Hospital of the Servicio Galego da Saude (SERGAS) from October 1995 to March 1997 in which cryopreserved arterial homografts were used for revascularization of 17 lower limbs in 16 patients. The clinical indications were limb-threatening ischemia in 15 lower extremities (7 with rest pain and 8 with ischemic ulcers or gangrene), and large aneurysms of femoropopliteal arteries in 2. In addition, 75% of the patients had undergone previous surgical procedures for revascularization on the involved extremity. No patient had a suitable greater saphenous vein in the ipsilateral extremity and all patients required a below-knee arterial reconstruction procedure. There was just one runoff vessel in 11 of 17 extremities (65%). A histological exam was performed in four patients who died (1 case) or had homograft-related complications (3 cases). The results of this study indicated that cryopreserved arterial homografts could be a promising alternative when below-knee revascularization is required in patients lacking suitable greater saphenous vein, especially in those with limited life expectancy, but despite early acceptable results, many aspects must be clarified. Close follow-up is mandatory.
- Published
- 1999
- Full Text
- View/download PDF
21. Accumulation of beta-amyloid fibrils in pancreas of transgenic mice.
- Author
-
Kawarabayashi T, Shoji M, Sato M, Sasaki A, Ho L, Eckman CB, Prada CM, Younkin SG, Kobayashi T, Tada N, Matsubara E, Iizuka T, Harigaya Y, Kasai K, and Hirai S
- Subjects
- Amyloid beta-Peptides genetics, Animals, Base Sequence, Blotting, Northern, Blotting, Western, Cytomegalovirus genetics, Enzyme-Linked Immunosorbent Assay, Humans, Immunohistochemistry, Mice, Mice, Transgenic, Microscopy, Electron, Molecular Sequence Data, Neurofibrils ultrastructure, Pancreas ultrastructure, Polymerase Chain Reaction, Transgenes, Amyloid beta-Peptides metabolism, Neurofibrils metabolism, Pancreas metabolism
- Abstract
Some forms of familial Alzheimer's disease are caused by mutations in the amyloid beta protein precursor (beta APP), and there is excellent evidence that these mutations foster amyloid deposition by increasing secretion of total amyloid beta protein (A beta) or the highly amyloidogenic A beta 1-42 form. These observations provide a powerful rationale for developing an animal model of AD by generating transgenic mice in which cerebral amyloid deposition is induced by A beta overproduction. To produce substantial A beta in vivo, we generated mice expressing the transgene of signal peptide and 99 residues of carboxyl-terminal fragment (CTF) of beta APP under control of the cytomegalovirus enhancer/chicken beta-actin promoter. The transgenic mRNA was detected in many tissues of these mice, but the levels of transgenic mRNA, CTF, and A beta did not correlate well indicating that tissue-specific posttranslational processing may play an important role in determining the amount of A beta that accumulates in various tissues. A beta was detected biochemically in brain, kidney, and pancreas with the largest amount present in pancreas. In transgenic plasma, there was a marked accumulation of human A beta 1-40 and A beta 1-42(43) to levels over 30-times those observed in normal human plasma. Thus, the transgenic mice produce and secrete considerable A beta. Despite this increase in A beta secretion and the elevated A beta in brain, immunohistochemistry revealed no consistent cerebral A beta deposition. In pancreas, however, intracellular A beta deposits were detected immunohistochemically in acinar cells and interstitial macrophages, some of which showed severe degeneration. In addition, examination of these cells by immunoelectron microscopy revealed many putative amyloid fibrils (7-12 nm) that were stained by anti-A beta antibodies. Overall, our findings indicate that tissue-specific posttranslational processing may play a pivotal role in A beta production and amyloid fibril formation in vivo. By carefully analyzing the changes that occur in the transgenic mice described here as compared to the transgenic line that has recently been shown to form extracellular amyloid plaques in brain, it may be possible to gain considerable insight into the factors that determine the location and amount of A beta that accumulates as amyloid.
- Published
- 1996
- Full Text
- View/download PDF
22. Displaced ganglion cells in the chick retina.
- Author
-
Prada FA, Chmielewski CE, Dorado ME, Prada C, and Génis-Gálvez JM
- Subjects
- Animals, Cell Count, Silver, Staining and Labeling, Chickens anatomy & histology, Retina cytology, Retinal Ganglion Cells cytology
- Abstract
New morphological and cytological data on the displaced ganglion cells (DGCs) in the chick retina are presented. Analysis of the topographic distribution, cellular number, dendritic field, perikaryon size and ultrastructural characteristics are included. The DGCs were found predominantly in the peripheral retina. The sizes of the DGCs, 18-42 microns, observed either by Normarsky's interferential contrast or by silver impregnation techniques, spanned the size range of the other retinal neurons. The results support the hypothesis that DGCs, in the chick retina, may constitute a specific morphofunctional system, and therefore they might not be considered as neurons that fail to attain the normal location of ganglion cells during the developmental process of migration.
- Published
- 1989
- Full Text
- View/download PDF
23. Effect of light deprivation upon the morphology of axon terminals in the dorsal lateral geniculate nucleus of mouse: an electron microscopical study using serial sections.
- Author
-
Prada C
- Subjects
- Animals, Axons physiology, Geniculate Bodies physiology, Mice, Mice, Inbred C57BL, Microscopy, Electron, Neurons classification, Neurons ultrastructure, Synaptic Vesicles ultrastructure, Time Factors, Axons ultrastructure, Darkness, Geniculate Bodies ultrastructure, Sensory Deprivation
- Abstract
Two populations of morphologically different large axon terminals have been observed electron microscopically in the dorsal lateral geniculate nucleus of mice raised in complete darkness from birth up to 19 days of age. One population includes larger terminals indistinguishable from the large terminals present in control animals, i.e. they have round synaptic vesicles, rather pale mitochondria, membrane saculae, coated vesicles, and asymmetric contacts with encrusted dendritic spines of portions of dendrites of geniculo-cortical relay neurons. The other population includes large terminals which also have asymmetric contacts with encrusted dendritic spines or portions of dendrites of geniculo-cortical relay neurons, but they show darker mitochondria, absence of both membrane saculae and coated vesicles, and significantly higher synaptic vesicle density and smaller size than the large control ones. We suggest that the latter population of terminals could be inactive due to the absence of visual input.
- Published
- 1987
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.