262,525 research outputs found
"Avaliação da expressão de genes associados ao sistema imune durante os estágios de desenvolvimento do camarão Litopenaeus vannamei"
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e do Desenvolvimento, Florianópolis, 2013.Os cultivos de camarão, tanto nas fazendas quanto nas larviculturas, são susceptíveis à ocorrência de mortalidades causadas por micro-organismos patogênicos, tais como vírus, bactérias e fungos. A grande maioria dos estudos sobre os mecanismos de defesa dos camarões enfocam principalmente a problemática ocorrida nos viveiros de cultivo com animais juvenis e adultos. Por outro lado, tais estudos são ainda escassos nas fases larvais e pós-larvais, mas são igualmente importantes, uma vez que enfermidades nesses estágios podem gerar perdas econômicas consideráveis para as larviculturas. Assim, o presente estudo teve como objetivo ampliar o conhecimento sobre a ontogenia do sistema imune durante o desenvolvimento de Litopenaeus vannamei, a espécie de camarão mais cultivada no mundo, através da avaliação da expressão de genes associados ao seu sistema imune utilizando RT-qPCR. Foram analisados 17 genes, de diferentes categorias funcionais, em subestágios de desenvolvimento: ovos fertilizados (0-4h e 7-11h pós-desova), Náuplios (I e V), Protozoeas (I e III), Misis (I e III) e Pós-larvas (2, 9 e 17). Todos os genes avaliados mostraram-se expressos no estágio de Pós-larva, o qual é o mais próximo de camarões juvenis. Os genes associados à defesa antiviral (Lv-Sid 1, LvDcr2 e Lv-Ago 2, LvDcr1, LvSVC1 e Lv-Ago 1), reconhecimento de micro-organismos (LvDscam), antioxidante (Lv-PRX), sinalização intracelular (fatores de transcrição LvDorsal e LvRelish) e apoptose (LvIAP) foram ubiquamente expressos de ovo a pós-larvas. Enquanto a expressão de genes envolvidos no sistema pró-fenoloxidase (LvproPO-1), a homeostasia (LvHHAP), coagulação (LvClot) e peptídeos antimicrobianos (Litvan PEN2, Litvan PEN3 e LvSty-II) não foi detectada em todos os subestágios. De maneira interessante, a expressão de genes de uma mesma família gênica (Litvan PEN2 e Litvan PEN3) não ocorreu simultaneamente em um mesmo subestágio de desenvolvimento. Por outro lado, os genes associados à defesa antiviral (LvDcr1/2, Lv-Ago 1/2 and Lv-Sid-1), fatores de transcrição (LvDorsal e xii LvRelish), defesa antioxidante (Lv-PRX) e apoptose (LvIAP) foram mais expressos no Ovo 0-4h em comparação ao Ovo 7-11h, sugerindo uma contribuição materna. A expressão de genes associados ao sistema imune nas fases larvais e pós-larvais de L. vannamei ressalta a importância de se conhecer o estabelecimento dos diferentes mecanismos de defesa ao longo do seu desenvolvimento. Assim, o presente estudo vem contribuir, de maneira original e pioneira, com informações a respeito da ontogenia de moléculas do sistema imune, especialmente àquelas associadas à defesa antiviral. Conhecimentos desta natureza poderão contribuir, em um futuro próximo, para o desenvolvimento de ferramentas biotecnológicas que servirão para avaliar as condições de saúde de animais nos cultivos (larviculturas e fazendas), bem como para orientar à seleção genética de camarões mais resistentes à infecções microbianas e virais.Abstract : Shrimp farms and hatcheries are susceptible to mortalities events caused by pathogenic microorganisms, such as virus, bacteria and fungi. The great majority of studies related to the defense mechanisms of shrimp are focused in problems that occur mainly in juvenile and adult shrimp farming. Moreover, studies in the shrimp larval and post-larval stages are very limited but are equally important, since diseases can generate considerable economic losses in those stages. Thus, the present study was aimed to expand the knowledge on the ontogeny of the immune system during the development of Litopenaeus vannamei, the most cultivated shrimp species in the world, through the evaluation of gene expression associated with the immune system using RT-qPCR. The stages examined in this work included the fertilized egg (0h and 7h post spawns), nauplius (I and V), protozoea (I and III), Mysis (I and III) and postlarval (PL2, PL9 and PL17). As result, it was observed that all analyzed genes were expressed in the post-larval stage, which is the previous stage to juvenile shrimp. While genes associated to antiviral defense (LvDcr1, LvDcr2, Lv-Ago 1, Lv-Ago 2, Lv-Sid-1 and LvSVC-1), microorganisms recognition(LvDscam), antioxidant defense (Lv-PRX), intracellular signaling (transcription factors LvDorsal and LvRelish) and apoptosis (LvIAP) were constitutively expressed from egg to postlarvae; genes involved in the prophenoloxidase system (LvproPO-1), homeostasis (LvHHAP), coagulation (LvClot) and antimicrobial peptides (Litvan PEN2, Litvan PEN3 and LvSty-II) were not detected in all stages. Interestingly, the expression of the same gene family (Litvan PEN2 and Litvan PEN3) did not occur simultaneously during the development. In addition, genes associated with antiviral defense (LvDcr1, LvDcr2, Lv-Ago 1, Lv-Ago 2 and Lv-Sid 1), transcription factors (LvDorsal and LvRelish), antioxidant defense (Lv-PRX) and apoptosis (LvIAP) were more expressed in egg 0h compared to egg 7h, which suggests a maternal contribution. The expression of genes associated with the immune system in larval and postlarval stages of L. vannamei highlights the importance of understanding the establishment of different defense mechanisms throughout the organism development. Thus, the present study aims to contribute in an original and pioneering way, with information about the ontogeny of molecules of the immune system, with especial attention given to molecules associated with antiviral defense. Such knowledge can contribute in the near future for the development of biotechnological tools to evaluate the health of animals in culture (hatchery and farm), as well as the genetic selection of shrimps more resistant to microbial and viral infections
A disposable electrochemical biosensor for l-DOPA determination in undiluted human serum
No full textA disposable electrochemical biosensor for the determination of L-DOPA in undiluted human serum is described.
It is based on the use of a carbon nanotubes-modified screen printed electrode covered with an electropolymerized poly(thionine) film and an outer cross-linked layer containing tyrosinase. Further coverage of the sensor with a Nafion layer allows its use directly in human serum, obviating the need for sample pretreatment.
The sensor exhibited a linear behavior in the 0.8–22 μM concentration range and offers promise for decentralized clinical testing of L-DOPA
Penaeid shrimp ALFs cluster into four groups.
No full text<p>ALF sequences from penaeid shrimps and horseshoe crabs, and scygonadins from crabs (outgroup) were aligned with MAFFT alignment program prior to phylogenetic analysis. The tree was constructed using the Neighbour-Joining method (Pairwise deletion) in MEGA 4. Bootstrap sampling was reiterated 1,000 times. Sequences included in analyses were the following: (i) <u>Shrimp ALFs</u>: black tiger shrimp <i>Penaeus monodon</i> (<i>Penmon</i> ALF-A1 or ALF<i>Pm</i>2: ABP73291; <i>Penmon</i> ALF-A1 or ALF<i>Pm</i>1: ABP73290; <i>Penmon</i> ALF-B1 or ALF<i>Pm</i>3: ABP73289; <i>Penmon</i> ALF-B2 and -B3 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067937#pone.0067937-Somboonwiwat3" target="_blank">[47]</a>; <i>Penmon</i> ALF-B4: ADC32520; <i>Penmon</i> ALF-C1 or ALF<i>Pm</i>6: ADM21460; <i>Penmon</i> ALF-C2 or ALF<i>Pm</i>6: AER45468), kuruma prawn (<i>Marjap</i> ALF-A1 or <i>Mj</i>ALF2: BAH22585; <i>Marjap</i> ALF-C1 or M-ALF: BAE92940), fleshy prawn <i>Fenneropenaeus chinensis</i> (<i>Fenchi</i> ALF-B1 or ALF<i>Fc</i>: AAX63831), Indian prawn <i>F. indicus</i> (<i>Fenind</i> ALF-B1: ADE27980; <i>Fenind</i> ALF-B2: ADK94454), pink shrimp <i>Farfantepenaeus paulensis</i> (<i>Farpau</i> ALF-B1 or ALF<i>Fpau</i>: ABQ96193), Atlantic white shrimp <i>Litopenaeus setiferus</i> (<i>Litset</i> ALF-D1: BE846661), Pacific white leg shrimp <i>L. vannamei</i> (<i>Litvan</i> ALF-A1 or <i>Lv</i>ALF1: EW713395; <i>Litvan</i> ALF-A2: FE087264; <i>Litvan</i> ALF-B1 or ALF<i>Lv</i>3: ABB22833; <i>Litvan</i> ALF-B2 or ALF<i>Lv</i>2: ABB22832; <i>Litvan</i> ALF-C1: FE153599; <i>Litvan</i> ALF-C2: FE176556; <i>Litvan</i> ALF-C3: FE058235; <i>Litvan</i> ALF-C4: FE079082; <i>Litvan</i> ALF-C5: FE088301; <i>Litvan</i> ALF-C6: FE078559; <i>Litvan</i> ALF-C7: FE079755; <i>Litvan</i> ALF-C8: FE105941; <i>Litvan</i> ALF-C9: FE090668; <i>Litvan</i> ALF-C10: FE052210; <i>Litvan</i> ALF-C11: FE088625; <i>Litvan</i> ALF-C12 or: <i>Lv</i>ALF2: EW713396; <i>Litvan</i> ALF-D1: FE152534; <i>Litvan</i> ALF-D2: FE151634; <i>Litvan</i> ALF-D3: FE110967; <i>Litvan</i> ALF-D4: FE115964), Southern white shrimp <i>L. schmitti</i> (<i>Litsch</i> ALF-B1 or ALF<i>Lsch</i>: ABJ90465) and blue shrimp <i>L. stylirostris</i> (<i>Litsty</i> ALF-B1: AGH32549; <i>Litsty</i> ALF-D1: AAY33769); (ii) <u>Horseshoe crab ALFs</u>: Chinese horseshoe crab <i>Tachypleus tridentatus</i> (TACTR_ALF: P07087; TACTR2_ALF: AAK00651), Atlantic horseshoe crab <i>Limulus polyphemus</i> (LIMPO_ALF: P07086) and Southeast Asian horseshoe crab <i>Carcinoscorpius rotundicauda</i> (CARRO_ALF: CK086627); (iii) <u>Scygonadins (outgroup):</u> giant mud crab <i>Scylla serrata</i> (<i>S serrata</i> scygonadin: AAW57403; <i>S serrata</i> scygonadin-2: ABI96918; <i>S serrata</i> SSAP: ABM05493) and green crab <i>Carcinus maenas</i> (<i>C. maenas</i> scygonadin: DY307310).</p
Inutile de nommer étoiles, constellations, galaxies: <i>El entenado</i> de Juan José Saer
No full textInternational audienc
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Supplementary Table 1 from A Comparative and Integrative Approach Identifies <i>ATPase Family, AAA Domain Containing 2</i> as a Likely Driver of Cell Proliferation in Lung Adenocarcinoma
No full textPDF file, 44K, LitVAn significant terms for gene clusters f and i in the unsupervised analysis of gene expression.</p
Elevated Levels of Methylmalonate and Homocysteine in Parkinson's Disease, Progressive Supranuclear Palsy and Amyotrophic Lateral Sclerosis
No full textBackground/Aims: Increasing evidence suggests that elevated levels of homocysteine (Hcy) and methylmalonate (MMA) may be involved in the pathogenesis of neurodegenerative diseases. Methods: The urine levels of MMA and serum levels of Hcy as well as folic acid and vitamin B 12 were measured in patients suffering from the distinct neurodegenerative diseases progressive supranuclear palsy (PSP), amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD), and compared to age-and gender-matched control subjects. Results: We found significantly elevated concentrations of Hcy (PD 15.1, PSP 15.8, ALS 13.9, control 11.2 mu mol/l) and MMA (PD 3.7, PSP 3.1, ALS 3.7, control 1.8 mg/g) in all patient groups in comparison with controls. Levels of Hcy and MMA did not differ significantly between the neurodegenerative diseases. Conclusion: Our findings might imply that Hcy and MMA are released as a consequence of neurodegeneration regardless of the underlying cause and serve as surrogate markers of neurodegeneration. Alternatively they might be directly implicated in the pathogenesis of these diseases. Since elevated levels of both Hcy and MMA are neurotoxic, further studies might investigate the effect of vitamin therapy on disease progression. Copyright (C) 2010 S. Karger AG, Base
Proton Magnetic Resonance Spectroscopic Imaging in progressive supranuclear palsy, Parkinson’s disease, and corticobasal degeneration
No full textProtecting Animals 36: Author Witi Ihimaera
No full textIn this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship
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