Crescimento inicial da cana-de-açúcar em função do tamanho do mini-rebolo e da aplicação de bioestimulantes

The correct use of amino acids and humic substances can increase plant growth and development. Thus, this study aimed to test the interaction effect of an amino acid and a humic substance with the size of sugar cane mini cutting sover the early sugar cane development. The experiment was conducted at the Sugar cane Experimental Station in Paranavaí City. The cultivar used was the RB867515 and the evaluation was performed at 60 days after planting. One used a completely randomized design in a factorial arrangement with three blocks (3x5x3). Beyond the control treatment, the biostimulants used were a humic substance and the L-glutamic acid. The five types of sugar cane mini cutting shad the following sizes: 0 (just the bud), 2, 4, 8, 12 and 16 cm. It can be concluded that, under the conditions of the experiment realization and evaluation, there was no interaction between the reserves of the mini cutting sand the application of the humic substances and the amino acid used. The root surface area, root diameter, root volume, root dry mass and dry mass of shoots showed a linear behavior, crescent and significant, according to the size of the mini cuttings. Os aminoácidos e as substâncias húmicas, deste que corretamente usados, podem auxiliar no crescimento e no desenvolvimento das culturas. Assim, este estudo teve por objetivo testar a interação do efeito de um aminoácido e de uma substância húmica com o tamanho do mini-rebolo no desenvolvimento inicial da cana-de-açúcar. O experimento foi conduzido na Estação Experimental de Cana-de-açúcar de Paranavaí-UFPR. A cultivar utilizada foi a RB867515 e as avaliações foram efetuadas aos 60 dias após o plantio. Foi utilizado o delineamento inteiramente casualizado em arranjo fatorial com três repetições (3x5x3). Os tamanhos dos mini-rebolos testados foram cinco, a saber: 0 (somente a gema), 2, 4, 8, 12 e 16 cm. Além da testemunha, os bioestimulantes aplicados foram uma substância húmica e o ácido L-glutâmico.  Pode-se concluir que, nas condições de realização e avaliação do experimento, não há interação entre o comprimento da reserva do tolete e a aplicação dos bioestimulantes testados. A área superficial radicular, o diâmetro radicular, o volume radicular, a massa seca radicular e a massa seca da parte aérea tiveram um comportamento linear, crescente e significativo, em função do comprimento do tolete.Los aminoácidos y sustancias húmicas utilizados correctamente, pueden ayudar en el crecimiento y desarrollo de los cultivos. Este estudio tuvo como objetivo poner a prueba la interacción de los efectos de un aminoácido y una sustancia húmica con el tamaño del "mini-rebolo" (tolete) en el desarrollo inicial de la caña de azúcar. El experimento se llevó a cabo en la Estación Experimental de caña de azúcar de Paranavaí-UFPR. El cultivo utilizado fue RB867515 y las evaluaciones fueron realizadas 60 días después del plantío. Se utilizó un diseño completamente al azar en un arreglo factorial con tres repeticiones (3x5x3). Los tamaños de los toletes testados fueron cinco, como sigue: 0 (sólo la yema), 2, 4, 8, 12 y 16 cm. Además del control, los bioestimulantes aplicados fueron una sustancia húmico y acido L-glutámico. Se puede concluir que en las condiciones de aplicación y evaluación del experimento no hay interacción entre la longitud de la reserva del tolete y la aplicación de los bioestimulantes evaluados. El área de superficie, diámetro, volumen, peso seco de las raíces y masa seca de la parte aérea tuvieron un comportamiento lineal, creciente y significativo, debido a la longitud del tolete

Mast cell repopulation of the peritoneal cavity: contribution of mast cell progenitors versus bone marrow derived committed mast cell precursors

<p>Abstract</p> <p>Background</p> <p>Mast cells have recently gained new importance as immunoregulatory cells that are involved in numerous pathological processes. One result of these processes is an increase in mast cell numbers at peripheral sites. This study was undertaken to determine the mast cell response in the peritoneal cavity and bone marrow during repopulation of the peritoneal cavity in rats.</p> <p>Results</p> <p>Two mast cell specific antibodies, mAb AA4 and mAb BGD6, were used to distinguish the committed mast cell precursor from more mature mast cells. The peritoneal cavity was depleted of mast cells using distilled water. Twelve hours after distilled water injection, very immature mast cells could be isolated from the blood and by 48 hours were present in the peritoneal cavity. At this same time the percentage of mast cells in mitosis increased fourfold. Mast cell depletion of the peritoneal cavity also reduced the total number of mast cells in the bone marrow, but increased the number of mast cell committed precursors.</p> <p>Conclusions</p> <p>In response to mast cell depletion of the peritoneal cavity, a mast cell progenitor is released into the circulation and participates in repopulation of the peritoneal cavity, while the committed mast cell precursor is retained in the bone marrow.</p

Identificação de precursores de mastócitos na medula óssea e no sangue periférico de roedores

Orientadora: Prof.ª Dr.ª Maria Célia JamurDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Curso de Pós-Graduação em MorfologiaInclui referências: p. 48-55Área de concentração: Biologia CelularResumo: Estudos sobre a maturação de mastócitos têm sido dificultados pela falta de marcadores específicos para mastócitos e os mastócitos imaturos não podem ser identificados apenas pelas suas características morfológicas. Os mastócitos imaturos não apresentam grânulos citoplasmáticos típicos de mastócitos e possuem características morfológicas semelhantes a outros tipos celulares. No presente estudo, mastócitos derivados da medula óssea de ratos e camundongos foram identificados e caracterizados por métodos imunoquímicos. A análise por citometria de fluxo e a contagem direta de células isoladas imunomagneticamente ou imunomarcadas, mostram que os mastócitos representam aproximadamente 2,4% da população total de células da medula óssea. Com a conjugação a esferas magnéticas de anticorpos monoclonais (mAbs) específicos para mastócitos, mAb BGD6 e mAb AA4, foi possível isolar uma população pura de mastócitos da medula óssea. Mastócitos em três distintos estágios de maturação foram identificados: maduro, imaturo e bem imaturo. Estas células têm o seu tamanho variando entre 3 e 13 um e são imunomarcadas positivamente pelo mAb AA4 e pelo mAb BGD6. Elas também são positivas para o receptor de alta afinidade para IgE, IgE e c-kit. Utilizando isolamento sequencial com o mAb AA4 seguido pelo mAb BGD6, um precursor comprometido com a linhagem de mastócitos também pode ser identificado. Estes precursores comprometidos perfazem 0,02% das células da medula óssea, são células indiferenciadas e apresentam os antígenos de superfície c-kit e CD 34. Mastócitos não são encontrados no sangue circulante, porém seus precursores devem migrar da medula óssea para os tecidos periféricos, através da circulação. Foi utilizado o modelo da depleção de mastócitos peritoneais, através da lise pela injeção intraperitoneal de água destilada, para estimular a migração de precursores durante o repovoamento da cavidade peritoneal. Utilizando este modelo, pela primeira vez, uma pequena população de precursores de mastócitos foram isolados do sangue circulante, < 1/ 10^6 células. Morfologicamente e fenotipicamente, estes mastócitos circulantes assemelham-se aos mastócitos bem imaturos encontrados na medula óssea. Os resultados apresentados indicam a presença, na medula óssea, de uma população de mastócitos em todos os estágios de maturação, desde o precursor comprometido até o mastócito maduro. No entanto, este estudo demonstra que pelo menos os mastócitos bem imaturos podem circular pelo sangue durante o repovoamento de sítios periféricos.Summary: Studies of mast cell maturation have been hampered because there have been no specific markers for mast cells and the immature mast cells are not easily identified based solely on morphological characteristics. Immature mast cells lack the cytoplasmic granules typical of mature mast cells as well as sharing morphological features with other cell types. In the present study, rat and mouse bone marrow derived mast were identified and characterized using immunochemical methods. By flow cytometry, and by direct counting of immunostained or immunomagnetically isolated cells, the mast cells represent approximately 2.4% of the total cell population in bone marrow. By conjugating the mast cells specific monoclonal antibodies (mAbs), mAb AA4 and mAb BGD6, to magnetic beads, it was possible to isolate a pure population of mast cells from bone marrow. Three distinct stages of maturation were identified, mature, immature and very immature. These cells ranged in size from 13 pm - 3 pm and immunostained positively with mAb AA4 and mAb BGD6. They were also positive for the high affinity IgE receptor, IgE and c-kit. In addition, using sequential isolation first with mAb AA4 and then mAb BGD6, a committed mast cell precursor also could be identified. This cell makes up only 0.02% of the cells in the bone marrow, has a very undifferentiated morphology, and consistent with being a mast cell precursor, is c-kit and CD34 positive. Although mast cells are thought to migrate from the bone marrow to peripheral sites in the tissue through the circulation, mast cells have not been seen in circulating blood. Lysis of peritoneal mast cells by distilled water was used in order to stimulate the migration of mast cells from the bone marrow into the peripheral circulation during repopulation of the peritoneal cavity. Using this model system, for the first time very small numbers of mast cells, <1/10^6 cells, could be isolated from circulating blood. Morphologically and phenotypically, these circulating mast cells resembled the very immature mast cells present in bone marrow. The results of this investigation demonstrate that mast cells are present in the bone marrow in all stages of maturation ranging from committed precursor to mature mast cell. Furthermore, this study indicates that at least the very immature mast cells can circulate through the blood during repopulation of peripheral sites

Mis-Trafficking of Endosomal Urokinase Proteins Triggers Drug-Induced Glioma Nonapoptotic Cell Death

5-Benzylglycinyl-amiloride (UCD38B) is the parent molecule of a class of anticancer small molecules that kill proliferative and nonproliferative high-grade glioma cells by programmed necrosis. UCD38B intracellularly triggers endocytosis, causing 40-50% of endosomes containing proteins of the urokinase plasminogen activator system (uPAS) to relocate to perinuclear mitochondrial regions. Endosomal "mis-trafficking" caused by UCD38B in human glioma cells corresponds to mitochondrial depolarization with the release and nuclear translocation of apoptotis-inducing factor (AIF) followed by irreversible caspase-independent cell demise. High-content quantification of immunocytochemical colocalization studies identified that UCD38B treatment increased endocytosis of the urokinase plasminogen activator (uPA), its receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1) into the early and late endosomes by 4- to 5-fold prior to AIF nuclear translocation and subsequent glioma demise. PAI-1 was found to comparably relocate with a subset of early and late endosomes in four different human glioma cell lines after UCD38B treatment, followed by caspase-independent, nonapoptotic cell death. Following UCD38B treatment, the receptor guidance protein LRP-1, which is required for endosomal recycling of the uPA receptor to the plasmalemma, remained abnormally associated with PAI-1 in early and late endosomes. The resultant aberrant endosomal recycling increased the total cellular content of the uPA-PAI-1 protein complex. Reversible inhibition of cellular endocytosis demonstrated that UCD38B bypasses the plasmalemmal uPAS complex and directly acts intracellularly to alter uPAS endocytotic trafficking. UCD38B represents a class of small molecules whose anticancer cytotoxicity is a consequence of causing the mis-trafficking of early and late endosomes containing uPAS cargo and leading to AIF-mediated necrotic cell death

Oxygen tension modulates differentiation and primary macrophage functions in the human monocytic THP-1 cell line.

The human THP-1 cell line is widely used as an in vitro model system for studying macrophage differentiation and function. Conventional culture conditions for these cells consist of ambient oxygen pressure (∼20% v/v) and medium supplemented with the thiol 2-mercaptoethanol (2-ME) and serum. In consideration of the redox activities of O₂ and 2-ME, and the extensive experimental evidence supporting a role for reactive oxygen species (ROS) in the differentiation and function of macrophages, we addressed the question of whether culturing THP-1 cells under a more physiologically relevant oxygen tension (5% O₂) in the absence of 2-ME and serum would alter THP-1 cell physiology. Comparisons of cultures maintained in 18% O₂versus 5% O₂ indicated that reducing oxygen tension had no effect on the proliferation of undifferentiated THP-1 cells. However, decreasing the oxygen tension to 5% O₂ significantly increased the rate of phorbol ester-induced differentiation of THP-1 cells into macrophage-like cells as well as the metabolic activity of both undifferentiated and PMA-differentiated THP-1 cells. Removal of both 2-ME and serum from the medium decreased the proliferation of undifferentiated THP-1 cells but increased metabolic activity and the rate of differentiation under either oxygen tension. In differentiated THP-1 cells, lowering the oxygen tension to 5% O₂ decreased phagocytic activity, the constitutive release of β-hexosaminidase and LPS-induced NF-κB activation but enhanced LPS-stimulated release of cytokines. Collectively, these data demonstrate that oxygen tension influences THP-1 cell differentiation and primary macrophage functions, and suggest that culturing these cells under tightly regulated oxygen tension in the absence of exogenous reducing agent and serum is likely to provide a physiologically relevant baseline from which to study the role of the local redox environment in regulating THP-1 cell physiology

Oxygen tension modulates differentiation and primary macrophage functions in the human monocytic THP-1 cell line.

The human THP-1 cell line is widely used as an in vitro model system for studying macrophage differentiation and function. Conventional culture conditions for these cells consist of ambient oxygen pressure (∼20% v/v) and medium supplemented with the thiol 2-mercaptoethanol (2-ME) and serum. In consideration of the redox activities of O₂ and 2-ME, and the extensive experimental evidence supporting a role for reactive oxygen species (ROS) in the differentiation and function of macrophages, we addressed the question of whether culturing THP-1 cells under a more physiologically relevant oxygen tension (5% O₂) in the absence of 2-ME and serum would alter THP-1 cell physiology. Comparisons of cultures maintained in 18% O₂versus 5% O₂ indicated that reducing oxygen tension had no effect on the proliferation of undifferentiated THP-1 cells. However, decreasing the oxygen tension to 5% O₂ significantly increased the rate of phorbol ester-induced differentiation of THP-1 cells into macrophage-like cells as well as the metabolic activity of both undifferentiated and PMA-differentiated THP-1 cells. Removal of both 2-ME and serum from the medium decreased the proliferation of undifferentiated THP-1 cells but increased metabolic activity and the rate of differentiation under either oxygen tension. In differentiated THP-1 cells, lowering the oxygen tension to 5% O₂ decreased phagocytic activity, the constitutive release of β-hexosaminidase and LPS-induced NF-κB activation but enhanced LPS-stimulated release of cytokines. Collectively, these data demonstrate that oxygen tension influences THP-1 cell differentiation and primary macrophage functions, and suggest that culturing these cells under tightly regulated oxygen tension in the absence of exogenous reducing agent and serum is likely to provide a physiologically relevant baseline from which to study the role of the local redox environment in regulating THP-1 cell physiology

The Organophosphorus Pesticide Chlorpyrifos Induces Sex-Specific Airway Hyperreactivity in Adult Rats.

Occupational and environmental exposures to organophosphorus pesticides (OPs) are associated with increased incidence of asthma and other pulmonary diseases. Although the canonical mechanism of OP neurotoxicity is inhibition of acetylcholinesterase (AChE), it was previously reported that the OP chlorpyrifos (CPF) causes airway hyperreactivity (AHR) in guinea pigs at levels that do not inhibit lung or brain AChE. The guinea pig is considered to have inherently hyperresponsive airways, thus, cross-species validation is needed to confirm relevance to humans. Additionally, sex differences in asthma incidence have been demonstrated in the human population, but whether OP-induced AHR is sex-dependent has not been systematically studied in a preclinical model. In this study, 8-week old male and female Sprague Dawley rats were administered CPF at doses causing comparable AChE inhibition in whole lung homogenate (30 mg/kg in males, 7 mg/kg in females, sc) prior to assessing pulmonary mechanics in response to electrical stimulation of the vagus nerves at 24 h, 48 h, 72 h, 7 d or 14 d post-exposure in males, and 24 h or 7 d post-exposure in females. CPF significantly potentiated vagally induced airway resistance and tissue elastance at 7 d post-exposure in males, and at 24 h and 7 d post-exposure in females. These effects occurred independent of significant AChE inhibition in cerebellum, blood, trachealis, or isolated airway, suggesting that AChE independent OP-induced airway hyperreactivity is a cross-species phenomenon. These findings have significant implications for assessing the risk posed by CPF, and potentially other OPs, to human health and safety