Publications by authors named "Gunawardena A"

Article Synopsis
  • - The study explored the effects of palovarotene, a RARγ agonist, on existing osteochondromas using a mouse model, showing that higher doses effectively stopped tumor growth compared to a control group.
  • - Both systemic administration and nanoparticle-based local delivery of palovarotene kept the size of tumors stable, with significant reductions in tumor growth observed.
  • - Transcriptome and pathway analyses indicated that palovarotene activates the osteoarthritis pathway and specifically stimulates the Stat3 pathway in chondrocytes, suggesting a mechanism for its effectiveness against osteochondromas.
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Programmed cell death (PCD) is fundamentally important for plant development, abiotic stress responses and immunity, but our understanding of its regulation remains fragmented. Building a stronger research community is required to accelerate progress in this area through knowledge exchange and constructive debate. In this Viewpoint, we aim to initiate a collective effort to integrate data across a diverse set of experimental models to facilitate characterisation of the fundamental mechanisms underlying plant PCD and ultimately aid the development of a new plant cell death classification system in the future.

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Aponogeton madagascariensis, commonly known as the lace plant, produces leaves that form perforations by programmed cell death (PCD). Leaf development is divided into several stages beginning with "pre-perforation" furled leaves enriched with red pigmentation from anthocyanins. The leaf blade is characterized by a series of grids known as areoles bounded by veins.

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While the imminent extinction of many species is predicted, prevention is expensive, and decision-makers often have to prioritise funding. In democracies, it can be argued that conservation using public funds should be influenced by the values placed on threatened species by the public, and that community views should also affect the conservation management approaches adopted. We conducted on online survey with 2400 respondents from the general Australian public to determine 1) the relative values placed on a diverse set of 12 threatened Australian animal species and 2) whether those values changed with the approach proposed to conserve them.

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Background: The lace plant (Aponogeton madagascariensis) is an aquatic monocot that develops leaves with uniquely formed perforations through the use of a developmentally regulated process called programmed cell death (PCD). The process of perforation formation in lace plant leaves is subdivided into several developmental stages: pre-perforation, window, perforation formation, perforation expansion and mature. The first three emerging "imperforate leaves" do not form perforations, while all subsequent leaves form perforations via developmentally regulated PCD.

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Premise: Lace plant (Aponogeton madagascariensis) leaves are remodeled via developmental programmed cell death (PCD) to produce perforations located equidistantly between longitudinal and transverse veins. Auxin has been implicated in other developmental PCD processes in plants; however, the role of auxin in perforation formation in lace plant is unknown. Here the role of auxin in developmental PCD in lace plant was studied using two auxin inhibitors N-1-naphthylphthalamic acid (NPA), an auxin transport inhibitor, and auxinole, a potent auxin antagonist.

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Programmed cell death (PCD) is the destruction of unwanted cells through an intracellularly mediated process. Perforation formation in the lace plant (Aponogeton madagascariensis) provides an excellent model for studying developmentally regulated PCD. Ca fluxes have previously been identified as important signals for PCD in plants and mammals.

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The lace plant () is an aquatic monocot that utilizes programmed cell death (PCD) to form perforations throughout its mature leaves as part of normal development. The lace plant is an emerging model system representing a unique form of developmental PCD. The role of autophagy in lace plant PCD was investigated using live cell imaging, transmission electron microscopy (TEM), immunolocalization, and pharmacological experimentation.

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Lace plant leaves utilize programmed cell death (PCD) to form perforations during development. The role of heat shock proteins (Hsps) in PCD during lace plant leaf development is currently unknown. Hsp70 amounts were measured throughout lace plant leaf development, and the results indicate that it is highest before and during PCD.

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Active cell proliferation and turnover in the growth plate is essential for embryonic and postnatal bone growth. We performed a lineage tracing of Wnt/β-catenin signaling responsive cells (Wnt-responsive cells) using Axin2 ;Rosa26ZsGreen mice and found a novel cell population that resides in the outermost layer of the growth plate facing the Ranvier's groove (RG; the perichondrium adjacent to growth plate). These Wnt-responsive cells rapidly expanded and contributed to formation of the outer growth plate from the neonatal to the growing stage but stopped expanding at the young adult stage when bone longitudinal growth ceases.

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Industrialization and urbanization, as a result of rapid economic development, have led to the deterioration of water quality in many rivers in developing countries. The Kelani River in Sri Lanka provides drinking water to Colombo and a range of market and non-market ecosystem services; but these services are threatened by deteriorating water quality. We apply a hydro-economic model that accounts for spatial patterns of water quality and abatement cost variability between firms in the catchment.

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Water quality of the Kelani River has become a critical issue in Sri Lanka due to the high cost of maintaining drinking water standards and the market and non-market costs of deteriorating river ecosystem services. By integrating a catchment model with a river model of water quality, we developed a method to estimate the effect of pollution sources on ambient water quality. Using integrated model simulations, we estimate (1) the relative contribution from point (industrial and domestic) and non-point sources (river catchment) to river water quality and (2) pollutant transfer coefficients for zones along the lower section of the river.

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Due to the involvement of macroautophagy/autophagy in different pathophysiological conditions such as infections, neurodegeneration and cancer, identification of novel small molecules that modulate the process is of current research and clinical interest. In this work, we developed a luciferase-based sensitive and robust kinetic high-throughput screen (HTS) of small molecules that modulate autophagic degradation of peroxisomes in the budding yeast Saccharomyces cerevisiae. Being a pathway-specific rather than a target-driven assay, we identified small molecule modulators that acted at key steps of autophagic flux.

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Antioxidants and reactive oxygen species are integral for programmed cell death signaling during perforation formation in the lace plant ( Aponogeton madagascariensis ). The lace plant is an excellent model system for studying developmentally regulated programmed cell death (PCD). During early lace plant leaf development, PCD systematically deletes cells resulting in a perforated leaf morphology that is unique in planta.

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Hundreds of ERP studies have reported a midfrontal negative-going amplitude shift following negative compared with positive action outcomes. This feedback-related negativity (FRN) effect is typically thought to reflect an early and binary mechanism of action evaluation in the posterior midcingulate cortex. However, in prior research on the FRN effect, the instantaneous value and the long-term value of action outcomes have been perfectly confounded.

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Osteoarthritis (OA) is one of most common skeletal disorders and can affect synovial joints such as knee and ankle joints. α5 integrin, a major fibronectin receptor, is expressed in articular cartilage and has been demonstrated to play roles in synovial joint development and in the regulation of chondrocyte survival and matrix degradation in articular cartilage. We hypothesized that α5 integrin signaling is involved in pathogenesis of OA.

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Article Synopsis
  • Programmed cell death (PCD) plays a vital role in plant growth, defense against pathogens, and adaptability to environmental challenges.
  • This chapter offers specific methods to effectively investigate PCD linked to plant development and stress responses.
  • Techniques like the root hair assay and electrolyte leakage assay allow for measuring PCD and cellular damage due to abiotic stress, while the lace plant serves as a model for examining genetic control of PCD in leaf development.
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Cartilage not only plays essential roles in skeletal development and growth during pre- and postnatal stages but also serves to provide smooth movement of skeletons throughout life. Thus, dysfunction of cartilage causes a variety of skeletal disorders. Results from animal studies reveal that β-catenin-dependent canonical and independent non-canonical Wnt signaling pathways have multiple roles in regulation of cartilage development, growth, and maintenance.

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The lace plant, Aponogeton madagascariensis, is an aquatic monocot that forms perforations in its leaves as part of normal leaf development. Perforation formation occurs through developmentally regulated programmed cell death (PCD). The molecular basis of PCD regulation in the lace plant is unknown, however ethylene has been shown to play a significant role.

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Background: Programmed cell death (PCD) is an important process for the development and maintenance of multicellular eukaryotes. In animals, there are three morphologically distinct cell death types: apoptosis, autophagic cell death, and necrosis. The search for an all-encompassing classification system based on plant cell death morphology continues.

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Hereditary Multiple Exostoses (HME) is an autosomal-dominant disorder characterized by benign cartilage tumors (exostoses) forming near the growth plates, leading to severe health problems. EXT1 and EXT2 are the two genes known to harbor heterozygous loss-of-function mutations that account for the vast majority of the primary genetic component of HME. However, patients present with wide clinical heterogeneity, suggesting that modifier genes play a role in determining severity.

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Article Synopsis
  • Aponogeton madagascariensis uses programmed cell death (PCD) to create leaf perforations, starting between veins and expanding outwards.
  • Researchers explored the role of mitochondria, caspases, and the actin cytoskeleton in this process, using various inhibitors and stains.
  • The study found that the activity of caspase-1 increases early in perforation development, and that inhibiting this activity, along with mitochondrial function, prevents PCD and actin breakdown, indicating that mitochondria may trigger caspase activity in this process.
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