Cellulosic fibres reinforced composite blend films of starch/poly(vinyl alcohol) (PVA) were prepared by using citric acid as plasticizer and glutaraldehyde as the cross-linker. The mechanical ...properties of cellulosic fibres reinforced composite blend were compared with starch/PVA crossed linked blend films. The increase in the tensile strength, elongation percentage, degree of swelling and biodegradability of blend films was evaluated as compared to starch/PVA crosslinked blend films. The value of different evaluated parameters such as citric acid, glutaraldehyde and reinforced fibre to starch/PVA (5:5) was found to be 25 wt.%, 0.100 wt.% and 20 wt.%, respectively. The blend films were characterized using Fourier transform-infrared spectrophotometry (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA/DTA/DTG). Scanning electron microscopy illustrated a good adhesion between starch/PVA blend and fibres. The blend films were also explored for antimicrobial activities against pathogenic bacteria like Staphylococcus aureus and Escherichia coli. The results confirmed that the blended films may be used as exceptional material for food packaging.
An experience of anxiety is caused by the anticipation of unseen future events, especially in the context of ecological trauma, where the prospect of a world without humans in the distant future is ...often portrayed through mediated cinematic memories. As a result of anthropological intervention on our planet, it is feared that humanity will cease to exist unless steps are taken to prevent it. Furthermore, as climate change intensifies, humans are left with more questions regarding their future. One recent film that addresses this issue is Christopher Nolan’s Tenet (2020). The film explores the concept of a dying Earth in the future, whose inhabitants seek help from the past to restore the planet’s balance by reversing entropy. Despite failing to provide any remedy by revealing ‘What’s happened happened’, a viewpoint that Christopher Nolan, as an auteur, has already presented in his previous film Interstellar (2014), the film leaves the audience with the question, what is the purpose of projecting an unseen trauma? By evaluating the events that contributed to the image of a crumbling Earth in the film, this paper seeks to examine the concept of future trauma as an indication of post-traumatic stress disorder while simultaneously exploring it as a film that acknowledges Nolan’s own anxiety over the decline of a medium he cherishes.
Pluripotent stem cells have long-term proliferative capacity and an unusual mode of cell-cycle regulation and can divide independently of extrinsic mitogenic signals. The last few years has seen ...evidence emerge that links cell-cycle regulation to the maintenance and establishment of pluripotency. Myc transcription factors appear to be central to this regulation. This review addresses these links and discusses how cell-cycle controls and Myc impact on the maintenance and establishment of pluripotency.
The sugar industry has shaped the development of Fiji's economy for over a century; but, for the past 15 years, sugarcane production has been declining. A study was undertaken of over 300 sugarcane ...farmers in Fiji to determine the benefits of crop diversification and to compare the level of profitability for farmers fully dedicated to sugarcane farming and sugarcane farmers who have diversified. The findings demonstrate that a farmer in the latter group was able to achieve 45% higher profitability than one in the former. Fiji has the potential to increase farm output from diversification, but the relevant stakeholders need to help farmers secure markets and provide appropriate guidance and training.
A general mechanism for how intracellular signaling pathways in human pluripotent cells are coordinated and how they maintain self-renewal remain to be elucidated. In this report, we describe a ...signaling mechanism where PI3K/Akt activity maintains self-renewal by restraining prodifferentiation signaling through suppression of the Raf/Mek/Erk and canonical Wnt signaling pathways. When active, PI3K/Akt establishes conditions where Activin A/Smad2,3 performs a pro-self-renewal function by activating target genes, including Nanog. When PI3K/Akt signaling is low, Wnt effectors are activated and function in conjunction with Smad2,3 to promote differentiation. The switch in Smad2,3 activity after inactivation of PI3K/Akt requires the activation of canonical Wnt signaling by Erk, which targets Gsk3β. In sum, we define a signaling framework that converges on Smad2,3 and determines its ability to regulate the balance between alternative cell states. This signaling paradigm has far-reaching implications for cell fate decisions during early embryonic development.
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► Akt promotes pluripotency by modulating Activin/Smad2,3 activity and repressing Erk ► Erk and Wnt cooperate to inhibit Gsk3β and promote differentiation ► β-catenin and Smad2,3 cooperate to induce mesendoderm differentiation ► At low doses, Gsk3 inhibitors promote self-renewal by increasing Myc stability
Claudins are cell-cell adhesion proteins, which are expressed in tight junctions (TJs), the most common apical cell-cell adhesion. Claudin proteins help to regulate defense and barrier functions, as ...well as differentiation and polarity in epithelial and endothelial cells. A series of studies have now reported dysregulation of claudin proteins in cancers. However, the precise mechanisms are still not well understood. Nonetheless, studies have clearly demonstrated a causal role of multiple claudins in the regulation of epithelial to mesenchymal transition (EMT), a key feature in the acquisition of a cancer stem cell phenotype in cancer cells. In addition, claudin proteins are known to modulate therapy resistance in cancer cells, a feature associated with cancer stem cells. In this review, we have focused primarily on highlighting the causal link between claudins, cancer stem cells, and therapy resistance. We have also contemplated the significance of claudins as novel targets in improving the efficacy of cancer therapy. Overall, this review provides a much-needed understanding of the emerging role of claudin proteins in cancer malignancy and therapeutic management.
Obesity increases susceptibility to multiple organ disorders, however, underlying mechanisms remain unclear. The subclinical inflammation assisted by obesity-induced gut permeability may underlie ...obesity-associated co-morbidities. Despite eminent clinical significance of the obesity led gut barrier abnormalities, its precise molecular regulation remains unclear. It is also unknown whether barrier deregulations, similar to the gut, characterize other vital organs in obese individuals. The claudin family of proteins is integral to the tight junction (TJ), the apical cell-cell adhesion and a key regulator of the epithelial barrier. Using comprehensive physiological and biochemical analysis of intestinal and renal tissues from high-fat diet fed mice, critical for maintaining metabolic homeostasis, this study demonstrates that profound TJ-restructuring by organ and tissue-specific claudin switching characterize obese organs. Protein expression and cellular distribution were examined. In-silico analysis further highlighted potential association of select claudins, modulated by the obesity, with signaling and metabolic pathways of pathological significance. In vitro studies using Leptin or DCA-treatment suggested causal significance of obesity-induced changes in tissue microenvironment in regulating barrier deregulations in tissue-specific manner. Overall, current findings advances our understanding of the molecular undertakings of obesity associated changes that help predispose to specific diseases and also identifies novel windows of preventive and/or therapeutic interventions.
The role of the tight junctions (TJ) in controlling paracellular traffic of ions and molecules, through the regulation of claudin proteins, is now established. However, it has also become ...increasingly evident that claudin proteins, as integral components of the TJs, play crucial role in maintaining the cell–cell integrity. In conformity, deregulation of claudin expression and cellular distribution in cancer tissues has been widely documented and correlated with cancer progression and metastasis. However, this correlation is not unidirectional and rather suggests tissue specific regulations. Irrespective, if the widely described correlations between altered claudin expression and cancer initiation/progression could be established, they may serve as important markers for prognostic purposes and potential therapeutic targets. In this review, we summarize data from screening of the cancer tissues, manipulation of claudin expression in cells and animals subjected to cancer models, and how claudins are regulated in cancer. The focus of this article remains analysis of the association between cancer and the claudins and to decipher clinical relevance.
We study the opening of double stranded DNA (dsDNA) in the presence of molecular crowders using the Peyrard-Bishop-Dauxois (PBD) model. It is a known fact that about 15-20% of the total volume of a ...cell is occupied by molecular crowders. The presence of crowders in the model is represented through the potential depth in the Morse potential. Using equilibrium statistical calculations we find the melting profile and the melting probabilities of the chain. We found that the melting temperature,
T
m
, increases in the presence of a crowder. This is due to the fact that the crowders occupy a substantial amount of the system volume and hence reduce the free volume available to the DNA molecule. This restricts the free movement of base pairs and hence the DNA molecule, which results in an increase in the melting temperature of the DNA molecule. We also find a correlation between the melting temperature and the crowder density of the solution. The power law behaviour shows that the melting temperature scales linearly with the crowder density. At a given density, a higher density of crowder may suppress the free movement in the DNA molecule, which will increase
T
m
. Although the temperature changes occurring
in vitro
seem to be smaller than those observed in this work, the results demonstrate interesting features of the opening of DNA molecules in crowded environments.
We study the opening of double stranded DNA (dsDNA) in the presence of molecular crowders using the Peyrard-Bishop-Dauxois (PBD) model.
Despite significant improvements in clinical management, pancreatic cancer (PC) remains one of the deadliest cancer types, as it is prone to late detection with extreme metastatic properties. The ...recent findings that pancreatic cancer stem cells (PaCSCs) contribute to the tumorigenesis, progression, and chemoresistance have offered significant insight into the cancer malignancy and development of precise therapies. However, the heterogeneity of cancer and signaling pathways that regulate PC have posed limitations in the effective targeting of the PaCSCs. In this regard, the role for K-RAS, TP53, Transforming Growth Factor-β, hedgehog, Wnt and Notch and other signaling pathways in PC progression is well documented. In this review, we discuss the role of PaCSCs, the underlying molecular and signaling pathways that help promote pancreatic cancer development and metastasis with a specific focus on the regulation of PaCSCs. We also discuss the therapeutic approaches that target different PaCSCs, intricate mechanisms, and therapeutic opportunities to eliminate heterogeneous PaCSCs populations in pancreatic cancer.
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