Salicylic acid (SA), a ubiquitous phenolic phytohormone, is involved in many plant physiological processes including stomatal movement. We analysed SA-induced stomatal closure, production of reactive ...oxygen species (ROS) and nitric oxide (NO), cytosolic calcium ion (Ca²⁺cyt) oscillations and inward-rectifying potassium (K⁺ in) channel activity in Arabidopsis. SA-induced stomatal closure was inhibited by pre-treatment with catalase (CAT) and superoxide dismutase (SOD), suggesting the involvement of extracellular ROS. A peroxidase inhibitor, SHAM (salicylhydroxamic acid) completely abolished SA-induced stomatal closure whereas neither an inhibitor of NADPH oxidase (DPI) nor atrbohD atrbohF mutation impairs SA-induced stomatal closures. 3,3′-Diaminobenzidine (DAB) and nitroblue tetrazolium (NBT) stainings demonstrated that SA induced H₂O₂ and O₂ ⁻ production. Guard cell ROS accumulation was significantly increased by SA, but that ROS was suppressed by exogenous CAT, SOD and SHAM. NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) suppressed the SA-induced stomatal closure but did not suppress guard cell ROS accumulation whereas SHAM suppressed SA-induced NO production. SA failed to induce Ca²⁺cyt oscillations in guard cells whereas K⁺ in channel activity was suppressed by SA. These results indicate that SA induces stomatal closure accompanied with extracellular ROS production mediated by SHAM-sensitive peroxidase, intracellular ROS accumulation and K⁺ in channel inactivation.
The blue phase liquid crystal (BPLC) is a highly ordered liquid crystal (LC) phase found very close to the LC-isotropic transition. The BPLC has demonstrated potential in next-generation display and ...photonic technology due to its exceptional properties such as sub-millisecond response time and wide viewing angle. However, BPLC is stable in a very small temperature range (0.5-1 °C) and its driving voltage is very high (∼100 V). To overcome these challenges recent research has focused on solutions which incorporate polymers or nanoparticles into the blue phase to widen the temperature range from around few °C to potentially more than 60 °C. In order to reduce the driving voltage, strategies have been attempted by modifying the device structure by introducing protrusion or corrugated electrodes and vertical field switching mechanism has been proposed. In this paper the effectiveness of the proposed solution will be discussed, in order to assess the potential of BPLC in display technology and beyond.
Mobile edge computing (MEC) is being introduced and leveraged in many domains, but few studies have addressed MEC for secure in-home therapy management. To this end, this paper presents an in-home ...therapy management framework, which leverages the IoT nodes and the blockchain-based decentralized MEC paradigm to support low-latency, secure, anonymous, and always-available spatiotemporal multimedia therapeutic data communication within an on-demand data-sharing scenario. To the best of our knowledge, this non-invasive, MEC-based IoT therapy platform is first done by our group. This platform can provide a full-body joint range of motion data for physically challenged individuals in a decentralized manner. With MEC, the framework can provide therapy diagnostic and analytical data on demand to a large portion of humanity who are either born with disabilities or became disabled due to accidents, war-time injuries, or old age. For security, the framework uses blockchain-Tor-based distributed transactions to preserve the therapeutic data privacy, ownership, generation, storage, and sharing. Our initial test results from a complete implementation of the framework show that it can support a sufficiently large number of users without considerable increase in mean processing time.
Bioactive plant derived compounds are important for a wide range of therapeutic applications, and some display promising anticancer properties. Further evidence suggests that phytochemicals modulate ...autophagy and apoptosis, the two crucial cellular pathways involved in the underlying pathobiology of cancer development and regulation. Pharmacological targeting of autophagy and apoptosis signaling using phytochemicals therefore offers a promising strategy that is complementary to conventional cancer chemotherapy. In this review, we sought to highlight the molecular basis of the autophagic-apoptotic pathway to understand its implication in the pathobiology of cancer, and explore this fundamental cellular process as a druggable anticancer target. We also aimed to present recent advances and address the limitations faced in the therapeutic development of phytochemical-based anticancer drugs.
The demand for natural food colorants is growing as consumers question the use of artificial colorants more and more. The phycobiliprotein C-phycocyanin of
Arthospira platensis
is used as a natural ...blue colorant in certain food products. The thermoacidophilic red microalga
Cyanidioschyzon merolae
might provide an alternative source of phycocyanin.
Cyanidioschyzon merolae
belongs to the order Cyanidiophyceae of the phylum Rhodophyta. Its natural habitat are sulfuric hot springs and geysers found near volcanic areas in, e.g., Yellowstone National Park in the USA and in Java, Indonesia. It grows optimally at a pH between 0.5 and 3.0 and at temperatures up to 56 °C. The low pH at which
C
.
merolae
grows minimizes the risk of microbial contamination and could limit production loss. As
C
.
merolae
lacks a cell wall, phycocyanin with a high purity number of 9.9 could be extracted by an osmotic shock using a simple ultrapure water extraction followed by centrifugation. The denaturation midpoint at pH 5 was 83 °C, being considerably higher than the
A
.
platensis
phycocyanin (65 °C). The
C
.
merolae
phycocyanin was relatively stable at pH 4 and 5 up to 80 °C. The high thermostability at slightly acidic pH makes the
C
.
merolae
phycocyanin an interesting alternative to
A
.
platensis
phycocyanin as a natural blue food colorant.
Recently, a large number of mathematical models that are described by delay differential equations (DDEs) have appeared in the life sciences. In this paper, we present a delay differential model to ...describe the interactions between the effector and tumour cells. The existence of the possible steady states and their local stability and change of stability via Hopf bifurcation are theoretically and numerically investigated. Parameter estimation problem for given real observations, using least squares approach, is studied. The global stability and sensitivity analysis are also numerically proved for the model. The stability and periodicity of the solutions may depend on the time-lag parameter. The model is qualitatively consistent with the experimental observations of immune-induced tumour dormancy. The model also predicts dormancy as a transient period of growth which necessarily results in either tumour elimination or tumour escape.
Background: Dentists have a vital role in detection of the signs and symptoms of obstructive sleep apnea (OSA) as it modifies in anatomy of orofacial structures. Aims and Objectives: This study aims ...to assess the prevalence of OSA risk in patients attending dental department and explore the factors related with high-risk OSA. Materials and Methods: The study was carried in the Al-Farabi Dental College, Jeddah, Saudi Arabia, on 200 consecutive dental patients from June 1, 2018, to July 31, 2019. Demographic details and the OSA risk were evaluated based on the Berlin questionnaire (Arabic version). Two qualified investigators independently did anthropometric measurements, medical and dental examination. Results: About 3.7% of males and 13.8% of females were found to be at high risk of OSA. Obese individuals almost had twice more likely chance to have OSA symptoms. Conclusion: Our findings confirm that dentists have an important role in recognizing the OSA signs and symptoms.
Surface‐enhanced Raman spectroscopy (SERS) is now widely used as a rapid and inexpensive tool for chemical/biochemical analysis. The method can give enormous increases in the intensities of the Raman ...signals of low‐concentration molecular targets if they are adsorbed on suitable enhancing substrates, which are typically composed of nanostructured Ag or Au. However, the features of SERS that allow it to be used as a chemical sensor also mean that it can be used as a powerful probe of the surface chemistry of any nanostructured material that can provide SERS enhancement. This is important because it is the surface chemistry that controls how these materials interact with their local environment and, in real applications, this interaction can be more important than more commonly measured properties such as morphology or plasmonic absorption. Here, the opportunity that this approach to SERS provides is illustrated with examples where the surface chemistry is both characterized and controlled in order to create functional nanomaterials.
Surface‐enhanced Raman spectroscopy (SERS) is a powerful technique for probing the chemical structure of adsorbed surface layers on nanostructured materials. Currently, it is predominantly used for detecting the adsorption of small molecules, but it also provides information on the surface chemistry of enhancing materials themselves. This is important since it is the surface chemistry that governs the interaction of the materials with their environment.
Scrub typhus is an acute febrile illness caused by the intracellular pathogen Orientia tsutsugamushi. The clinical features include fever, myalgia, lymphadenopathy, and dry mouth. However, no studies ...have assessed the symptom of dry mouth in patients with scrub typhus. We investigated the pattern of salivary scintigraphy during the acute febrile state and compared it with any changes after treatment. Fourteen patients underwent both pre- and post-treatment salivary scintigraphy. Imaging analysis was conducted using radioactivity in the oral cavity, parotid glands, and submandibular glands. During the acute phase, the radioactivity in the oral cavity markedly decreased, while that in the parotid and submandibular glands was preserved. After treatment, radioactivity in the oral cavity showed a significant increase at 20-min, 40-min, and after wash-out. The ejection fraction (%) of the parotid glands also increased after treatment. In contrast, the radioactivity levels of the parotid and submandibular glands were not statistically different after treatment. Salivary scintigraphy indicated that insufficient saliva excretion from the salivary glands into the oral cavity was one reason for the dry mouth reported by patients with scrub typhus. In the future, salivary scintigraphy imaging could contribute to the evaluation of dry mouth in patients with scrub typhus.
Autophagy is a vacuolar, lysosomal degradation pathway for injured and damaged protein molecules and organelles in eukaryotic cells, which is controlled by nutrients and stress responses. ...Dysregulation of cellular autophagy may lead to various diseases such as neurodegenerative disease, obesity, cardiovascular disease, diabetes, and malignancies. Recently, natural compounds have come to attention for being able to modulate the autophagy pathway in cancer prevention, although the prospective role of autophagy in cancer treatment is very complex and not yet clearly elucidated. Numerous synthetic chemicals have been identified that modulate autophagy and are favorable candidates for cancer treatment, but they have adverse side effects. Therefore, different phytochemicals, which include natural compounds and their derivatives, have attracted significant attention for use as autophagy modulators in cancer treatment with minimal side effects. In the current review, we discuss the promising role of natural compounds in modulating the autophagy pathway to control and prevent cancer, and provide possible therapeutic options.
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