Sugar alcohols-induced oxidative metabolism in cotton callus culture

Sugar alcohols (mannitol and sorbitol) may cause oxidative damage in plants if used in higher concentration. Our present experiment was undertaken to study physiological and metabolic responses in cotton (Gossypium hirsutum L.) callus against mannitol and sorbitol higher doses. Both markedly declined mean values of relative fresh weight growth rates with the increase in their concentration intensities. The overall protein and malonaldehyde (MDA) contents increased in the stressed-shocked cells. Also, the mean values of various antioxidants such as superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX) and calalase (CAT) quantitatively improved over their respective controls. As a whole, MDA contents were higher in magnitude than that of different antioxidant enzymes. Also values of relative increase in case of POD were higher as compared to SOD showing the ability of cotton callus culture to scavenge H2O2 produced as a result of the activity of SOD. Our results show that both agents caused greater damage to the membranous structure in comparison to less activation of the antioxidants. As a whole, the overall change regarding fresh weight growth rates was less after 14-day stress regime, while the mean values of the antioxidant enzymes activities were lower after the 28-day stress period. Such decrease conveys the message that less reactive oxygen species (ROS) might have been produced.Keywords: Antioxidants, callus culture, Gossypium hirsutum L., osmotic stress, sugar alcoholsAfrican Journal of Biotechnology Vol. 12(17), pp. 2191-220

Utilising virtual reality in pain management : a systematic review

Virtual reality (VR) offers patient with a drug free supplement, an alternative or complementary therapy to traditional pain management. VR technology allowing its use in a wide variety of settings in the medicine world. So, we would like to evaluate the current existing evidence supporting VR in pain management. We conducted a systematic review of interventional and observational studies that examined VR applications in pain management between 2010 and 2019. We used Scopus databases, PubMed, Web of Science, Ovid MEDLINE and EBSCOhost to identify the studies using keywords “patient”, “virtual reality”, “medicine” and “pain management”. Data was obtained by two investigators and agreement was reached with the involvement of a third and fourth investigator. Narrative synthesis for all research was done. A total of 451 citations were identified, among which 12 studies met the criteria for inclusion. Studies involve various countries with participant age ranging from 6 to 75 years old. Studies were small, employed different design, instrument and measure for outcome. Studies addressed experimental, acute and chronic pain with four categories of condition which are burn injury, orthopedic diseases and chronic headache. VR was effective during the procedure in experimental and acute pain management. Majority of studies involving VR in painful physical rehabilitation therapy found VR reduced chronic pain and some provide evidence of lasting analgesia effect of VR after therapy. The usage of VR in chronic pain in term of psychological and cognitive behavioral therapy (CBT) showed improvement of positive mood, emotional and motivation that could lead to improvement of quality of life. VR also useful to elicit findings during painful cervical kinematics assessment in chronic neck pain. VR is a promising technology to be applied in managing chronic and acute pain. Some research showed that VR usage is able to provide lasting effect of analgesia even after VR session. However, there is a need for long term, larger sample sizes and well controlled studies to show clinical and cost-effectiveness for this technology to be used in clinical settings

Effects of Neem (Azadirachta indica) seed and Turmeric (Curcuma longa) rhizome extracts on aphids control, plant growth and yield in okra

The use of synthetic pesticides to control pests and increase crops yield is a common practice, but they cause several environmental and health problems. Therefore, there is a need to explore alternative approaches to reduce the sole dependence on synthetic pesticides. The present study was conducted to screen the extracts of Neem seed and Turmeric rhizome for pesticidal activities against okra pests (aphids). Experiments were conducted in field with four plots. One plot was kept as a control (unsprayed) and one was sprayed with synthetic pesticides, one with Neem seeds extract and one with Turmeric rhizome extract. The effect on number of pests, plant growth and yield was observed at regular intervals. A significant reduction in pests was recorded in all treatments as compared to the control. Neem seed extract was more effective than Turmeric rhizome extract as revealed by a 73% decrease in aphids by Neem extract in comparison to 54% by Turmeric extract after last application. Both the extracts were found to be more effective than the synthetic pesticides in controlling okra pests. Both the extracts had stimulatory effects on okra growth and yield. For example, the total yield of plots sprayed with Neem (53.3 kg plot-1) and Turmeric extract (47.7 kg plot-1) was higher than the yield of control plot (33.8 kg plot-1) and plot sprayed with synthetic pesticides (39 kg plot-1). It is concluded that Neem and Turmeric extracts can be used as alternative of synthetic pesticides for controlling pests attacks in okra

Elastic properties of TeO2-B2O3-Ag2O glasses.

A series of glasses [(TeO2) x (B2O3)1−x ]1−y [Ag2O] y with x = 70 and y = 10, 15, 20, 25 and 30 mol% were synthesised by rapid quenching. Longitudinal and shear ultrasonic velocity were measured at room temperature and at 5 MHz frequency. Elastic properties, Poisson's ratio, microhardness, softening temperature and Debye temperature have been calculated from the measured density and ultrasonic velocity at room temperature. The experimental results indicate that the elastic constants depend upon the composition of the glasses and the role of the Ag2O inside the glass network is discussed. Estimated parameters based on Makishima–Mackenzie theory and bond compression model were calculated in order to analyse the experimental elastic moduli. Comparison between the experimental elastic moduli data obtained in the study and the calculated theoretically by the mentioned above models has been discussed

The Advancement of Biomaterials in Regulating Stem Cell Fate.

Stem cells are well-known to have prominent roles in tissue engineering applications. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) can differentiate into every cell type in the body while adult stem cells such as mesenchymal stem cells (MSCs) can be isolated from various sources. Nevertheless, an utmost limitation in harnessing stem cells for tissue engineering is the supply of cells. The advances in biomaterial technology allows the establishment of ex vivo expansion systems to overcome this bottleneck. The progress of various scaffold fabrication could direct stem cell fate decisions including cell proliferation and differentiation into specific lineages in vitro. Stem cell biology and biomaterial technology promote synergistic effect on stem cell-based regenerative therapies. Therefore, understanding the interaction of stem cell and biomaterials would allow the designation of new biomaterials for future clinical therapeutic applications for tissue regeneration. This review focuses mainly on the advances of natural and synthetic biomaterials in regulating stem cell fate decisions. We have also briefly discussed how biological and biophysical properties of biomaterials including wettability, chemical functionality, biodegradability and stiffness play their roles

Targeted agents and immunotherapies: optimizing outcomes in melanoma

Treatment options for patients with metastatic melanoma, and especially BRAF-mutant melanoma, have changed dramatically in the past 5 years, with the FDA approval of eight new therapeutic agents. During this period, the treatment paradigm for BRAF-mutant disease has evolved rapidly: the standard-of-care BRAF-targeted approach has shifted from single-agent BRAF inhibition to combination therapy with a BRAF and a MEK inhibitor. Concurrently, immunotherapy has transitioned from cytokine-based treatment to antibody-mediated blockade of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and, now, the programmed cell-death protein 1 (PD-1) immune checkpoints. These changes in the treatment landscape have dramatically improved patient outcomes, with the median overall survival of patients with advanced-stage melanoma increasing from approximately 9 months before 2011 to at least 2 years - and probably longer for those with BRAF-V600-mutant disease. Herein, we review the clinical trial data that established the standard-of-care treatment approaches for advanced-stage melanoma. Mechanisms of resistance and biomarkers of response to BRAF-targeted treatments and immunotherapies are discussed, and the contrasting clinical benefits and limitations of these therapies are explored. We summarize the state of the field and outline a rational approach to frontline-treatment selection for each individual patient with BRAF-mutant melanoma

Catalyst characteristics and performance of silica-supported zinc for hydrodeoxygenation of phenol

The present investigation aimed to study the physicochemical characteristics of supported catalysts comprising various percentages of zinc dispersed over SiO2. The physiochemical properties of these catalysts were surveyed by N2physisorption (BET), thermogravimetry analysis (TGA), H2temperature-programmed reduction, field-emission scanning electron microscopy (FESEM), inductively coupled plasma-optical emission spectrometry (ICP-OES), and NH3temperature-programmed desorption (NH3-TPD). In addition, to examine the activity and performance of the catalysts for the hydrodeoxygenation (HDO) of the bio-oil oxygenated compounds, the experimental reaction runs, as well as stability and durability tests, were performed using 3% Zn/SiO2as the catalyst. Characterization of silica-supported zinc catalysts revealed an even dispersion of the active site over the support in the various dopings of the zinc. The acidity of the calcinated catalysts elevated clearly up to 0.481 mmol/g. Moreover, characteristic outcomes indicate that elevating the doping of zinc metal led to interaction and substitution of proton sites on the SiO2surface that finally resulted in an increase in the desorption temperature peak. The experiments were performed at temperature 500 °C, pressure 1 atm; weight hourly space velocity (WHSV) 0.32 (h-1); feed flow rate 0.5 (mL/min); and hydrogen flow rate 150 (mL/min). Based on the results, it was revealed that among all the prepared catalysts, that with 3% of zinc had the highest conversion efficiency up to 80%. However, the selectivity of the major products, analyzed by gas chromatography flame-ionization detection (GC-FID), was not influenced by the variation in the active site doping