144 research outputs found
Antibacterial activity of the released metabolites of sea anemone Stichodactyla gigantea (Forskal, 1775) from the coast of South Andaman, India
Marine sessile organisms produce unique bioactive metabolites, which render a defensive barrier against microbial threats and increase survivability in the middle of predators. The earlier studies focused on isolated metabolites from marine sources, composed to exhibit antibacterial, antiviral, and cytotoxic properties. The present study aims to evaluate the antibacterial property of the anemone-released metabolites. The crude and released mucoid metabolite obtained from the sea anemone Stichodactyla gigantea (Forskal, 1775) assayed against five human pathogens like Bacillus subtilis (MTCC 121), Listeria monocytogenes (MTCC 839), Staphylococcus aureus (MTCC839), Bacillus cereus (MTCC 443), and Salmonella enterica typhimurium (MTCC 1252). The assay exhibited positive activity against two pathogens, viz. B. subtilis (MTCC 121) and L. monocytogenes (MTCC 839). Based on the demonstrated activity, the released metabolites were purified using Open Column chromatography. The fractions collected were subjected to an antibacterial assay, which showed a high inhibition zone of 39 mm and 23 mm in diameter against B. subtilis and L. monocytogenes. Followingly, the characterization of purified fractions through GC-MS analysis confirmed the presence of 22 compounds. This study reveals the potential power of the released mucoid metabolites against antibiotic-resistive pathogens. Further studies are essential to elucidate the role of endosymbiont's contribution to mucoid production and their responsiveness towards tackling stressed conditions
Antibacterial activity of the released metabolites of sea anemone Stichodactyla gigantea (Forskal, 1775) from the coast of South Andaman, India
Marine sessile organisms produce unique bioactive metabolites, which render a defensive barrier against microbial threats and increase survivability in the middle of predators. The earlier studies focused on isolated metabolites from marine sources, composed to exhibit antibacterial, antiviral, and cytotoxic properties. The present study aims to evaluate the antibacterial property of the anemone-released metabolites. The crude and released mucoid metabolite obtained from the sea anemone Stichodactyla gigantea (Forskal, 1775) assayed against five human pathogens like Bacillus subtilis (MTCC 121), Listeria monocytogenes (MTCC 839), Staphylococcus aureus (MTCC839), Bacillus cereus (MTCC 443), and Salmonella enterica typhimurium (MTCC 1252). The assay exhibited positive activity against two pathogens, viz. B. subtilis (MTCC 121) and L. monocytogenes (MTCC 839). Based on the demonstrated activity, the released metabolites were purified using Open Column chromatography. The fractions collected were subjected to an antibacterial assay, which showed a high inhibition zone of 39 mm and 23 mm in diameter against B. subtilis and L. monocytogenes. Followingly, the characterization of purified fractions through GC-MS analysis confirmed the presence of 22 compounds. This study reveals the potential power of the released mucoid metabolites against antibiotic-resistive pathogens. Further studies are essential to elucidate the role of endosymbiont's contribution to mucoid production and their responsiveness towards tackling stressed conditions
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Genes Contributing to Staphylococcus aureus Fitness in Abscess- and Infection-Related Ecologies
ABSTRACT Staphylococcus aureus is a leading cause of both community- and hospital-acquired infections that are increasingly antibiotic resistant. The emergence of S. aureus resistance to even last-line antibiotics heightens the need for the development of new drugs with novel targets. We generated a highly saturated transposon insertion mutant library in the genome of S. aureus and used Tn-seq analysis to probe the entire genome, with unprecedented resolution and sensitivity, for genes of importance in infection. We further identified genes contributing to fitness in various infected compartments (blood and ocular fluids) and compared them to genes required for growth in rich medium. This resulted in the identification of 426 genes that were important for S. aureus fitness during growth in infection models, including 71 genes that could be considered essential for survival specifically during infection. These findings highlight novel as well as previously known genes encoding virulence traits and metabolic pathways important for S. aureus proliferation at sites of infection, which may represent new therapeutic targets
Turmeric and Its Major Compound Curcumin on Health: Bioactive Effects and Safety Profiles for Food, Pharmaceutical, Biotechnological and Medicinal Applications
Curcumin, a yellow polyphenolic pigment from the Curcuma longa L. (turmeric) rhizome, has been used for centuries for culinary and food coloring purposes, and as an ingredient for various medicinal preparations, widely used in Ayurveda and Chinese medicine. In recent decades, their biological activities have been extensively studied. Thus, this review aims to offer an in-depth discussion of curcumin applications for food and biotechnological industries, and on health promotion and disease prevention, with particular emphasis on its antioxidant, anti-inflammatory, neuroprotective, anticancer, hepatoprotective, and cardioprotective effects. Bioavailability, bioefficacy and safety features, side effects, and quality parameters of curcumin are also addressed. Finally, curcumin’s multidimensional applications, food attractiveness optimization, agro-industrial procedures to offset its instability and low bioavailability, health concerns, and upcoming strategies for clinical application are also covered
Singing for lung health in COPD: a multicentre randomised controlled trial of online delivery
BACKGROUND: Singing for lung health (SLH) is an arts-based breathing control and movement intervention for people with long-term respiratory conditions, intended to improve symptoms and quality of life. Online, remotely delivered programmes might improve accessibility; however, no previous studies have assessed the effectiveness of this approach. METHODS: We conducted an assessor-blind randomised controlled trial comparing the impact of 12 weeks of once-weekly online SLH sessions against usual care on health-related quality of life, assessed using the RAND 36-Item Short Form Health Survey (SF-36) Mental Health Composite (MHC) and Physical Health Composite (PHC) scores. RESULTS: We enrolled 115 people with stable chronic obstructive pulmonary disease (COPD), median (IQR) age 69 (62-74), 56.5% females, 80% prior pulmonary rehabilitation, Medical Research Council dyspnoea scale 4 (3-4), forced expiratory volume in 1 s % predicted 49 (35-63). 50 participants in each arm completed the study. The intervention arm experienced improvements in physical but not mental health components of RAND SF-36; PHC (regression coefficient (95% CI): 1.77 (95% CI 0.11 to 3.44); p=0.037), but not MHC (0.86 (95% CI -1.68 to 3.40); p=0.504). A prespecified responder analysis based on achieving a 10% improvement from baseline demonstrated a response rate for PHC of 32% in the SLH arm and 12.7% for usual care (p=0.024). A between-group difference in responder rate was not found in relation to the MHC (19.3% vs 25.9%; p=0.403). DISCUSSION AND CONCLUSION: A 12-week online SLH programme can improve the physical component of quality of life for people with COPD, but the overall effect is relatively modest compared with the impact seen in research using face-to-face group sessions. Further work on the content, duration and dose of online interventions may be useful. TRIAL REGISTRATION NUMBER: NCT04034212
HIV Delays IFN-α Production from Human Plasmacytoid Dendritic Cells and Is Associated with SYK Phosphorylation
Plasmacytoid dendritic cells (pDC) are the major producers of type I interferons (IFNs) in humans and rapidly produce IFN-α in response to virus exposure. Although HIV infection is associated with pDC activation, it is unclear why the innate immune response is unable to effectively control viral replication. We systematically compared the effect of HIV, Influenza, Sendai, and HSV-2 at similar target cell multiplicity of infection (M.O.I.) on human pDC function. We found that Influenza, Sendai, HSV-2 and imiquimod are able to rapidly induce IFN-α production within 4 hours to maximal levels, whereas HIV had a delayed induction that was maximal only after 24 hours. In addition, maximal IFN-α induction by HIV was at least 10 fold less than that of the other viruses in the panel. HIV also induced less TNF-α and MIP-1β but similar levels of IP-10 compared to other viruses, which was also mirrored by delayed upregulation of pDC activation markers CD83 and CD86. BDCA-2 has been identified as an inhibitory receptor on pDC, signaling through a pathway that involves SYK phosphorylation. We find that compared to Influenza, HIV induces the activation of the SYK pathway. Thus, HIV delays pDC IFN-α production and pDC activation via SYK phosphorylation, allowing establishment of viral populations
Estimation of the number of synapses in the hippocampus and brain-wide by volume electron microscopy and genetic labeling
Determining the number of synapses that are present in different brain regions is crucial to understand brain connectivity as a whole. Membrane-associated guanylate kinases (MAGUKs) are a family of scaffolding proteins that are expressed in excitatory glutamatergic synapses. We used genetic labeling of two of these proteins (PSD95 and SAP102), and Spinning Disc confocal Microscopy (SDM), to estimate the number of fluorescent puncta in the CA1 area of the hippocampus. We also used FIB-SEM, a three-dimensional electron microscopy technique, to calculate the actual numbers of synapses in the same area. We then estimated the ratio between the three-dimensional densities obtained with FIB-SEM (synapses/µm) and the bi-dimensional densities obtained with SDM (puncta/100 µm). Given that it is impractical to use FIB-SEM brain-wide, we used previously available SDM data from other brain regions and we applied this ratio as a conversion factor to estimate the minimum density of synapses in those regions. We found the highest densities of synapses in the isocortex, olfactory areas, hippocampal formation and cortical subplate. Low densities were found in the pallidum, hypothalamus, brainstem and cerebellum. Finally, the striatum and thalamus showed a wide range of synapse densities.This work was supported by grants from the following entities: the Spanish “Ministerio de Ciencia, Innovación y Universidades” (Grant PGC2018-094307-B-I00 and the Cajal Blue Brain Project [C080020-09; the Spanish partner of the Blue Brain Project initiative from EPFL, Switzerland]; the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No. 785907 (Human Brain Project, SGA2); the Wellcome Trust (Technology Development Grant 202932); and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (695568 SYNNOVATE). L.T.-R. is a recipient of grants from the EMBO Long-term fellowship 2016–2018 and the IBRO-PERC InEurope grants programme
Pediatric multiple sclerosis: update on diagnostic criteria, imaging, histopathology and treatment choices
Pediatric multiple sclerosis (MS) represents less than 5% of the MS population, but patients with pediatric-onset disease reach permanent disability at a younger age than adult onset patients. Accurate diagnosis at presentation and optimal long-term treatment is vital to mitigate ongoing neuroinflammation and irreversible neurodegeneration.
However, it may be difficult to early differentiate pediatric MS from acute disseminated
encephalomyelitis (ADEM) and neuromyelitis optica spectrum disorders (NMOSD) as they often have atypical presentation that differs from that of adult-onset MS. The
purpose of this review is to summarize the updated views on diagnostic criteria, imaging, histopathology and treatment choices
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