745 research outputs found
Controlled release from zein matrices: Interplay of drug hydrophobicity and pH
Purpose: In earlier studies, the corn protein zein is found to be suitable as a sustained release agent, yet the range of drugs for which zein has been studied remains small. Here, zein is used as a sole excipient for drugs differing in hydrophobicity and isoelectric point: indomethacin, paracetamol and ranitidine. Methods: Caplets were prepared by hot-melt extrusion (HME) and injection moulding (IM). Each of the three model drugs were tested on two drug loadings in various dissolution media. The physical state of the drug, microstructure and hydration behaviour were investigated to build up understanding for the release behaviour from zein based matrix for drug delivery. Results: Drug crystallinity of the caplets increases with drug hydrophobicity. For ranitidine and indomethacin, swelling rates, swelling capacity and release rates were pH dependent as a consequence of the presence of charged groups on the drug molecules. Both hydration rates and release rates could be approached by existing models. Conclusion: Both the drug state as pH dependant electrostatic interactions are hypothesised to influence release kinetics. Both factors can potentially be used factors influencing release kinetics release, thereby broadening the horizon for zein as a tuneable release agent
TO INVESTIGATE AND ASSES WHY SOME FOOD/ DIETARY SUPPLEMENTS ARE HEALTH HAZARDOUS
Toxic ingredients of Pharmaceutical as well as Food grade food supplements / Dietary Supplement are Pygeum, Caffeine / Caffeine extract, Omega 3 fatty acid (source fish oil, flaxseed oil, or cod liver oil), Ephedrine (Ephedra sinica) , Usnic acid, Kava-Kava (Piper methysticum), Gugulipid (Comiphora mukul), Liquorice (Glycyrrhiza glabra), Ginseng (Panax ginseng, Panax japonicus, Panax trifolius, Panax zingiberensis, Panax bipinnatifidus), St. John's wort (Hypericum perforatum) etc. Caffeine (1,3,7-trimethylxanthine) is an alkaloid of the methylxanthine family known as a central nervous system stimulant through its adenosine antagonist action. Caffeine is a naturally found in the leaves, seeds and/or fruits of at least 63 plant species worldwide. Caffeine produces psychoactive responses (alertness, mood change), neurological condition (infant hyperactivity, Parkinson’s disease), metabolic disorders (diabetes, gallstones), and gonad and liver function. However, high doses may produce negative effects in some sensitive individuals, including anxiety, tachycardia and insomnia recommended upper limits of caffeine for healthy adults below 300-500 mg daily, pregnant women must stay below 150-200 mg daily and children should stay below 50 mg daily. Amounts exceeding 700 milligrams of caffeine can be dangerous. Key words: Caffeine, CNS stimulan
Prostate cancer cell malignancy via modulation of HIF-1 alpha pathway with isoflurane and propofol alone and in combination
BACKGROUND: Surgery is considered to be the first line treatment for solid tumours. Recently, retrospective studies reported that general anaesthesia was associated with worse long-term cancer-free survival when compared with regional anaesthesia. This has important clinical implications; however, the mechanisms underlying those observations remain unclear. We aim to investigate the effect of anaesthetics isoflurane and propofol on prostate cancer malignancy. METHODS: Prostate cancer (PC3) cell line was exposed to commonly used anaesthetic isoflurane and propofol. Malignant potential was assessed through evaluation of expression level of hypoxia-inducible factor-1α (HIF-1α) and its downstream effectors, cell proliferation and migration as well as development of chemoresistance. RESULTS: We demonstrated that isoflurane, at a clinically relevant concentration induced upregulation of HIF-1α and its downstream effectors in PC3 cell line. Consequently, cancer cell characteristics associated with malignancy were enhanced, with an increase of proliferation and migration, as well as development of chemoresistance. Inhibition of HIF-1α neosynthesis through upper pathway blocking by a PI-3K-Akt inhibitor or HIF-1α siRNA abolished isoflurane-induced effects. In contrast, the intravenous anaesthetic propofol inhibited HIF-1α activation induced by hypoxia or CoCl(2). Propofol also prevented isoflurane-induced HIF-1α activation, and partially reduced cancer cell malignant activities. CONCLUSIONS: Our findings suggest that modulation of HIF-1α activity by anaesthetics may affect cancer recurrence following surgery. If our data were to be extrapolated to the clinical setting, isoflurane but not propofol should be avoided for use in cancer surgery. Further work involving in vivo models and clinical trials is urgently needed to determine the optimal anaesthetic regimen for cancer patients
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Motion and pattern cortical potentials in adults with high-functioning autism spectrum disorder
Purpose: Autism spectrum disorder (ASD) is a condition in which visual perception to both static and moving stimuli is altered. The aim of this study was to investigate the early cortical responses of subjects with ASD to simple patterns and moving radial rings using visual evoked potentials (VEPs).
Methods: Male ASD participants (n = 9) and typically developing (TD) individuals (n = 7) were matched for full, performance and verbal IQ (p > 0.263). VEPs were recorded to the pattern reversing checks of 50′ side length presented with Michelson contrasts of 98 and 10 % and to the onset of motion—either expansion or contraction of low-contrast concentric rings (33.3 % duty cycle at 10 % contrast).
Results: There were no significant differences between groups in the VEPs elicited by pattern reversal checkerboards of high (98 %) or low (10 %) contrast. The ASD group had a significantly larger N160 peak (1.85 x) amplitude to motion onset VEPs elicited by the expansion of radial rings (p = 0.001). No differences were evident in contraction VEP peak amplitudes nor in the latencies of the motion onset N160 peaks. There was no evidence of a response that could be associated with adaptation to the motion stimulus in the interstimulus interval following an expansion or contraction phase of the rings.
Conclusion: These data support a difference in processing of motion onset stimuli in this adult high-functioning ASD group compared to the TD group
Unlocking the potential of informal healthcare providers in tuberculosis care: Insights from India
The complex interplay between endoplasmic reticulum stress and the NLRP3 inflammasome: a potential therapeutic target for inflammatory disorders.
Inflammation is the result of a complex network of cellular and molecular interactions and mechanisms that facilitate immune protection against intrinsic and extrinsic stimuli, particularly pathogens, to maintain homeostasis and promote tissue healing. However, dysregulation in the immune system elicits excess/abnormal inflammation resulting in unintended tissue damage and causes major inflammatory diseases including asthma, chronic obstructive pulmonary disease, atherosclerosis, inflammatory bowel diseases, sarcoidosis and rheumatoid arthritis. It is now widely accepted that both endoplasmic reticulum (ER) stress and inflammasomes play critical roles in activating inflammatory signalling cascades. Notably, evidence is mounting for the involvement of ER stress in exacerbating inflammasome-induced inflammatory cascades, which may provide a new axis for therapeutic targeting in a range of inflammatory disorders. Here, we comprehensively review the roles, mechanisms and interactions of both ER stress and inflammasomes, as well as their interconnected relationships in inflammatory signalling cascades. We also discuss novel therapeutic strategies that are being developed to treat ER stress- and inflammasome-related inflammatory disorders
Connecting various types of cyclic contractions and contractive self-mappings with Hardy-Rogers self-mappings
RosettaRemodel: A Generalized Framework for Flexible Backbone Protein Design
We describe RosettaRemodel, a generalized framework for flexible protein design that provides a versatile and convenient interface to the Rosetta modeling suite. RosettaRemodel employs a unified interface, called a blueprint, which allows detailed control over many aspects of flexible backbone protein design calculations. RosettaRemodel allows the construction and elaboration of customized protocols for a wide range of design problems ranging from loop insertion and deletion, disulfide engineering, domain assembly, loop remodeling, motif grafting, symmetrical units, to de novo structure modeling
Cellular changes in boric acid-treated DU-145 prostate cancer cells
Epidemiological, animal, and cell culture studies have identified boron as a chemopreventative agent in prostate cancer. The present objective was to identify boron-induced changes in the DU-145 human prostate cancer cell line. We show that prolonged exposure to pharmacologically-relevant levels of boric acid, the naturally occurring form of boron circulating in human plasma, induces the following morphological changes in cells: increases in granularity and intracellular vesicle content, enhanced cell spreading and decreased cell volume. Documented increases in β-galactosidase activity suggest that boric acid induces conversion to a senescent-like cellular phenotype. Boric acid also causes a dose-dependent reduction in cyclins A–E, as well as MAPK proteins, suggesting their contribution to proliferative inhibition. Furthermore, treated cells display reduced adhesion, migration and invasion potential, along with F-actin changes indicative of reduced metastatic potential. Finally, the observation of media acidosis in treated cells correlated with an accumulation of lysosome-associated membrane protein type 2 (LAMP-2)-negative acidic compartments. The challenge of future studies will be to identify the underlying mechanism responsible for the observed cellular responses to this natural blood constituent
Average arterial input function for quantitative dynamic contrast enhanced magnetic resonance imaging of neck nodal metastases
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