Spelling suggestions: "subject:"antiinflammatory"" "subject:"antiiinflammatory""
341 |
Studium interleukinu 37 a jeho role u revmatoidní artritidy / Study of interleukin 37 and its role in rheumatoid arthritisJandová, Romana January 2016 (has links)
Dysregulation between pro- and anti-inflammatory cytokines activity in rheumatoid arthritis (RA) contributes to immune dysregulation, chronic inflammation and subsequent joint destruction. Interleukin-37 (IL-37) has been described as an anti-inflammatory cytokine in several autoimmune diseases. The main aim of this work was to determine the levels of IL-37 in serum and synovial fluid (SF) of RA patients and to compare them with the levels in patients with osteoarthritis (OA) and further explore the association of IL-37 with disease activity and other clinical parameters. Subsequent goal was to study its anti-inflammatory function on RA synovial fibroblasts and describe other cells types of synovial tissue contributing to its production. IL-37 levels were detected using enzyme-linked immunosorbent assay (ELISA). Synovial fibroblasts were stimulated by lipopolysaccharide (LPS) and recombinant IL-37 (rIL-37). The levels of studied genes were detected by PCR. Synovial tissues and immune cells were visualized by immunohistochemical and by immunofluorescence staining. We found increased levels of IL-37 in SF of patients with RA in comparison to OA patients. There was a significant correlation between serum and SF levels of IL-37. RA as well as OA patients showed increased levels of IL-37 in serum than in...
|
342 |
Inflammation, infections et maladies mentales : identification de biomarqueurs et applications thérapeutiques potentielles / Inflammation, infections and severe psychiatric disorders : identification of biomarkers and associated potential targeted therapeutic strategiesFond, Guillaume 08 June 2016 (has links)
Trouver des traitements efficaces dans les troubles psychiatriques majeurs (dépression majeure, trouble bipolaire et schizophrénie) est un défi de la recherche actuelle en santé mentale. Bien que des progrès considérables aient été faits dans la compréhension de la physiopathologie de ces maladies et le développement de traitements adaptés, un nombre important de patients ne répondent pas (ou pas suffisamment) aux traitements, et développent des effets secondaires. De plus, les cliniciens ne peuvent à l’heure actuelle pas prédire quel patient va répondre à un traitement précis.Nous présentons ici les résultats de nos travaux entrepris chez les patients souffrant de schizophrénie et chez les patients bipolaires. Les sujets souffrant d’un premier épisode psychotique présentent des marqueurs de perturbations inflammatoires et des marqueurs d’infections anciennes comparés aux sujets sains, en particulier une exposition au parasite Toxoplasma gondii. Ces marqueurs ne permettent toutefois pas à l’heure actuelle de prédire la réponse aux traitements conventionnels ou à des thérapies ciblées, ni l’évolution ultérieure de la maladie, et sont retrouvés pour certains aussi bien dans la schizophrénie que dans le trouble bipolaire. Dans une population de patients stabilisés souffrant de schizophrénie, 28% présentent une inflammation périphérique. Cette inflammation est fortement associée à l’obésité abdominale et au syndrome métabolique, mais également à la consommation d’antidépresseurs sans que le sens de la causalité puisse être établi à ce jour. L’obésité abdominale a été retrouvée chez 21% des patients et le syndrome métabolique chez 24%. Ces chiffres sont deux fois plus importants que dans la population Française et plus de 80% des patients ne reçoivent pas de traitements adaptés. Cette inflammation périphérique n’est pas associée à la symptomatologie positive ou négative, mais à un déclin cognitif touchant le fonctionnement intellectuel général des patients souffrant de schizophrénie.Ces résultats ouvrent la piste de nouveaux traitements. Les anti-inflammatoires ont montré leur efficacité dans les troubles psychiatriques sévères, ils nécessitent toutefois une meilleure caractérisation du profil inflammatoire de base pour identifier les patients qui pourraient être bon répondeurs, et leur efficacité pourrait être d’autant plus grande qu’ils sont administrés en début de maladie, voire avant le déclenchement du trouble. Le rapport bénéfice/risque doit également être évalué. De nombreux antipsychotiques et le valproate ont montré une activité anti-toxoplasmique qui pourrait être associée à un effet protecteur de la rechute dépressive dans le trouble bipolaire. Leur efficacité chez les patients toxopositifs souffrant de schizophrénie reste à déterminer.Les données du présent travail suggèrent qu’une proportion importante des patients souffrant de schizophrénie présente des marqueurs inflammatoires et infectieux qui pourraient orienter les traitements médicamenteux ou non-médicamenteux. La meilleure caractérisation du profil immuno-inflammatoire des patients pourrait donc permettre d’optimiser leur prise en charge et d’améliorer leur pronostic dans le cadre d’une médecine personnalisée. / Developing effective treatments in major psychiatric disorders (bipolar disorder (BP) or schizophrenia (SZ)) is crucial for the prognosis of these illnesses. While considerable efforts have been done to understand the physiopathology of these disorders, current treatments still remain ineffective (or insufficiently effective) in a high rate of patients.Subjects with first-episode psychosis have been found to have abnormal inflammatory and infectious markers compared to healthy controls, in particular higher exposure to the parasite Toxoplasma gondii. These markers cannot predict to date the illness outcomes, especially the response to conventional treatments or targeted therapies. In a community-dwelling sample of patients with schizophrenia, peripheral inflammation (as measured by abnormal CRP levels) was found in 28% of the patients. This inflammation was strongly associated with abdominal obesity and metabolic syndrome, but also with antidepressant consumption. The causal relationship has not been determined to date. Abdominal obesity was found in 21% of the patients and metabolic syndrome in 24%. This is twice the prevalence of French general population and more than 80% of the patients did not receive adequate treatments for these disturbances. Peripheral inflammation was not associated with clinical symptomatology but with cognitive impairment. Cognitive symptoms are thought to have a higher impact on the outcome of SZ than any other symptoms, and are considered as a core feature of this disorder.These results open the path for new treatments. Anti-inflammatory drugs add-on therapies have been found to improve the clinical severity of schizophrenia and bipolar disorders. Evaluating the effectiveness of neuroprotective anti-inflammatory strategies is needed in order to prevent cognitive impairment in schizophrenia. However, a better characterization of the immuno-inflammatory profile at baseline is warranted to improve the benefit/risk ratio. The literature data suggests that anti-inflammatory administration may be more effective in the two first years following the illness onset. A lot of antipsychotics and valproate have shown anti-toxoplasmic properties. Our preliminary results suggest that toxopositive patients with bipolar disorders may have less depressive relapses when administered Treatments with Antitoxoplasmic Activity (TATA). The effectiveness of TATA in toxopositive patients with bipolar disorders and schizophrenia should be confirmed in prospective studies.The present results suggest that a high rate of inflammatory and infectious disturbances have been found in patients with schizophrenia and bipolar disorders. These disturbances may orientate the choice of both pharmacological or non-pharmacological treatments. A better characterization of the immuno-inflammatory profile of these patients is needed to improve the prognosis of these illnesses on a personalized-medicine approach.
|
343 |
Modulation of heat shock proteins following the synergistic treatment of sodium salicylate and heat shock in oesophageal cancer cellsOrsmond, Colette 20 August 2012 (has links)
M.Sc. / Statistics provided by the World Health Organization state that cancer accounted for 7.9 million deaths worldwide in 2007, with numbers expected to increase to over 12 million by the year 2030. The transformation of a normal cell to a malignant tumour is known to be the result of a set of several key mutations in the genome of a normal cell, resulting in several unique properties including the evasion of programmed cell death, or apoptosis. Exacerbation of this cell death evasion can occur by overexpression of cell survival effectors such as heat shock proteins (Hsps), which are a family of highly conserved proteins that are rapidly induced in response to a variety of stresses in order to protect the cell from death. These proteins perform this function both by assisting in protein folding and therefore acting as molecular chaperones and also by directly interacting with the apoptotic machinery to prevent the initiation of cellular death. Various Hsps interfere at a range of sites in the intrinsic apoptotic pathway, both upstream of the mitochondria, and downstream at the sites of caspase activation. Similarly, Hsps also interfere at various sites in the extrinsic pathway, the caspase-independent pathways, and also function to promote the activity of survival pathways. Nonsteroidal anti-inflammatory drugs (NSAIDs) are well known for their anti-inflammatory properties via inhibition of cyclooxygenase (COX) enzymes. These drugs have also been shown to induce apoptosis in a variety of cancer cell lines as well as decrease the risk of the development of various cancers. Interestingly, NSAIDs have additionally been shown to have the curious property of activating the heat shock transcription factor (HSF1) at concentrations much higher than that required for inhibition of COX activity. The combination of NSAIDs and hyperthermia has resulted in seemingly contradictory evidence, where some studies show that this combination leads to thermotolerance and resistance to further treatments, whilst other studies have shown that this combination directly leads to cell death or indirectly sensitizes cells to subsequent stress.
|
344 |
RATIONAL DESIGN, SYNTHESIS, AND CHARACTERIZATION OF NOVEL mPGES-1 INHIBITORS AS NEXT GENERATION OF ANTI-INFLAMMATORY DRUGSZhou, Ziyuan 01 January 2017 (has links)
Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) are currently widely used as fever and pain relief in patients with arthritis and other inflammatory symptoms. NSAIDs effect by inhibiting cyclooxygenase-1 (COX-1) and/or cyclooxygenase-2 (COX-2). COX isozymes (COXs) are key enzymes in the biosynthesis of prostaglandin H2 (PGH2) from arachidonic acid (AA). It is now clear that prostaglandin E2 (PGE2), one of the downstream products of PGH2, is the main mediator in both chronic and acute inflammation. Microsomal prostaglandin E synthase (mPGES-1) is the terminal enzyme of COX-2 in the PGE2 biosynthesis pathway. Different from other two constitutively expressed PGE2 synthase (PGES), mPGES-2 and cPGES, mPGES-1 is induced by pro-inflammatory stimuli and responsible for the production of PGE2 related to inflammation, fever and pain. For these reasons, selective inhibition of mPGES-1 is expected to suppress inflammation induced PGE2 production and, therefore, will exert anti-inflammatory activity while avoid the side effects of COXs inhibitors, such as gastrointestinal (GI) toxicity, and cardiovascular events.
A combination of computational and experimental approaches was used to discovery mPGES-1 inhibitors with new scaffolds. The methods used include molecular docking, molecular dynamic simulation, molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) binding free energy calculation, and in vitro activity assays. Our large-scale structure-based virtual screening was performed on compounds in the NCI libraries, containing a total of ~260,000 compounds. 7 compounds have been determined for their IC50 values (about 300 nM to 8000 nM). What’s more, these new inhibitors of mPGES-1 identified from virtual screening did not shown significant inhibition against COX isozymes even at substantially high concentrations (e.g. 100 µM).
Rational methodology for drug design and organic synthesis were applied to generate three series of mPGES-1 inhibitors with different scaffolds. In total, about 200 compounds were synthesized and tested for their in vitro inhibition against human mPGES-1. Compounds with high potency against human mPGES-1 were further screened for their inhibition against mouse mPGES-1 and selectivity of human mPGES-1 over COXs. Several compounds were identified as submicromolar inhibitors against human mPGES-1 with high selectivity over COXs.
In general, we have successfully identified a library of compounds as potent mPGES-1 inhibitors without significant inhibition against COXs. Structure information and in vitro activity evaluation data generated from the virtual screening and the library of compounds will be used to guide future design and synthesis of the mPGES-1 inhibitors.
|
345 |
Biological activities of extracts and isolated compounds from Bauhinia galpinii (Fabaceae) and Combretum vendae (Combretaceae) as potential antidiarrhoeal agentsAhmed, Aroke Shahid 27 February 2013 (has links)
Diarrhoea is one of the killer diseases resulting from the dehydration and loss of electrolytes through profuse and excessive excretion of loose stool. The pathoaetiologies include infections, intestinal inflammation, imbalanced intestinal oxidative homeostasis and altered motility. Treatment with oral rehydration therapy (ORT) is a key intervention especially in secretory diarrhoea as supportive therapy. Symptomatic and non-symptomatic therapies directed at treating the intestinal tissues are available. However, these conventional treatments are still not sufficient in curing diarrhoea due to their associated hazards such as the development and spread of drugresistant pathogens, changes in normal intestinal bacteria flora and potential chronic toxicity. Therapies targeted at intestinal tissue include antimotility and antisecretory agents have adverse effects such as addictiveness, constipation and fatal ischaemic colitis. Many ethnopharmacological and ethnobotanical therapies for treating diarrhoea exist among different cultures. The aims of this study were to evaluate the biological activities of plant extracts against some diarrhoeal pathophysiologies. A literature search in English of published articles and books that discussed ethnobotanical uses of medicinal plants in southern Africa was conducted. A list of 230 medicinal plants used in South African traditional medicines for treating diarrhoea and associated complications was created. The list included family, genus, species, biological activities and bioactive isolates as well as the remedies for diarrhoea. Twenty seven species were selected to evaluate for antimicrobial, antioxidant and anti-inflammatory activities. Safety of the plants was determined by determining the cytotoxicity of the crude extracts against Vero African green monkey kidney cell lines using a standard method. Motility effects of Bauhinia galpinii (BGE) and <i<Combretum vendae (CVE) were determined by modulation of the contractility process of the isolated rat ileum induced by spasmogens. Phenolic compositions of the crude extract were determined using various standard methods and finally bioactivity guided isolation of antimicrobial and antioxidant compounds from BGE and CVE were carried out using open column chromatography. Identification and characterization of the isolated compounds was achieved by NMR, El-MS and UV spectroscopy. The non-polar fractions had good antimicrobial activities with MIC ranged between 19 - 1250 μg/ml while the polar fraction had moderate antimicrobial activities with MIC ranged between 39 - >2500 μg/ml. In general the non-polar fractions had a higher antimicrobial activity. The crude extracts contained wide range phenolic compounds with a total phenolic (7 4.91 ±1.26 to 467.04±15.82 mg GAE/g plant material), and total flavonoids (11.27±3.37 to 176±5.96 mg EQ/g plant material). The antioxidant activities were concentrated and potentiated in the polar fractions. The non-polar fractions had poor antioxidant activities with EC50 values ranging from 0.21 ±0.03 to 303.65±3.84 μg/ml for DPPH radical scavenging and 0.43±0.03 to 1709±91.44 μg/ml for ABTS radical scavenging. The crude extracts had selective COX-1 inhibitory activities ranging between 41.70 to 84.61% and had no COX-2 inhibitory activity. All the extracts tested had 15-LOX inhibitory capacity with LC50 values ranging between 0.86±0.27 and 111.44±37.28 1-μg/ml. The cytotoxicity results indicated a wide variation in toxic potential of the crude extracts with LC50 values ranging from 3.51 to 741.901-μg/ml. The BGE extracts had dual activities as spasmolytic by stimulating the spontaneous contractility and also agonised contractions induced by spasmogens but it inhibited K+ induced contraction. CVE had spasmodic activities through a multiple mechanisms inhibiting contractions induced by spasmogens and K+ in a dosedependent manner. Several bioactive xompoundswere isolated from the <i<Combretum vendae leaves, There were triterpenoids (ursol-12-en-28-oic acid, mixtures of corosolic acid and maslinic acid, and asiatic acid and arjunolic acid) as well as bibenzyls combretastatin 85-0-2'-β-D-glucopyranoside, combretastatin 81-0-2'-β-Dglucopyranoside and a flavonoid (apigenin) .. From Bauhinia galpinii the following bioactive compounds were isolated and characterized: β-3 ethoxy sitosterol, one new flavone (5, 7, 4' 5' tetrahydroxy-2'-methoxyflavone (isoetin 2'-methyl ether) or 5, 7, 2' 5' tetrahydroxy-4'-methoxyflavone (isoetin 4'-methyl ether)), 3, 5, 7, 3', 4'-pentahydroxyflavone and 3, 5, 7, 3', 4', 5'hexahydroxyflavone, quercetin-3-0-β-galactopyranoside and myriceti n-3-0-β-galactopyranoside The extraction protocol used in this work potentiated the antimicrobial activities in the non-polar fractions while antioxidant activities were potentiated in the polar fractions. This indicated that using polar solvents as extractant for treating infectious diarrhoea may not be quite effective unless some other antidiarrhoeal mechanisms are involved. Therefore, mixture of organic solvent (ethanol) and water can be recommended for broad-based activity. Bauhinia galpinii extracts had a dual- mechanism of action (prokinetic and relaxant) on gastro-intestinal motility, depending on the prevalent patho-physiological condition and Combretum vendae mediated spasmolytic effects on isolated rat ileum through multiple inhibitions of a wide range of contractile stimuli. Hence, the presence of multiple acting spasmolytic activities in the plant extract might be contributing towards its effectiveness in treating diarrhoea and abdominal spasm. The uses of these plants in traditional medicine need to be monitored closely because of the selective inhibition of COX-1 and its associated GIT injury, and the high toxicity potential of some of the extracts. Further work evaluating the antidiarrhoea mechanisms, identification and isolation of bioactive compounds, sub-acute and acute toxicity of the plant extracts is recommended. / Thesis (PhD)--University of Pretoria, 2013. / Paraclinical Sciences / unrestricted
|
346 |
Traumeel S : the sportsman's answer to enhanched exercise performance and the overtraining syndrome?Jordaan, Dirk Pieter 20 April 2007 (has links)
Research indicates that eccentric exercise is associated with delayed onset of muscle soreness (DOMS). The symptoms associated with DOMS is similar to other inflammatory conditions e.g. pain, swelling and tissue damage. The DOMS as a reaction to the muscle damage is accompanied by changes in cytokines, leukocytes and other markers of inflammation. Prolonged exercise training without adequate rest and nutrition can lead to chronic inflammation and altered cytokine production patterns, which could result in overtraining. Methodology The study included actively participating marathon runners and consisted of two groups, a control group (n = 24 athletes) and an experimental group taking Traumeel S (n = 26 athletes), assigned in a double-blind fashion. Subjects made use of the treatment protocol for a period of seven days and followed their normal training program with no additional training. DOMS was induced on day eight when subjects ran downhill at 75% of peak treadmill running speed (PTRS) for 45 minutes at a gradient of –10% with ratings of perceived exertion (RPE), perceived pain (RPP) and heart rate was measured during the run. After the DOMS was induced subjects reported for blood samples for serum creatine kinase (CK), serum cortisol and a differential white blood cell count was taken at the same time for four days after DOMS was induced. Results The t-test for independent groups was used to determine the statistical differences between the two groups and for inter-group analysis. The results showed minor and predominantly insignificant changes in CK-, basophil-, eosinophil- and lymphocyte-counts. The cortisol levels in the treated group were higher compared to the placebo group at 48-, 72- and 96-hours post-exercise. The treated subjects’ mean monocyte count fell significantly on the first day of recovery and remained significantly lower for the four days post-exercise. Conclusions The increased cortisol concentrations can assist the immune system to shut of the acute inflammatory reaction associated with DOMS and in so doing reduce exercise induced muscle damage and inflammation. The decreased monocyte counts will reduce blood vessel permeability and swelling, fewer pain receptors will be stimulated because of lower PGE2 levels associated with decreased monocyte activation. Secondary, muscle damage that can amongst others be associated with increased monocytic activity, will be limited. Additional blood tests and performance testing are needed to confirm and substantiate the findings of the research. / Dissertation (MA (Human Movement Sciences)--University of Pretoria, 2007. / Biokinetics, Sport and Leisure Sciences / unrestricted
|
347 |
Biological activities of extracts and isolated compounds from Bauhinia galpinii (Fabaceae) and Combretum vendae (Combretaceae) as potential antidiarrhoeal agentsAhmed, Aroke Shahid 07 May 2012 (has links)
Diarrhoea is one of the killer diseases resulting from the dehydration and loss of electrolytes through profuse and excessive excretion of loose stool. The pathoaetiologies include infections, intestinal inflammation, imbalanced intestinal oxidative homeostasis and altered motility. Treatment with oral rehydration therapy (ORT) is a key intervention especially in secretory diarrhoea as supportive therapy. Symptomatic and non-symptomatic therapies directed at treating the intestinal tissues are available. However, these conventional treatments are still not sufficient in curing diarrhoea due to their associated hazards such as the development and spread of drugresistant pathogens, changes in normal intestinal bacteria flora and potential chronic toxicity. Therapies targeted at intestinal tissue include antimotility and antisecretory agents have adverse effects such as addictiveness, constipation and fatal ischaemic colitis. Many ethnopharmacological and ethnobotanical therapies for treating diarrhoea exist among different cultures. The aims of this study were to evaluate the biological activities of plant extracts against some diarrhoeal pathophysiologies. A literature search in English of published articles and books that discussed ethnobotanical uses of medicinal plants in southern Africa was conducted. A list of 230 medicinal plants used in South African traditional medicines for treating diarrhoea and associated complications was created. The list included family, genus, species, biological activities and bioactive isolates as well as the remedies for diarrhoea. Twenty seven species were selected to evaluate for antimicrobial, antioxidant and anti-inflammatory activities. Safety of the plants was determined by determining the cytotoxicity of the crude extracts against Vero African green monkey kidney cell lines using a standard method. Motility effects of Bauhinia galpinii (BGE) and Combretum vendae (CVE) were determined by modulation of the contractility process of the isolated rat ileum induced by spasmogens. Phenolic compositions of the crude extract were determined using various standard methods and finally bioactivity guided isolation of antimicrobial and antioxidant compounds from BGE and CVE were carried out using open column chromatography. Identification and characterization of the isolated compounds was achieved by NMR, EI-MS and UV spectroscopy. The non-polar fractions had good antimicrobial activities with MIC ranged between 19 – 1250 μg/ml while the polar fraction had moderate antimicrobial activities with MIC ranged between 39 - >2500 μg/ml. In general the non-polar fractions had a higher antimicrobial activity. The crude extracts contained wide range phenolic compounds with a total phenolic (74.91±1.26 to 467.04±15.82 mg GAE/g plant material), and total flavonoids (11.27±3.37 to 176±5.96 mg EQ/g plant material). The antioxidant activities were concentrated and potentiated in the polar fractions. The non-polar fractions had poor antioxidant activities with EC50 values ranging from 0.21±0.03 to 303.65±3.84 μg/ml for DPPH radical scavenging and 0.43±0.03 to 1709±91.44 μg/ml for ABTS radical scavenging. The crude extracts had selective COX-1 inhibitory activities ranging between 41.70 to 84.61% and had no COX-2 inhibitory activity. All the extracts tested had 15-LOX inhibitory capacity with LC50 values ranging between 0.86±0.27 and 111.44±37.28 μg/ml. The cytotoxicity results indicated a wide variation in toxic potential of the crude extracts with LC50 values ranging from 3.51 to 741.90μg/ml. The BGE extracts had dual activities as spasmolytic by stimulating the spontaneous contractility and also agonised contractions induced by spasmogens but it inhibited K+ induced contraction. CVE had spasmodic activities through a multiple mechanisms inhibiting contractions induced by spasmogens and K+ in a dosedependent manner. Several bioactive xompoundswere isolated from the Combretum vendee leaves, There were triterpenoids (ursol-12-en-28-oic acid, mixtures of corosolic acid and maslinic acid, and asiatic acid and arjunolic acid) as well as bibenzyls combretastatin B5-O-2’-β-D-glucopyranoside, combretastatin B1-O-2’-β-D glucopyranoside and a flavonoid (apigenin). From Bauhinia galpinii the following bioactive compounds were isolated and characterized: P-3 ethoxy sitosterol, one new flavone (5, 7, 4’ 5’ tetrahydroxy-2’-methoxyflavone (isoetin 2’-methyl ether) or 5, 7, 2’ 5’ tetrahydroxy-4’-methoxyflavone (isoetin 4’-methyl ether)), 3, 5, 7, 3’, 4’-pentahydroxyflavone and 3, 5, 7, 3’, 4’, 5’- hexahydroxyflavone, quercetin-3-O-β-galactopyranoside and myricetin-3-O-β-galactopyranoside. The extraction protocol used in this work potentiated the antimicrobial activities in the non-polar fractions while antioxidant activities were potentiated in the polar fractions. This indicated that using polar solvents as extractant for treating infectious diarrhoea may not be quite effective unless some other antidiarrhoeal mechanisms are involved. Therefore, mixture of organic solvent (ethanol) and water can be recommended for broad-based activity. Bauhinia galpinii extracts had a dual- mechanism of action (prokinetic and relaxant) on gastro-intestinal motility, depending on the prevalent patho-physiological condition and Combretum vendee mediated spasmolytic effects on isolated rat ileum through multiple inhibitions of a wide range of contractile stimuli. Hence, the presence of multiple acting spasmolytic activities in the plant extract might be contributing towards its effectiveness in treating diarrhoea and abdominal spasm. The uses of these plants in traditional medicine need to be monitored closely because of the selective inhibition of COX-1 and its associated GIT injury, and the high toxicity potential of some of the extracts. Further work evaluating the antidiarrhoea mechanisms, identification and isolation of bioactive compounds, sub-acute and acute toxicity of the plant extracts is recommended. / Thesis (PhD)--University of Pretoria, 2012. / Paraclinical Sciences / unrestricted
|
348 |
The toxicity, pharmacokinetics, anti-inflammatory and anti-tumour properties of a methotrexate polymerSayed, Sharfuddin Sakil 12 May 2010 (has links)
A major effort to develop anticancer drugs through both empiric screening and rational design of new compounds has been under way for over 30 years (Katzung, 2004). In recent years, research and development in the field of sitespecific drug therapy has progressed significantly. Safe and non-toxic formulations of cytotoxic drugs based on polymers with their improved sitespecific delivery and effective activation to biologically active cytotoxic compounds at the targeted tumours have become a promising approach to cancer therapy. Drug delivery systems based on polymer micelles, coated microand nanoparticles, liposomes and various pro-drug systems including watersoluble polymer–drug conjugates and immunoconjugates have been prepared and extensively studied as novel drug delivery systems designed for cancer chemotherapy. Amongst these drug delivery systems that enable specific drug delivery and release, water-soluble polymer–drug conjugates rank among the most promising, versatile and efficient systems. This dissertation reviews the preclinical testing and pharmacokinetic study of D85, a novel water-soluble macromolecular pro-drug that is a polymer with pHcontrolled methotrexate (MTX) release with potential for treatment of cancer in humans (Ulbrich&Subr, 2004). As MTX is also indicated in low doses for the treatment of chronic inflammatory conditions, the polymer was further tested in an acute inflammatory model to determine whether the polymer would be more effective than MTX in controlling inflammation. The objective of this study was to compare the potency and efficacy of D85 to MTX. D85, a MTX conjugated polymeric lead compound, was designed and synthesised as a potential anti-neoplastic and anti-inflammatory agent. It was initially tested in vitro on three different cancer cell lines where selective toxicity towards the cancer cell cultures compared to primary cell cultures and greater toxicity than MTX was observed. The initial in vitro tests showed very promising results with D85 demonstrating approximately 300 times greater cytotoxicity than MTX against a colon cancer cell line (COLO 320 DM). This high cytotoxic effect warranted further investigation in an in vivo colon cancer tumour model. An induced murine tumour model of COLO 320 DM was successfully developed in nude mice, and the anti-tumour efficacy of D85 tested in this model. The maximum tolerated dose of D85 was established by carrying out an in vivo dose ranging toxicity test in BALB/c mice. The anti-inflammatory effects of D85 were also determined using the carrageenan-induced paw oedema model in rats where carrageenan was injected into a footpad of a rat causing acute oedema, which was measured using a water displacement plethysmometer. D85 was found to exacerbate the inflammatory response. Finally, the pharmacokinetic parameters of MTX and D85 were assessed using a LC/MS/MS method specifically developed and validated to determine low concentrations of MTX in small volumes of plasma. This new method made use of online solid phase extraction and sample cleanup on 2μl injections of diluted plasma allowing an entire pharmacokinetics study to be completed on an individual rat. Fairly similar pharmacokinetics were determined from both compounds. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Pharmacology / unrestricted
|
349 |
The identification of bio-available and active components in oxihumateCromarty, Allan Duncan 13 June 2005 (has links)
Please read the abstract in the section 00front of this document / Thesis (PhD (Pharmacology))--University of Pretoria, 2005. / Pharmacology / unrestricted
|
350 |
Coxibs and traditional NSAIDs : systematic overviews of the randomised evidence for the effects of traditional non-steroidal anti-inflammatory drugs and selective inhibitors of cyclo-oxygenase-2 on vascular and upper gastrointestinal outcomesBhala, Neeraj January 2013 (has links)
No description available.
|
Page generated in 0.0762 seconds