283 resultados para Doxorubicin -- therapeutic use
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Arachidonic acid metabolism through cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P-450 epoxygenase (EPOX) pathways is responsible for the formation of biologically active eicosanoids, including prostanoids, leukotrienes, hydroxyeicosatetraenoic acid, epoxyeicosatrienoic acid and hydroperoxyeicosatetraenoic acids. Altered eicosanoid expression levels are commonly observed during tumour development and progression of a range of malignancies, including non-small cell lung cancer (NSCLC). Arachidonic acid-derived eicosanoids affect a range of biological phenomena to modulate tumour processes such as cell growth, survival, angiogenesis, cell adhesion, invasion and migration and metastatic potential. Numerous studies have demonstrated that eicosanoids modulate NSCLC development and progression, while targeting these pathways has generally been shown to inhibit tumour growth/progression. Modulation of these arachidonic acid-derived pathways for the prevention and/or treatment of NSCLC has been the subject of significant interest over the past number of years, with a number of clinical trials examining the potential of COX and LOX inhibitors in combination with traditional and novel molecular approaches. However, results from these trials have been largely disappointing. Furthermore, enthusiasm for the use of selective COX-2 inhibitors for cancer prevention/treatment waned, due to their association with adverse cardiovascular events in chemoprevention trials. While COX and LOX targeting may both retain promise for NSCLC prevention and/or treatment, there is an urgent need to understand the downstream signalling mechanisms through which these and other arachidonic acid-derived signalling pathways mediate their effects on tumourigenesis. This will allow for development of safer and potentially more effective strategies for NSCLC prevention and/or treatment. Chemoprevention studies with PGI2 analogues have demonstrated considerable promise, while binding to/signalling through PGE2 receptors have also been the subject of interest for NSCLC treatment. In this chapter, the role of the eicosanoid signalling pathways in non-small cell lung cancer will be discussed. In particular, the effect of the eicosanoids on tumour cell proliferation, their roles in induction of cell death, effects on angiogenesis, migration, invasion and their regulation of the immune response will be assessed, with signal transduction pathways involved in these processes also discussed. Finally, novel approaches targeting these arachidonic acid-derived eicosanoids (using pharmacological or natural agents) for chemoprevention and/or treatment of NSCLC will be outlined. Elucidating the molecular mechanisms underlying the effects of specific or general arachidonic acid pathway modulators may lead to the design of biologically and pharmacologically targeted therapeutic strategies for NSCLC prevention/treatment, which may be used alone or in combination with conventional therapies.
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Systemic lupus erythematosus (SLE) is distinct among autoimmune diseases because of its association with circulating autoantibodies reactive against host DNA. The precise role that anti-DNA antibodies play in SLE pathophysiology remains to be elucidated, and potential applications of lupus autoantibodies in cancer therapy have not previously been explored. We report the unexpected finding that a cell-penetrating lupus autoantibody, 3E10, has potential as a targeted therapy for DNA repair–deficient malignancies. We find that 3E10 preferentially binds DNA single-strand tails, inhibits key steps in DNA single-strand and double-strand break repair, and sensitizes cultured tumor cells and human tumor xenografts to DNA-damaging therapy, including doxorubicin and radiation. Moreover, we demonstrate that 3E10 alone is synthetically lethal to BRCA2-deficient human cancer cells and selectively sensitizes such cells to low-dose doxorubicin. Our results establish an approach to cancer therapy that we expect will be particularly applicable to BRCA2-related malignancies such as breast, ovarian, and prostate cancers. In addition, our findings raise the possibility that lupus autoantibodies may be partly responsible for the intrinsic deficiencies in DNA repair and the unexpectedly low rates of breast, ovarian, and prostate cancers observed in SLE patients. In summary, this study provides the basis for the potential use of a lupus anti-DNA antibody in cancer therapy and identifies lupus autoantibodies as a potentially rich source of therapeutic agents.
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Cancer can be defined as a deregulation or hyperactivity in the ongoing network of intracellular and extracellular signaling events. Reverse phase protein microarray technology may offer a new opportunity to measure and profile these signaling pathways, providing data on post-translational phosphorylation events not obtainable by gene microarray analysis. Treatment of ovarian epithelial carcinoma almost always takes place in a metastatic setting since unfortunately the disease is often not detected until later stages. Thus, in addition to elucidation of the molecular network within a tumor specimen, critical questions are to what extent do signaling changes occur upon metastasis and are there common pathway elements that arise in the metastatic microenvironment. For individualized combinatorial therapy, ideal therapeutic selection based on proteomic mapping of phosphorylation end points may require evaluation of the patient's metastatic tissue. Extending these findings to the bedside will require the development of optimized protocols and reference standards. We have developed a reference standard based on a mixture of phosphorylated peptides to begin to address this challenge.
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Purpose To determine the prescribed drug-utilisation pattern for six common chronic conditions in adult South Africans in a cross-sectional survey. Methods 13 826 randomly selected participants, 15 years and older, were surveyed by trained fieldworkers at their homes in 1998. Questionnaires included socio-demographic, chronic-disease and drug-use data. The prescribed drugs were recorded from participants' medication containers. The Anatomical Therapeutic Classification (ATC) code of the drugs for tuberculosis (TB), diabetes, hypertension, hyperlipidaemia, other atherosclerosis-related conditions, such as heart conditions or cerebrovascular accidents (CVA), and asthma or chronic obstructive pulmonary disease (COPD), was recorded. The use of logistic regression analyses identified the determinants of those patients who used prescription medication for these six conditions. Results 18.4% of the women and 12.5% of the men used drugs for the six chronic conditions. Men used drugs most frequently for hypertension (50.9%) and asthma or chronic bronchitis (24.3%), while in women it was for hypertension (59.9%) and diabetes (17.5%). The logistic regression analyses showed that women, wealthier and older people, and those with medical insurance used these chronic-disease drugs more frequently compared to men, younger or poor people, or those without medical insurance. The African population group used these drugs less frequently than any other ethnic group. The inappropriate use of methyldopa was found for 14.8% of all antihypertensive drugs, while very few people used aspirin. Conclusions The methodology of this study provides a means of ascertaining the chronic-disease drug-utilisation pattern in national health surveys. The pattern described, suggests an inequitable use of chronic-disease drugs and inadequate use of some effective drugs to control the burden of chronic diseases in South Africa. Copyright © 2004 John Wiley & Sons, Ltd.
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This article considers the origins and the development of the defence of experimental use in patent law - the ’freedom to tinker'. It explores the impact of such an exemption upon a number of important industries - such as agriculture, biotechnology, and pharmaceutical drugs. This article takes a comparative approach in its analysis of patent law and experimental use. It highlights the competing norms, and lack of harmonization between a number of jurisdictions - including the United States, the European Union, and Australia. Section 2 provides a critique of the development of the common law defence of experimental use in the United States. It considers a series of precedents - including Roche Products Inc v Bolar Pharmaceuticals, Madey v Duke University, Integra Lifesciences I Ltd v Merck KgaA, and Applera v MJ Research. Section 3 explores the operation of patent law and experimental use in European jurisdictions. It looks at a number of significant precedents in the United Kingdom, the Netherlands, France, Italy, and Germany. Section 4 considers the policy debate in a number of forums over the defence of experimental use in Australia. It examines the controversy over Genetic Technologies Limited asking research organisations to obtain a licence in respect of its patents associated with non-coding DNA and genomic mapping. It also considers the inquiries of the Australian Law Reform Commission and the Advisory Council on Intellectual Property, as well as the impact of the TRIPS Agreement and the Australia-United States Free Trade Agreement. The conclusion contends that there is a need for a broad-based defence of experimental use for all the member states of the Organisation for Economic Co-operation and Development.
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Objective Contemporary research demonstrates the feasibility of assessing therapeutic performance of trainee-therapists through the use of objective measures of client treatment outcome. Further, significant variation between individual therapists based on their client treatment outcomes has been demonstrated. This study sets out to determine whether a reliable composite measure of therapeutic efficiency, effectiveness and early dropout can be developed and used to objectively compare trainee-therapists against each other. Design and methods Treatment outcomes of 611 clients receiving treatment from 58 trainee-therapists enrolled in a professional training programme were tracked with the OQ-45.2 over a 6-year period to assess therapeutic efficiency, therapeutic effectiveness and early client dropout. Results Significant variation between trainee-therapists was observed for each index. Findings of a moderately strong correlation between therapeutic efficiency and effectiveness enabled the ranking of trainee-therapists based upon a composite measure of these indexes. A non-significant correlation was found between early client dropout and measures of therapeutic effectiveness and efficiency. Conclusions The findings stress the importance of utilizing objective measures to track the treatment outcomes. Despite all trainee-therapists being enrolled in the same training programme, significant variation between trainee-therapists' therapeutic efficiency and effectiveness was found to exist. Practitioner points Developing of potential benchmarking tools that enable trainee-therapists, supervisors and educational institutions to quickly assess therapeutic performance can become part of a holistic assessment of a trainee-therapist's clinical development. Despite an inherent optimistic belief that therapists do not cause harm, there appears to be a small and significant proportion of trainee-therapists who consistently evidence little therapeutic change. Considerable variability in trainee-therapists' therapeutic efficiency and effectiveness can exist in the one training programme. Early client dropout may not be associated with therapists' therapeutic effectiveness and efficiency.
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On the basis of local data, we write in support of the conclusions of Smith and Ahern that current Pharmaceu- tical Benefits Scheme (PBS) criteria for tumour necrosis factor (TNF)-a inhibitors in ankylosing spondylitis (AS) are not evidence-based. 1 As a prerequisite to the appropriate use of biological therapy in AS, three aspects of the disease need to be defined: (i) diagnosis, (ii) activity and (iii) therapeutic failure (Table 1)....
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Stress is a major driving force in alcohol use disorders (AUDs). It influences how much one consumes, craving intensity and whether an abstinent individual will return to harmful alcohol consumption. We are most vulnerable to the effects of stress during early development, and exposure to multiple traumatic early life events dramatically increases the risk for AUDs. However, not everyone exposed to early life stress will develop an AUD. The mechanisms determining whether an individual’s brain adapts and becomes resilient to the effects of stress or succumbs and is unable to cope with stress remain elusive. Emerging evidence suggests that neuroplastic changes in the nucleus accumbens (NAc) following early life stress underlie the development of AUDs. This review discusses the impact of early life stress on NAc structure and function, how these changes affect cholinergic signaling within the mesolimbic reward pathway and the role nicotinic acetylcholine receptors (nAChRs) play in this process. Understanding the neural pathways and mechanism determining stress resilience or susceptibility will improve our ability to identify individuals susceptible to developing AUDs, formulate cognitive interventions to prevent AUDs in susceptible individuals and to elucidate and enhance potential therapeutic targets, such as the nAChRs, for those struggling to overcome an AUD.
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Background: Internationally, the use of dietary supplements has been growing rapidly. Patient support for pharmacist sales of nutritional and dietary supplements is also strong. The increase in demand for nutritional and dietary supplements and subsequent advice about these products, however, makes it necessary that pharmacists maintain a contemporary knowledge of the area. Aim of review: This systematic review was conducted to examine the current evidence regarding the level of the nutritional and dietary supplement knowledge of community pharmacists and their understanding of their therapeutic effects. Method: Electronic databases including Medline, Scopus, Embase, CINAHL, Scifinder and the Cochrane Controlled Trials Register were searched. Studies assessing nutritional knowledge of pharmacists in community pharmacies were eligible for inclusion. All languages and study designs were considered. Study results were analysed and pharmacist knowledge scores were given out of 100Â . Results: From 5594 studies identified, nine met the inclusion criteria. Each study tested pharmacist knowledge with predetermined questions calculating results as the number of questions answered correctly. These knowledge scores were converted to a percentage score for the purpose of this paper. The median knowledge score across all papers was 64%. A lack of studies assessing community pharmacist's knowledge of commonly sold vitamins and minerals was observed. Conclusions Global community pharmacist knowledge of dietary supplements appears to be poor. Community pharmacists have an professional responsibility to provide accurate health information about dietary supplements as they do for any other therapies they provide to patients. Further research including that which assesses pharmacist's therapeutic knowledge of commonly sold vitamins and minerals is suggested.
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There is an increasing awareness of the therapeutic potential for combining immune-based therapies with chemotherapy in the treatment of malignant diseases, but few published studies evaluate possible cytotoxic synergies between chemotherapy and cytotoxic immune cells. Human Vα24 +/Vβ11+ NKT cells are being evaluated for use in cell-based immunotherapy of malignancy because of their immune regulatory functions and potent cytotoxic potential. In this study, we evaluated the cytotoxicity of combinations of chemotherapy and NKT cells to determine whether there is a potential to combine these treatment modalities for human cancer therapy. The cytotoxicity of NKT cells was tested against solid-tumor derived cell lines NCI-H358, DLD-1, HT-29, DU-145, TSU-Pr1 and MDA-MB231, with or without prior treatment of these target cells, with a range of chemotherapy agents. Low concentrations of chemotherapeutic agents led to sensitization of cell lines to NKT-mediated cytotoxicity, with the greatest effect being observed for prostate cancer cells. Synergistic cytotoxicity occurred in an NKT cell in a dose-dependent manner. Chemotherapy agents induced upregulation of cell surface TRAIL-R2 (DR5) and Fas (CD95) expression, increasing the capacity for NKT cells to recognize and kill via TRAIL- and FasL-mediated pathways. We conclude that administration of cytotoxic immune cells after chemotherapy may increase antitumor activities in comparison with the use of either treatment alone.
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As a key component of the ocular surface required for vision, the cornea has been extensively studied as a site for cell and tissue-based therapies. Historically, these treatments have consisted of donor corneal tissue transplants, but cultivated epithelial autografts have become established over the last 15 years as a routine treatment for ocular surface disease. Ultimately, these treatments are performed with the intention of restoring corneal transparency and a smooth ocular surface. The degree of success, however, is often dependent upon the inherent level of corneal inflammation at time of treatment. In this regard, the anti-inflammatory and immuno-modulatory properties of mesenchymal stromal cells (MSC) have drawn attention to these cells as potential therapeutic agents for corneal repair. The origins for MSC-based therapies are founded in part on observations of the recruitment of endogenous bone marrow-derived cells to injured corneas, however, an increasing quantity of data is emerging for MSC administered following their isolation and ex vivo expansion from a variety of tissues including bone marrow, adipose tissue, umbilical cord and dental pulp. In brief, evidence has emerged of cultured MSC, or their secreted products, having a positive impact on corneal wound healing and retention of corneal allografts in animal models. Optimal dosage, route of administration and timing of treatment, however, all remain active areas of investigation. Intriguingly, amidst these studies, have emerged reports of MSC transdifferentiation into corneal cells. Clearest evidence has been obtained with respect to expression of markers associated with the phenotype of corneal stromal cells. In contrast, the evidence for MSC conversion to corneal epithelial cell types remains inconclusive. In any case, the conversion of MSC into corneal cells seems unlikely to be an essential requirement for their clinical use. This field of research has recently become more complicated by reports of MSC-like properties for cultures established from the peripheral corneal stroma (limbal stroma). The relationship and relative value of corneal-MSC compared to traditional sources of MSC such as bone marrow are at present unclear. This chapter is divided into four main parts. After providing a concise overview of corneal structure and function, we will highlight the types of corneal diseases that are likely to benefit from the anti-inflammatory and immuno-modulatory properties of MSC. We will subsequently summarize the evidence supporting the case for MSC-based therapies in the treatment of corneal diseases. In the third section we will review the literature concerning the keratogenic potential of MSC. Finally, we will review the more recent literature indicating the presence of MSC-like cells derived from corneal tissue.