Medical Principles and Practice 

About: Medical Principles and Practice is an academic journal published by Karger Publishers. The journal publishes majorly in the area(s): Medicine & Population. It has an ISSN identifier of 1011-7571. It is also open access. Over the lifetime, 2352 publications have been published receiving 37929 citations.

Mechanisms of drug resistance in cancer chemotherapy.

Abstract: The management of cancer involves procedures, which include surgery, radiotherapy and chemotherapy Development of chemoresistance is a persistent problem during the treatment of local and disseminated disease A plethora of cytotoxic drugs that selectively, but not exclusively, target actively proliferating cells include such diverse groups as DNA alkylating agents, antimetabolites, intercalating agents and mitotic inhibitors Resistance constitutes a lack of response to drug-induced tumour growth inhibition; it may be inherent in a subpopulation of heterogeneous cancer cells or be acquired as a cellular response to drug exposure Resistance varies Although regulatory approval may require efficacy in as few as 20% of trial cohorts, a drug may subsequently be used in unselected patients displaying resistance to the treatment Principal mechanisms may include altered membrane transport involving the P-glycoprotein product of the multidrug resistance (MDR) gene as well as other associated proteins, altered target enzyme (eg mutated topoisomerase II), decreased drug activation, increased drug degradation due to altered expression of drug-metabolising enzymes, drug inactivation due to conjugation with increased glutathione, subcellular redistribution, drug interaction, enhanced DNA repair and failure to apoptose as a result of mutated cell cycle proteins such as p53 Attempts to overcome resistance mainly involve the use of combination drug therapy using different classes of drugs with minimally overlapping toxicities to allow maximal dosages and with narrowest cycle intervals, necessary for bone marrow recovery Adjuvant therapy with P-glycoprotein inhibitors and, in specific instances, the use of growth factor and protein kinase C inhibitors are newer experimental approaches that may also prove effective in abrogating or delaying onset of resistance Gene knockout using antisense molecules may be another effective way of blocking drug resistance genes Conversely, drug resistance may also be used to good purpose by transplanting retrovirally transformed CD34 cells expressing the MDR gene to protect the bone marrow during high-dose chemotherapy

Natural Products as a Vital Source for the Discovery of Cancer Chemotherapeutic and Chemopreventive Agents.

Abstract: Throughout history, natural products have played a dominant role in the treatment of human ailments. For example, the legendary discovery of penicillin transformed global existence. Presently, natural products comprise a large portion of current-day pharmaceutical agents, most notably in the area of cancer therapy. Examples include Taxol, vinblastine, and camptothecin. These structurally unique agents function by novel mechanisms of action; isolation from natural sources is the only plausible method that could have led to their discovery. In addition to terrestrial plants as sources for starting materials, the marine environment (e.g., ecteinascidin 743, halichondrin B, and dolastatins), microbes (e.g., bleomycin, doxorubicin, and staurosporin), and slime molds (e.g., epothilone B) have yielded remarkable cancer chemotherapeutic agents. Irrespective of these advances, cancer remains a leading cause of death worldwide. Undoubtedly, the prevention of human cancer is highly preferable to treatment. Cancer chemoprevention, the use of vaccines or pharmaceutical agents to inhibit, retard, or reverse the process of carcinogenesis, is another important approach for easing this formidable public health burden. Similar to cancer chemotherapeutic agents, natural products play an important role in this field. There are many examples, including dietary phytochemicals such as sulforaphane and phenethyl isothiocyanate (cruciferous vegetables) and resveratrol (grapes and grape products). Overall, natural product research is a powerful approach for discovering biologically active compounds with unique structures and mechanisms of action. Given the unfathomable diversity of nature, it is reasonable to suggest that chemical leads can be generated that are capable of interacting with most or possibly all therapeutic targets.

Problem-based learning and medical education forty years on. A review of its effects on knowledge and clinical performance.

Abstract: Problem-based learning (PBL) has swept the world of medical education since its introduction 40 years ago, leaving a trail of unanswered or partially answered questions about its benefits The literat

Evaluation of High-Sensitivity C-Reactive Protein and Serum Lipid Profile in Southeastern Nigerian Women with Pre-Eclampsia

Abstract: Objective: To evaluate the serum C-reactive protein (CRP) and lipid profile in women with pre-eclampsia. Materials and Methods:

Amyloid-Beta: A Crucial Factor in Alzheimer's Disease

Abstract: Alzheimer's disease (AD) is the most prevalent form of dementia which affects people older than 60 years of age. In AD, the dysregulation of the amyloid-beta (Aβ) level leads to the appearance of senile plaques which contain Aβ depositions. Aβ is a complex biological molecule which interacts with many types of receptors and/or forms insoluble assemblies and, eventually, its nonphysiological depositions alternate with the normal neuronal conditions. In this situation, AD signs appear and the patients experience marked cognitional disabilities. In general, intellect, social skills, personality, and memory are influenced by this disease and, in the long run, it leads to a reduction in quality of life and life expectancy. Due to the pivotal role of Aβ in the pathobiology of AD, a great deal of effort has been made to reveal its exact role in neuronal dysfunctions and to finding efficacious therapeutic strategies against its adverse neuronal outcomes. Hence, the determination of its different molecular assemblies and the mechanisms underlying its pathological effects are of interest. In the present paper, some of the well-established structural forms of Aβ, its interactions with various receptors and possible molecular and cellular mechanisms underlying its neurotoxicity are discussed. In addition, several Aβ-based rodent models of AD are reviewed.