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Effective Therapeutic Agents (effective + therapeutic_agent)
Selected AbstractsRegulation of erythropoietin productionEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2005K.-U. Eckardt Abstract The glycoprotein hormone erythropoietin (EPO) is an essential growth and survival factor for erythroid progenitor cells, and the rate of red blood cell production is normally determined by the serum EPO concentration. EPO production is inversely related to oxygen availability, so that an effective feedback loop is established, which controls erythropoiesis. Since recombinant EPO became available as an effective therapeutic agent, significant progress has also been made in understanding the basis of this feedback control. The main determinant of EPO synthesis is the transcriptional activity of its gene in liver and kidneys, which is related to local oxygen tensions. This control is achieved by hypoxia-inducible transcription factors (HIF), consisting of a constitutive ,-subunit and one of two alternative oxygen-regulated HIF, subunits (HIF-1, and HIF-2,). In the presence of oxygen (normoxia) the HIF, subunits are hydroxylated, which targets them for proteasomal degradation. Under hypoxia, because of the lack of molecular oxygen, HIF cannot be hydroxylated and is thereby stabilized. Although HIF-1, was the first transcription factor identified through its ability to bind to an enhancer sequence of the EPO gene, more recent evidence suggests that HIF-2, is responsible for the regulation of EPO. Although EPO is a prime example for an oxygen- regulated gene, the role of the HIF system goes far beyond the regulation of EPO, because it operates widely in almost all cells and controls a broad transcriptional response to hypoxia, including genes involved in cell metabolism, angiogenesis and vascular tone. Further evidence suggests that apart from its effect as an erythropoietic hormone EPO acts as a paracrine, tissue-protective protein in the brain and possibly also in other organs. [source] Salt-resistant homodimeric bactenecin, a cathelicidin-derived antimicrobial peptideFEBS JOURNAL, Issue 15 2008Ju Y. Lee The cathelicidin antimicrobial peptide bactenecin is a ,-hairpin molecule with a single disulfide bond and broad antimicrobial activity. The proform of bactenecin exists as a dimer, however, and it has been proposed that bactenecin is released as a dimer in vivo, although there has been little study of the dimeric form of bactenecin. To investigate the effect of bactenecin dimerization on its biological activity, we characterized the dimer's effect on phospholipid membranes, the kinetics of its bactericidal activity, and its salt sensitivity. We initially synthesized two bactenecin dimers (antiparallel and parallel) and two monomers (,-hairpin and linear). Under oxidative folding conditions, reduced linear bactenecin preferentially folded into a dimer forming a ladder-like structure via intermolecular disulfide bonding. As compared to the monomer, the dimer had a greater ability to induce lysis of lipid bilayers and was more rapidly bactericidal. Interestingly, the dimer retained antimicrobial activity at physiological salt concentrations (150 mm NaCl), although the monomer was inactivated. This salt resistance was also seen with bactenecin dimer containing one intermolecular disulfide bond, and the bactenecin dimer appears to undergo multimeric oligomerization at high salt concentrations. Overall, dimeric bactenecin shows potent and rapid antimicrobial activity, and resists salt-induced inactivation under physiological conditions through condensation and oligomerization. These characteristics shed light on the features that a peptide would need to serve as an effective therapeutic agent. [source] Short-term efficacy of tacrolimus ointment and impact on quality of lifePEDIATRICS INTERNATIONAL, Issue 3 2009Yasuto Kondo Abstract Background:, Topical calcineurin inhibitor (TCI) was reported to be an effective therapeutic agent for patients with atopic dermatitis (AD), for not only improving clinical findings but also for reducing pruritus. Recently in Japan tacrolimus ointment (0.03%) as a TCI was approved for use in children aged ,2 years. There have been no reports, however, on the impact of TCI on quality of life (QOL) in pediatric AD in Japan. The purpose of the present study was therefore to evaluate the efficacy of tacrolimus ointment (0.03%) in the short-term and the impact on patient QOL. Methods:, A total of 30 pediatric patients with AD, whose skin problems were not sufficiently controlled by mid-high potency topical glucocorticosteroids, were enrolled. Efficacy was assessed on score of cutaneous findings, pruritus, sleeping disorder, and QOL. Results:, Three patients discontinued because of skin burning (n = 1), generalized herpes infection (n = 1), and feeling of lack of efficacy (n = 1), leaving a final total of 27 patients who were evaluated. Significant improvements in clinical findings, pruritus, and sleeplessness were observed within 1 week of treatment and consequently each QOL category was also improved. These improvements continued for the duration of the study. Conclusions:, Tacrolimus ointment therapy is rapidly effective for not only clinical symptoms (cutaneous findings, pruritus and sleeplessness) but also in QOL of AD pediatric patients aged 2 years. [source] Brachioradial pruritus successfully treated with gabapentinTHE JOURNAL OF DERMATOLOGY, Issue 7 2010Sadik YILMAZ Abstract Brachioradial pruritus (BRP) is a mysterious entity characterized by localized pruritus of the dorsolateral aspect of the arm. The precise etiology of BRP remains unknown, but sun exposure and/or cervical spine lesions seem to be triggering or at least aggravating factors. Many treatment alternatives including non-steroidal anti-inflammatory drugs, topical capsaicin, topical corticosteroids, photoprotection, carbamazepine and acupuncture have been used with different success rates. Recently, gabapentin, an antiepileptic agent, has been reported to be an effective therapeutic agent in BRP. Herein, we report a 64-year-old man with BRP who showed good response to gabapentin therapy. [source] Abrogation of antibody-induced arthritis in mice by a self-activating viridin prodrug and association with impaired neutrophil and endothelial cell functionARTHRITIS & RHEUMATISM, Issue 8 2009Lars Stangenberg Objective To test a novel self-activating viridin (SAV) prodrug that slowly releases wortmannin, a potent phosphoinositide 3-kinase inhibitor, in a model of antibody-mediated inflammatory arthritis. Methods The SAV prodrug was administered to K/BxN mice or to C57BL/6 (B6) mice that had been injected with K/BxN serum. Ankle thickness was measured, and histologic changes were scored after a 10-day disease course (serum-transfer arthritis). Protease activity was measured by a near-infrared imaging approach using a cleavable cathepsin,selective probe. Further near-infrared imaging techniques were used to analyze early changes in vascular permeability after serum injection, as well as neutrophil,endothelial cell interactions. Neutrophil functions were assessed using an oxidative burst assay as well as a degranulation assay. Results SAV prevented ankle swelling in mice with serum-transfer arthritis in a dose-dependent manner. It also markedly reduced the extent of other features of arthritis, such as protease activity and histology scores for inflammation and joint erosion. Moreover, SAV was an effective therapeutic agent. The underlying mechanisms for the antiinflammatory activity were manifold. Endothelial permeability after serum injection was reduced, as was firm neutrophil attachment to endothelial cells. Endothelial cell activation by tumor necrosis factor , was impeded by SAV, as measured by the expression of vascular cell adhesion molecule. Crucial neutrophil functions, such as generation of reactive oxygen species and degranulation of protease-laden vesicles, were decreased by SAV administration. Conclusion A novel SAV prodrug proved strongly antiinflammatory in a murine model of antibody-induced inflammatory arthritis. Its activity could be attributed, at least in part, to the inhibition of neutrophil and endothelial cell functions. [source] Migraine Education Improves Quality of Life in a Primary Care SettingHEADACHE, Issue 4 2010Timothy R. Smith MD (Headache 2010;50:600-612) Objective., The objective of this study was to evaluate the effectiveness of the Mercy Migraine Management Program (MMMP), an educational program for physicians and patients. The primary outcome was change in headache days from baseline at 3, 6, and 12 months. Secondary outcomes were changes in migraine-related disability and quality of life, worry about headaches, self-efficacy for managing migraines, emergency room (ER) visits for headache, and satisfaction with headache care. Background., Despite progress in the understanding of the pathophysiology of migraine and development of effective therapeutic agents, many practitioners and patients continue to lack the knowledge and skills to effectively manage migraine. Educational efforts have been helpful in improving the quality of care and quality of life for migraine sufferers. However, little work has been performed to evaluate these changes over a longer period of time. Also, there is a paucity of published research evaluating the influence of education about migraine management on cognitive and emotional factors (for example, self-efficacy for managing headaches, worry about headaches). Methods., In this open-label, prospective study, 284 individuals with migraine (92% female, mean age = 41.6) participated in the MMMP, an educational and skills-based program. Of the 284 who participated in the program, 228 (80%) provided data about their headache frequency, headache-related disability (as measured by the Headache Impact Test-6 (HIT-6), migraine-specific quality of life (MSQ), worry about headaches, self-efficacy for managing headaches, ER visits for headaches, and satisfaction with care at 4 time points over 12 months (baseline, 3 months, 6 months, 12 months). Results., Overall, 46% (106) of subjects reported a 50% or greater reduction in headache frequency. Over 12 months, patients reported fewer headaches and improvement on the HIT-6 and MSQ (all P < .001). The improvement in headache impact and quality of life was greater among those who had more worry about their headaches at baseline. There were also significant improvements in "worry about headaches,""self-efficacy for managing headaches," and "satisfaction with headache care." Conclusion., The findings demonstrate that patients participating in the MMMP reported improvements in their headache frequency as well as the cognitive and emotional aspects of headache management. This program was especially helpful among those with high amounts of worry about their headaches at the beginning of the program. The findings from this study are impetus for further research that will more clearly evaluate the effects of education and skill development on headache characteristics and the emotional and cognitive factors that influence headache. [source] Fractures and avascular necrosis before and after orthotopic liver transplantation: Long-term follow-up and predictive factors,HEPATOLOGY, Issue 4 2007Maureen M. J. Guichelaar With early posttransplant bone loss, orthotopic liver transplantation (OLT) recipients experience a high rate of fracturing and some avascular necrosis (AVN), but little is known about the incidence of and predictive factors for these skeletal complications. We studied 360 consecutive patients who underwent transplantation for primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) and assessed both vertebral and nonvertebral (rib, pelvic, and femur) fractures in a protocolized fashion. Before OLT, 20% of the patients had experienced fracturing, and 1.4% of the patients had experienced AVN. Following OLT, there was a sharp increase in fracturing, with a 30% cumulative incidence of fractures at 1 year and 46% at 8 years after transplantation. In contrast to previous studies, there was a similar incidence of posttransplant vertebral and nonvertebral fractures. The greatest risk factors for posttransplant fracturing were pretransplant fracturing and the severity of osteopenia and posttransplant glucocorticoids. Nine percent of the liver recipients experienced AVN after OLT, and this correlated with pretransplant and posttransplant lipid metabolism, bone disease (bone mineral density and fracturing), and posttransplant glucocorticoids. A novel association between cholestasis and AVN was also identified, the mechanism for which is not known. Conclusion: Fortunately, recent years have seen an increase in the bone mass of liver recipients and, along with this, less fracturing and less AVN. Nonetheless, 25% of patients undergoing OLT for chronic cholestatic liver disease still develop de novo fractures after OLT; this situation demands an ongoing search for effective therapeutic agents for these patients. (HEPATOLOGY 2007.) [source] Angiogenesis in the female reproductive organs: pathological implicationsINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2002Lawrence P. Reynolds Summary. The female reproductive organs (ovary, uterus, and placenta) are some of the few adult tissues that exhibit regular intervals of rapid growth. They also are highly vascular and have high rates of blood flow. Angiogenesis, or vascular growth, is therefore an important component of the growth and function of these tissues. As with many other tissues, vascular endothelial growth factors (VEGFs) and fibroblast growth factors (FGFs) appear to be major angiogenic factors in the female reproductive organs. A variety of pathologies of the female reproductive organs are associated with disturbances of the angiogenic process, including dysfunctional uterine bleeding, endometrial hyperplasia and carcinoma, endometriosis, failed implantation and subnormal foetal growth, myometrial fibroids (uterine leiomyomas) and adenomyosis, ovarian hyperstimulation syndrome, ovarian carcinoma, and polycystic ovary syndrome. These pathologies are also associated with altered expression of VEGFs and/or FGFs. In the near future, angiogenic or antiangiogenic compounds may prove to be effective therapeutic agents for treating these pathologies. In addition, monitoring of angiogenesis or angiogenic factor expression may provide a means of assessing the efficacy of these therapies. [source] Prostaglandin E2 and its cognate EP receptors control human adult articular cartilage homeostasis and are linked to the pathophysiology of osteoarthritisARTHRITIS & RHEUMATISM, Issue 2 2009Xin Li Objective To elucidate the pathophysiologic links between prostaglandin E2 (PGE2) and osteoarthritis (OA) by characterizing the catabolic effects of PGE2 and its unique receptors in human adult articular chondrocytes. Methods Human adult articular chondrocytes were cultured in monolayer or alginate beads with and without PGE2 and/or agonists of EP receptors, antagonists of EP receptors, and cytokines. Cell survival, proliferation, and total proteoglycan synthesis and accumulation were measured in alginate beads. Chondrocyte-related gene expression and phosphatidylinositol 3-kinase/Akt signaling were assessed by real-time reverse transcription,polymerase chain reaction and Western blotting, respectively, using a monolayer cell culture model. Results Stimulation of human articular chondrocytes with PGE2 through the EP2 receptor suppressed proteoglycan accumulation and synthesis, suppressed aggrecan gene expression, did not appreciably affect expression of matrix-degrading enzymes, and decreased the type II collagen:type I collagen ratio. EP2 and EP4 receptors were expressed at higher levels in knee cartilage than in ankle cartilage and in a grade-dependent manner. PGE2 titration combined with interleukin-1 (IL-1) synergistically accelerated expression of pain-associated molecules such as inducible nitric oxide synthase and IL-6. Finally, stimulation with exogenous PGE2 or an EP2 receptor,specific agonist inhibited activation of Akt that was induced by insulin-like growth factor 1. Conclusion PGE2 exerts an antianabolic effect on human adult articular cartilage in vitro, and EP2 and EP4 receptor antagonists may represent effective therapeutic agents for the treatment of OA. [source] Monoclonal antibodies as effective therapeutic agents for solid tumorsCANCER SCIENCE, Issue 8 2004Yuji Hinoda Monoclonal antibodies (mAbs) against growth factors or their receptors have been revealed to be effective therapeutic agents for solid tumors. Trastuzumab (humanized anti-HER2 mAb) is the first mAb approved for the treatment of a solid tumor, metastatic breast cancer. Large-scale phase III clinical trials are now ongoing to further evaluate the additive effects on chemotherapy and the efficacy as a maintenance monotherapy. Another anti-HER2 mAb CH401 that we developed also seems to have good potential. This chimeric mAb completely suppressed the growth of established human tumor xenografts in SCID mice after a single injection. Furthermore, CH401 characteristically showed much stronger induction of apoptosis in HER2-overexpressing gastric cancer cells compared to trastuzumab. Additional targets now being intensively evaluated are epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF). Both cetuximab (chimeric anti-EGFR mAb) and bevacizumab (humanized anti-VEGF mAb) have recently been shown to be of clinical value for metastatic colorectal cancer. Anti-idiotype mAbs are unique as active immunotherapeutic agents, and survival benefits have been observed in clinical trials for solid tumors. [source] | ||||||||||