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991.
Drug eruptions are among the most common adverse drug reactions, affecting approximately 3% of hospitalised patients. Although the rate of severe cutaneous adverse reactions to medications is low, these reactions can affect anyone who takes medication, and can result in death or disability. Two general patterns can be distinguished, depending on the type of onset of these cutaneous adverse drug reactions: acute or chronic. Acute-onset events are usually rather specific cutaneous 'syndromes' that constitute emergencies and should therefore be promptly recognised and treated, while chronic-onset events often present as dermatological diseases. The challenge is therefore to recognise the drug aetiology in front of a 'classical' dermatosis such as acne, lichen or pemphigus. Therefore, clinicians should carefully evaluate the signs or symptoms of all adverse reactions thought to be drug related, and discontinue the offending agent when feasible. Erythematous drug eruptions are the most frequent and less severe acute immune drug-induced rashes, and are sometimes difficult to differentiate from viral eruptions. On the other hand, acute urticaria and angioedema are sometimes life-threatening eruptions for which a drug aetiology must be investigated. Photosensitivity, vasculitis and skin necrosis belong to the acute onset reactions, which are not always drug-induced, in contrast to fixed drug eruptions. The early recognition of acute generalised exanthematous pustulosis, DRESS (drug reaction with eosinophilia and systemic symptoms) syndrome, Stevens-Johnson syndrome and toxic epidermal necrolysis are of high importance because of the specific mechanisms involved and the different prognosis of each of these diseases. Chronic onset drug-induced disorders include pigmentary changes, drug-induced autoimmune bullous diseases, lupus, pseudo lymphoma and acneiform eruptions; these are discussed, along with specific data on drug-induced hair and nail disorders. As the disorders are numerous, the mechanisms and the drugs involved in the development of these various reactions are multiple. The list of drugs discussed in relation to the different disorders are as accurate as possible at the time of preparation of this review, but will need updating as new drugs emerge onto the market. We emphasize the clinical recognition, pathophysiology and treatment of skin, hair and nail adverse drug reactions, and the role of each doctor involved in the management of these patients in the notification of the adverse drug reaction to health authorities, using the minimal requirement for notification proposed. 相似文献
992.
Abnormalities in the regulation of neurotransmitter release and/or abnormal levels of extracellular neurotransmitter concentrations have remained core components of hypotheses on the neuronal foundations of behavioral and cognitive disorders and the symptoms of neuropsychiatric and neurodegenerative disorders. Furthermore, therapeutic drugs for the treatment of these disorders have been developed and categorized largely on the basis of their effects on neurotransmitter release and resulting receptor stimulation. This perspective stresses the theoretical and practical implications of hypotheses that address the dynamic nature of neurotransmitter dysregulation, including the multiple feedback mechanisms regulating synaptic processes, phasic and tonic components of neurotransmission, compartmentalized release, differentiation between dysregulation of basal vs activated release, and abnormal release from neuronal systems recruited by behavioral and cognitive activity. Several examples illustrate that the nature of the neurotransmitter dysregulation in animal models, including the direction of drug effects on neurotransmitter release, depends fundamentally on the state of activity of the neurotransmitter system of interest and on the behavioral and cognitive functions recruiting these systems. Evidence from evolving techniques for the measurement of neurotransmitter release at high spatial and temporal resolution is likely to advance hypotheses describing the pivotal role of neurotransmitter dysfunction in the development of essential symptoms of major neuropsychiatric disorders, and also to refine neuropharmacological mechanisms to serve as targets for new treatment approaches. The significance and usefulness of hypotheses concerning the abnormal regulation of the release of extracellular concentrations of primary messengers depend on the effective integration of emerging concepts describing the dynamic, compartmentalized, and activity-dependent characteristics of dysregulated neurotransmitter systems. 相似文献
993.
Katleen Baert Bruno De Meulenaer Frederik Verdonck Inge Huybrechts Stefaan De Henauw Peter A Vanrolleghem Johan Debevere Frank Devlieghere 《Food and chemical toxicology》2007,45(9):1745-1751
The objective of the present study was to evaluate the patulin exposure of children consuming organic, handcrafted or conventional apple juice through a probabilistic approach and to evaluate the effectiveness of several risk management options aiming to reduce the risk for children due to patulin exposure. However, a large part of the data on patulin contamination of apple juice fell under the limit of detection (LOD). Different methods were tested to deal with these so-called left censored data and a uniform distribution with uncertain bounds was selected to handle this censorship. Variability and uncertainty assessment of patulin exposure showed that 0.9% [90% confidence interval (CI): 0.3-1.8%] of the children consuming only organic apple juice exceed the tolerable daily intake (TDI). For consumers of conventional and handcrafted apple juice this was respectively 0.1% [90% CI: 0-0.3%] and 0% [90% CI: 0-0.2%]. Reduction of the patulin contamination in apple juice to concentrations below 25 microg/kg reduced the percentage of the children exceeding the TDI to 0% [90%CI: 0-0.2%] for organic apple juice. Reduction of the apple juice consumption was less effective than a reduction of the patulin concentration in apple juice and is only useful when the patulin concentration of apple juice is below 25 microg/kg. 相似文献
994.
Forte WC Noyoya AM de Carvalho Júnior FF Bruno S 《Allergologia et immunopathologia》2000,28(6):328-331
A 21 years old male suffered from repeated furunculosis in different regions of the body over the last two years. This coincided with the start of professional activities in hospital surroundings. The purulent secretions all showed growth of Staphylococcus aureus. All laboratory tests were normal except for a decrease of the neutrophil phagocytic ingestion phase. Before the diagnosis of defective phagocytosis was made, antibiotic treatment was started about 4 to 5 days after the appearance of the infectious process and the furunculosis led to abscess formation with difficult healing and cellulitis. After the diagnosis of defective phagocytosis ingestion phase, personal hygiene was intensified during and after work shifts at the hospital and antibiotic treatment was started at the first signs of folliculitis, which showed healing. 相似文献
995.
Dr Fabio Mazza Claudia Stefanutti Serafina Di Giacomo Antonio Vivenzio Nadia Fraone Bruno Mazzarella Antonello Bucci 《Am J Cardiovasc Drugs》2008,8(4):265-270
BACKGROUND AND OBJECTIVE: Despite the favorable effects of reduction of low-density lipoprotein-cholesterol (LDL-C) levels in decreasing the risk of coronary heart disease, many patients treated with lipid-lowering HMG-CoA reductase inhibitors (statins) do not achieve goal LDL-C levels. This may be due to high doses of statins prescribed that could potentially induce adverse effects and compromise patient safety and compliance with considerable expense in the long-term. We compared the actions of rosuvastatin and atorvastatin, administered at the low dosages of 10 and 20 mg/day, respectively, in reducing plasma LDL-C levels and their effects on other components of the atherogenic lipid profile in patients with primary hypercholesterolemia. METHODS: In this randomized, parallel group, open-label clinical study, 106 patients with LDL-C >200 mg/dL were treated with rosuvastatin 10 mg/day (group A; n = 52), or atorvastatin 20 mg/day (group B; n = 54) for 48 weeks. RESULTS: At 48 weeks, rosuvastatin 10 mg/day was associated with a significantly greater reduction in plasma LDL-C levels compared with atorvastatin 20 mg/day (-44.32% vs -30%; p < 0.005). Compared with atorvastatin, rosuvastatin also produced a greater reduction in plasma total cholesterol, triglycerides, and non-high-density lipoprotein-cholesterol (non-HDL-C) levels (p < 0.005). Plasma HDL-C levels were not affected significantly, independent of the drug used. CONCLUSION: In high-risk patients with primary hypercholesterolemia, rosuvastatin 10 mg/day was more efficacious than atorvastatin 20 mg/day in reducing plasma LDL-C levels, enabling goal LDL-C levels to be achieved and improving other lipid parameters. Both treatments were well tolerated over 48 weeks. 相似文献
996.
997.
Sylvain Ladoire Laurent Arnould Lionel Apetoh Bruno Coudert Francois Martin Bruno Chauffert Pierre Fumoleau Fran?ois Ghiringhelli 《Clinical cancer research》2008,14(8):2413-2420
PURPOSE: T-cell infiltration is associated with good tumor prognosis in many cancers. To assess the capacity of neoadjuvant chemotherapy to affect T-cell infiltration in breast cancer, we evaluated CD3 and CD8 infiltrates, and the Foxp3 immunosuppressive T cells. EXPERIMENTAL DESIGN: CD3+, CD8+, and Foxp3+ cell infiltrates were detected by immunohistochemistry in a series of 56 breast cancer patients before and after the end of neoadjuvant chemotherapy. RESULTS: Poor prognostic factors (negative hormonal receptors, high tumor grade, and nodal involvement) were associated with a significantly higher number of CD3, CD8, and Foxp3 infiltrates before the beginning of chemotherapy. Chemotherapy resulted in a decrease in Foxp3 infiltrates, whereas the level of CD8 and CD3 infiltrates remained unchanged. Pathologic complete responses (pCR) had a drastic decrease of Foxp3+ cells, whereas these cells remained elevated in nonresponders. A cutoff criterion that combined high CD8 infiltration and no Foxp3 cell infiltration on surgical specimens is associated with pCR with a sensitivity of 75% and a specificity of 93%. The infiltrate of cytotoxic TiA1 and granzyme B-positive cells was dramatically enhanced after chemotherapy only in patients with pCR. By multivariate analysis, association of a high CD8 infiltration and no Foxp3 infiltration on final histologic specimens were independently associated with pCR. CONCLUSION: These findings indicate that pCR to neoadjuvant chemotherapy is associated with an immunologic profile combining the absence of immunosuppressive Foxp3 cells and the presence of a high number of CD8 T cells and cytotoxic cells. These results argue for the induction of an antitumor immune response by chemotherapy. 相似文献
998.
Rossella Libé Amato Fratticci Joel Coste Frédérique Tissier Anelia Horvath Bruno Ragazzon Fernande Rene-Corail Lionel Groussin Xavier Bertagna Marie Laure Raffin-Sanson Constantine A Stratakis Jérome Bertherat 《Clinical cancer research》2008,14(12):4016-4024
PURPOSE: We have reported previously nonsense inactivating mutations of the phosphodiesterase 11A (PDE11A) gene in patients with micronodular adrenocortical hyperplasia and Cushing syndrome. The aim of this study is to investigate the presence of somatic or germ-line PDE11A mutations in various types of adrenocortical tumors: ACTH-independent macronodular adrenocortical hyperplasia (AIMAH), adrenocortical adenoma (ACA), and adrenocortical cancer (ACC). EXPERIMENTAL DESIGN: PDE11A was sequenced in 117 adrenocortical tumors and 192 controls subjects; immunohistochemistry for PDE11A and tumor cyclic AMP levels were studied in a subgroup of adrenocortical tumors. RESULTS: One PDE11A inactivating mutation (R307X) was found in one ACA, 22 germ-line missense variants (18.8%) were found in adrenocortical tumors, and only 11 missense variants (5.7%) were found in controls. By comparing the common mutations, a higher frequency of mutations in adrenocortical tumors than in age/sex-matched controls were observed [16% versus 10% in ACC, 19% versus 10% in ACA, and 24% versus 9% in AIMAH; odds ratio (OR), 3.53; P = 0.05]. Somatic DNA from adrenocortical tumors with missense variants showed a wild-type allelic loss. A significant difference between ACC and controls was observed for a polymorphism in exon 6 (E421E; OR, 2.1; P = 0.03) and three associated polymorphisms located in intron 10-exon 11-intron 11 (OR, 0.5; P = 0.01). In AIMAH/ACA, cyclic AMP levels were higher than in normal adrenals and decreased PDE11A immunostaining was present in adrenocortical tumors with PDE11A variants. CONCLUSIONS: The present investigation of a large cohort of adrenocortical tumors suggests that PDE11A sequence defects predispose to a variety of lesions (beyond micronodular adrenocortical hyperplasia) and may contribute to the development of these tumors in the general population. 相似文献
999.
Slug (SNAI2) down-regulation by RNA interference facilitates apoptosis and inhibits invasive growth in neuroblastoma preclinical models 总被引:1,自引:0,他引:1
Roberta Vitali Camillo Mancini Vincenzo Cesi Barbara Tanno Mariateresa Mancuso Gianluca Bossi Ying Zhang Robert V Martinez Bruno Calabretta Carlo Dominici Giuseppe Raschellà 《Clinical cancer research》2008,14(14):4622-4630
PURPOSE: We assessed the relevance of Slug (SNAI2) for apoptosis resistance and invasion potential of neuroblastoma cells in vitro and in vivo. EXPERIMENTAL DESIGN: We evaluated the effect of imatinib mesylate on invasion and analyzed the genes modulated by imatinib mesylate treatment in neuroblastoma cells. Slug expression, inhibited by imatinib mesylate treatment, was knocked down in neuroblastoma cells by RNA interference, and the effects on invasion and apoptosis were evaluated in vitro. A pseudometastatic model of neuroblastoma in severe combined immunodeficient mice was used to assess the effects of Slug silencing alone or in combination with imatinib mesylate treatment on metastasis development. RESULTS: Microarray analysis revealed that several genes, including Slug, were down-regulated by imatinib mesylate. Slug expression was detectable in 8 of 10 human neuroblastoma cell lines. Two Slug-expressing cell lines were infected with a vector encoding a microRNA to Slug mRNA. Infected cells with reduced levels of Slug were tested for the expression of apoptosis-related genes (p53, Bax, and Bcl-2) identified previously as Slug targets. Bcl-2 was down-regulated in Slug-interfered cells. Slug down-regulation increased sensitivity to apoptosis induced by imatinib mesylate, etoposide, or doxorubicin. Invasion of Slug-silenced cells was reduced in vitro. Animals injected with Slug-silenced cells had fewer tumors than controls and the inhibition of tumor growth was even higher in animals treated with imatinib mesylate. CONCLUSIONS: Slug down-regulation facilitates apoptosis induced by proapoptotic drugs in neuroblastoma cells and decreases their invasion capability in vitro and in vivo. Slug inhibition, possibly combined with imatinib mesylate, may represent a novel strategy for treatment of metastatic neuroblastoma. 相似文献
1000.
Jean-Pierre Vannier Franoise Flamant Jacques Hemet Jean Michel Caillaud Max Gruner Bruno Bachy Ren Lefur Jean Lemerle Philippe Tron 《Pediatric blood & cancer》1991,19(3):187-191
Two cases of pancreatoblastoma in children are reported here. Only biopsies were made at laparotomy as surgical resection by duodeno-pancreatectomy was not possible. In both children a dramatic response was observed with chemotherapy: doxorubicin plus cisplatin for one, cyclophosphamide, actinomycin D, bleomycin, vinblastin sulfate, and cisplatin for the other. After completion of the chemotherapy the first patient had a local resection; then he had radiotherapy. He is alive in first remission 40 months after the end of the treatment. In the second patient, regional recurrence occurred 8 months after chemotherapy was ended. A transient second remission was obtained with ifosfamide plus etoposide alternating with epirubicin plus vincristine. The patient died 36 months after the diagnosis. Therefore, these two cases suggest that chemo therapy may be proposed before any attempt at surgical excision. Nevertheless, early consolidation by radical resection or irradiation must be considered. 相似文献