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Many Substances (many + substance)
Selected AbstractsA11. UV-related skin hazards: allergic photodermatitisJOURNAL OF COSMETIC DERMATOLOGY, Issue 2 2002Paolo Pigatto Cases of dermatitis induced by exposure to ultra-violet radiation are increasingly encountered in clinical practice, with contact allergic photodermatitis accounting for about 10% of cases. Its frequency seems to be increasing, not only as a result of the increased use of cosmetic products and contact with some of the materials of working processes, but above all because of the greater exposure to both natural and artificial sources of UV radiation. Many substances have been defined ,photo-allergising' but their exact prevalence has varied over the years with the introduction and use of new substances in cosmetics and pharmaceutical products. For these, and other reasons, there are few studies concerning the prevalence and incidence of contact allergic photodermatitis in Italy. A total of 2160 patients with clinical histories suggestive of photoallergic contact dermatitis were seen. All patients underwent photopatch tests with haptens proposed by the Gruppo Italiano Ricerca Dermatiti da Contatto plus other substances suggested by each patient's history. 518 patients (24%) were positive to at least one test substance of the standard series or to added substances. Typical photoallergic reactions were seen in 423 subjects, representing 19.5% of the total population. Topical drugs are the substances most frequently involved in photodermatitis. The incidence in our population was about equal for antimicrobial agents, additives to fragrances, and fragrances themselves. Other allergens frequently found were sun screening agents which were the second group of haptens with clear-cut relevance. [source] Epidemiologic evaluation of pharmaceuticals with limited evidence of carcinogenicityINTERNATIONAL JOURNAL OF CANCER, Issue 9 2009Gary D. Friedman Abstract Thorough review by the International Agency for Research on Cancer (IARC) has resulted in classifying many substances, including pharmaceuticals, as probably or possibly carcinogenic to humans, based on experiments on animals or limited data on humans. We evaluated 9 such pharmaceuticals for evidence of carcinogenicity in patients receiving them in a large medical care program with automated pharmacy records and a cancer registry. Nested case,control analyses were performed in a cohort of 6.5 million subscribers with up to 12 years of follow-up, focusing on cancer sites suggested by previous evidence and other sites with odds ratio of at least 1.50, p < 0.01 and some evidence of dose,response. Unmeasured confounding was estimated in sensitivity analyses. We found some supportive evidence for carcinogenicity of griseofulvin, metronidazole and phenytoin and for the known carcinogen, cyclophosphamide, which was added for validation of our data and analyses. Findings for chloramphenicol, iron-dextran complex, phenoxybenzamine and phenobarbital were essentially non-contributory. Confounding by cigarette smoking and prior thyroid disease could account, respectively, for associations of oxazepam with lung cancer and propylthiouracil with thyroid cancer. Although not definitive, these findings should be considered in the evaluations of these pharmaceuticals. © 2009 UICC [source] Sarcolemmal and mitochondrial KATP channels and myocardial ischemic preconditioningJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2002J. N. Peart Abstract Ischemic preconditioning (IPC) is the phenomenon whereby brief periods of ischemia have been shown to protect the myocardium against a sustained ischemic insult. The result of IPC may be manifest as a marked reduction in infarct size, myocardial stunning, or incidence of arrhythmias. While many substances and pathways have been proposed to play a role in the signal transduction mediating the cardioprotective effect of IPC, overwhelming evidence indicates an intimate involvement of the ATP-sensitive potassium channel (KATP channel) in this process. Initial hypotheses suggested that the surface or sarcolemmal KATP (sarcKATP) channel mediated the cardioprotective effects of IPC. However, much research has subsequently supported a major role for the mitochondrial KATP channel (mitoKATP) as the one involved in IPC-mediated cardioprotection. This review presents evidence to support a role for the sarcKATP or the mitoKATP channel as either triggers and/or downstream mediators in the phenomenon of IPC. [source] Return of the cycad hypothesis , does the amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC) of Guam have new implications for global health?NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2005P. G. Ince Recently published work provides evidence in support of the cycad hypothesis for Lytico,Bodig, the Guamanian amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC), based on a new understanding of Chamorro food practices, a cyanobacterial origin of ,-methylaminoalanine (BMAA) in cycad tissue, and a possible mechanism of biomagnification of this neurotoxic amino acid in the food chain. BMAA is one of two cycad chemicals with known neurotoxic properties (the other is cycasin, a proven developmental neurotoxin) among the many substances that exist in these highly poisonous plants, the seeds of which are used by Chamorros for food and medicine. The traditional diet includes the fruit bat, a species that feeds on cycad seed components and reportedly bioaccumulates BMAA. Plant and animal proteins provide a previously unrecognized reservoir for the slow release of this toxin. BMAA is reported in the brain tissue of Guam patients and early data suggest that some Northern American patients dying of Alzheimer's disease (AD) have detectable brain levels of BMAA. The possible role of cyanobacterial toxicity in sporadic neurodegenerative disease is therefore worthy of consideration. Recent neuropathology studies of ALS/PDC confirm understanding of this disorder as a ,tangle' disease, based on variable anatomical burden, and showing biochemical characteristics of ,AD-like' combined 3R and 4R tau species. This model mirrors the emerging view that other neurodegenerative disease spectra comprise clusters of related syndromes, owing to common molecular pathology, with variable anatomical distribution in the nervous system giving rise to different clinical phenotypes. Evidence for ,ubiquitin-only' inclusions in ALS/PDC is weak. Similarly, although there is evidence for ,-synucleinopathy in ALS/PDC, the parkinsonian component of the disease is not caused by Lewy body disease. The spectrum of sporadic AD includes involvement of the substantia nigra and a high prevalence of ,incidental',-synucleinopathy in sporadic AD is reported. Therefore the pathogenesis of Lytico,Bodig appears still to have most pertinence to the ongoing investigation of the pathogenesis of AD and other tauopathies. [source] US4 Pharmacotherapy complicating dental surgeryORAL DISEASES, Issue 2006Boras Planning dental treatments for patients taking antithrombotic can be difficult for the general dental practitioner, particularly when surgical interventions are needed. The drugs employed in the long-term treatment of such patients include platelet aggregation inhibitors and oral anticoagulants. Platelet aggregation inhibitors do not represent a contraindication to oral surgery. The activity of oral anticoagulants can be affected by many substances, for this reason it is necessary to monitor by INR the patients taking those drugs. When INR is within therapeutic limits for the more common conditions, most of the oral surgery interventions do not need any special precaution. Evidence indicates that suspending antithrombotic drugs is not indicate, as complications following a thrombotic accident are more frequent and serious than bleedings following oral surgery. It is well known that systemic corticosteroid therapy due to the effect on adrenal suppression can interfere with dental surgical procedures. However, that is largely dependent on the type and dose of corticosteroid that patient is currently taking, or has been taking in the last 12 months and on the type and extent of surgical procedure which is to be performed. Surgical management of dental patients with history of systemic corticosteroid therapy is proposed from the existing literature. [source] Glutathione S-transferases in the adaptation to plant secondary metabolites in the Myzus persicae aphidARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 3 2005Frédéric Francis Abstract Glutathione S-transferases (GST) in insects play an important role in the detoxification of many substances including allelochemicals from plants. Induction of GST activity in Myzus persicae in response to secondary metabolites from Brassica plants was determined using different host plant species and confirmed using artificial diet with pure allelochemicals added. The 2,4-dinitro-1-iodobenzene (DNIB) was found to be a useful substrate for identifying particular GSTs in insects. GSTs from M. persicae were purified using different affinity chromatography columns and related kinetic parameters were calculated. GST isoenzymes were characterised using electrophoretic methods. Although SDS-PAGE results indicated similarity among the purified enzymes from each affinity column, biochemical studies indicated significant differences in kinetic parameters. Finally, the GST pattern of M. persicae was discussed in terms of insect adaptation to the presence of plant secondary substances such as the glucosinolates and the isothiocyanates, from Brassicaceae host plants. Arch. Insect Biochem. Physiol. 58:166,174, 2005. © 2005 Wiley-Liss, Inc. [source] The construction of web database server-client system for functional food factorsBIOFACTORS, Issue 1-4 2004Xing-Gang Zhuo Abstract In food, other than known nutrients, such as lipid, carbohydrate, protein, vitamins, and minerals, many substances with physiological function and medicinal action exist, and it is contributing to healthy improvement and/or prevention of illness. Although carotenoid, flavonoid and polyphenol, terpenoid, volatile substance and sulfur compounds, peptide, etc. have the function of illness prevention, and research of those non-nutrient functional food factors (FFF) became globally active, the research of this field is not yet done systematically. We evaluate function of FFF and reappraise known knowledge, and this knowledge is standardized and accumulated, aimed at building a web database server-client system which is easy to use for the people and nutritional research. We also collected related data such as chemical characters of FFF from literatures and other source, and formatted them into the database. We constructed the web database server-client system with MySQL database server and Apache web server based on Linux, and used Tomcat JSP engine for data connecting since they were reliable in stability and speed. We are opening the database at http://www.life-science.jp/FFF for test now. [source] | ||||||||||