NMR analysis of the iron ligand ethylenediaminedi(o-hydroxyphenyl)acetic acid (EDDHA) employed in fertilizers

The exceptional efficiency of the iron chelate of ethylenediaminedi(o-hydroxyphenyl)acetic acid (o,o-EDDHA) in correcting iron chlorosis in plants and the medical applications of various metallic chelates of this compound have long been recognized. As commercial preparations of o,o-EDDHA usually contain impurities, a method for their detection is proposed. By using one- and two-dimensional nuclear magnetic resonance two impurities were identified. The structure of one of these compounds was assigned to an isomer of EDDHA containing at least one p-hydroxyphenyl moiety. The structure of the other impurity was tentatively assigned to a byproduct of the EDDHA synthesis: 2,6-di[CH(COOH)NHCH(2)CH(2)NHCH(COOH)Ar]phenol (Ar = hydroxyphenyl). Both compounds were also detected in the EDDHA extracted from a commercial iron fertilizer.

Topographic classification, clinical characteristics, and diagnostic delay of cancer of the larynx/hypopharynx in Torino, Italy

The case series of a population-based case-control study of laryngeal and hypopharyngeal cancers in Torino, Italy, included 281 men with clinical and anamnestic data. Two hundred fifteen, 28, and 38 cancers originated from the endolarynx, epilarynx, and hypopharynx, respectively. Regions invaded by the tumor were divided into 26 subsites. A classification based on the number of invaded subsites was proposed, which agreed well with the T classification of the TNM system. Cancers originating from the hypopharynx invaded more subsites than cancers from the endolarynx, and among the latter, supraglottic were more invasive than glottic lesions. The number of invaded subsites was strongly associated with nodal involvement. Among symptoms at onset of disease and at diagnosis, patients with endolaryngeal lesions reported dysphonia and dyspnea more frequently, and patients with lesions from other regions had a higher prevalence of dysphagia, odynophagia, otalgia, and adenopathia. Clinical and epidemiologic results of this study suggest considering the endolarynx, epilarynx, and hypopharynx as separate anatomic entities. Diagnostic delay was not associated with tumor size and showed a negative trend with involvement of cervical lymph nodes, suggesting that stage at diagnosis is due to intrinsic differences in tumor aggressiveness.