Where does it hurt? Pain localization in osteoarthritis of the knee.
(9/3910)
OBJECTIVE: To identify the most common sites of pain in symptomatic knee osteoarthritis (OA) and to investigate clinical, radiographic and psychosocial associations of pain occurring in different locations. DESIGN: Sixty-eight outpatients with knee OA were interviewed in detail about their knee pain. Location of pain was recorded on a standard drawing of the knee. Validated instruments were used to measure pain severity, function, depression, anxiety, quality of life, fatigue, helplessness, self efficacy. Pain threshold was measured by dolorimetry and a knee examination performed. Radiographs (anterioposterior and lateral) were viewed if available. RESULTS: Most (85.3%) patients reported either 'generalized' (N = 35, 51.5%) or 'medial' (N = 23, 33.8%) knee pain. There were no differences between groups in pain severity, demographic or psychosocial variables, pain threshold or radiographic location or severity. However, function was significantly worse in the 'generalized' group (WOMAC function score 48.9 +/- 20.8 vs 34.2 +/- 22.3; P = 0.01): this remained significant after adjustment for potential confounding factors. The difference in function was most marked for activities involving knee bending. Early morning stiffness was also greater in the generalized group. CONCLUSIONS: Knee pain is not the same in all individuals with knee OA, confirming the heterogeneity of the condition. Location of pain is usually either generalized or medial. Patients with these patterns do not differ in demographic, radiographic or psychosocial variables but important differences in functional ability can be detected, suggesting differences in the underlying causes of pain and disability between the two groups. (+info)
The critical evaluation of a comprehensive mass spectral library.
(10/3910)
A description of the methods used to build a high quality, comprehensive reference library of electron-ionization mass spectra is presented. Emphasis is placed on the most challenging part of this project--the improvement of quality by expert evaluation. The methods employed for this task were developed over the course of a spectrum-by-spectrum review of a library containing well over 100,000 spectra. Although the effectiveness of this quality improvement task depended critically on the expertise of the evaluators, a number of guidelines are discussed which were found to be effective in performing this onerous and often subjective task. A number of specific examples of the particularly challenging task of spectrum editing are given. (+info)
A nomenclature system for labeling cyclic peptide fragments.
(11/3910)
A nomenclature system for labeling fragment ions of cyclic peptides is proposed. A fragment ion is labeled with a four-part descriptor for the general formula xnJZ, where x is the designation for the ion (e.g., lower case a or b, as are used for peptide fragments) and n is the number of amino acid residues in the ion. A b ion is the usual acylium ion or isomeric equivalent consisting of n amino-acid residues, and this ion may lose carbon monoxide to form an a ion. The subscripts J and Z are the one-letter (upper-case) codes for the two amino-acid residues connecting the backbone amide or ester bond, J-Z, that can be viewed as broken to form the decomposing linear ion. The symbol J is for the N-terminal amino-acid residue, and Z is that for the C-terminal amino-acid residue that result from the bond cleavage. The nomenclature system is applicable to a wide range of cyclic peptides, including depsipeptides, cyclic peptides containing modified or unusual amino acids, cyclic peptides bearing a linear peptide moiety, and cyclic peptides that are introduced into the gas phase as metal-ion cationized species. (+info)
Dense populations of a giant sulfur bacterium in Namibian shelf sediments.
(12/3910)
A previously unknown giant sulfur bacterium is abundant in sediments underlying the oxygen minimum zone of the Benguela Current upwelling system. The bacterium has a spherical cell that exceeds by up to 100-fold the biovolume of the largest known prokaryotes. On the basis of 16S ribosomal DNA sequence data, these bacteria are closely related to the marine filamentous sulfur bacteria Thioploca, abundant in the upwelling area off Chile and Peru. Similar to Thioploca, the giant bacteria oxidize sulfide with nitrate that is accumulated to +info)
The American College of Rheumatology nomenclature and case definitions for neuropsychiatric lupus syndromes.
(13/3910)
OBJECTIVE: To develop a standardized nomenclature system for the neuropsychiatric syndromes of systemic lupus erythematosus (NPSLE). METHODS: An international, multidisciplinary committee representing rheumatology, neurology, psychiatry, neuropsychology, and hematology developed case definitions, reporting standards, and diagnostic testing recommendations. Before and after the meeting, clinician committee members assigned diagnoses to sets of vignettes randomly generated from a pool of 108 NPSLE patients. To assess whether the nomenclature system improved diagnostic agreement, a consensus index was developed and pre- and postmeeting scores were compared by t-tests. RESULTS: Case definitions including diagnostic criteria, important exclusions, and methods of ascertainment were developed for 19 NPSLE syndromes. Recommendations for standard reporting requirements, minimum laboratory evaluation, and imaging techniques were formulated. A short neuropsychological test battery for the diagnosis of cognitive deficits was proposed. In the postmeeting exercise, a statistically significant improvement in diagnostic agreement was observed. CONCLUSION: The American College of Rheumatology (ACR) Nomenclature for NPSLE provides case definitions for 19 neuropsychiatric syndromes seen in SLE, with reporting standards and recommendations for laboratory and imaging tests. It is intended to facilitate and enhance clinical research, particularly multicenter studies, and reporting. In clinical settings, consultation with other specialists may be required. It should be useful for didactic purposes but should not be used uncritically or as a substitute for a clinical diagnosis. The complete case definitions are available on the ACR World Wide Web site: http://www.rheumatology .org/ar/ar.html. (+info)
Australopithecus garhi: a new species of early hominid from Ethiopia.
(14/3910)
The lack of an adequate hominid fossil record in eastern Africa between 2 and 3 million years ago (Ma) has hampered investigations of early hominid phylogeny. Discovery of 2.5 Ma hominid cranial and dental remains from the Hata beds of Ethiopia's Middle Awash allows recognition of a new species of Australopithecus. This species is descended from Australopithecus afarensis and is a candidate ancestor for early Homo. Contemporary postcranial remains feature a derived humanlike humeral/femoral ratio and an apelike upper arm-to-lower arm ratio. (+info)
When is a heterophile antibody not a heterophile antibody? When it is an antibody against a specific immunogen.
(15/3910)
Heterophile antibodies are antibodies produced against poorly defined antigens. These are generally weak antibodies with multispecific activities. Human anti-animal antibodies that develop as a result of treatments with animal immunoglobulins are antibodies with strong avidities, produced against well-defined antigens. Although heterophile antibodies and human anti-animal antibodies interfere with immunological assays by similar mechanisms, modes for identifying the sources of the antibodies and for circumventing or retarding the interference may differ. Unfortunately, there has not been a well-organized attempt to encourage correct definition of these antibodies. This problem of inexact definition is highlighted by recent articles in this Journal. In the present discussion, we examine the history leading to this problem and discuss the origins and the reasons that the nature of the antibody is important for rectifying the problem. We propose a simple nomenclature for general usage that should appropriately characterize these antibodies in most cases. (+info)
Environmental occurrence, analysis, and toxicology of toxaphene compounds.
(16/3910)
Toxaphene production, in quantities similar to those of polychlorinated biphenyls, has resulted in high toxaphene levels in fish from the Great Lakes and in Arctic marine mammals (up to 10 and 16 microg g-1 lipid). Because of the large variabiliity in total toxaphene data, few reliable conclusions can be drawn about trends or geographic differences in toxaphene concentrations. New developments in mass spectrometric detection using either negative chemical ionization or electron impact modes as well as in multidimensional gas chromatography recently have led researchers to suggest congener-specific approaches. Recently, several nomenclature systems have been developed for toxaphene compounds. Although all systems have specific advantages and limitations, it is suggested that an international body such as the International Union of Pure and Applied Chemistry make an attempt to obtain uniformity in the literature. Toxicologic information on individual chlorobornanes is scarce, but some reports have recently appeared. Neurotoxic effects of toxaphene exposure such as those on behavior and learning have been reported. Technical toxaphene and some individual congeners were found to be weakly estrogenic in in vitro test systems; no evidence for endocrine effects in vivo has been reported. In vitro studies show technical toxaphene and toxaphene congeners to be mutagenic. However, in vivo studies have not shown genotoxicity; therefore, a nongenotoxic mechanism is proposed. Nevertheless, toxaphene is believed to present a potential carcinogenic risk to humans. Until now, only Germany has established a legal tolerance level for toxaphene--0.1 mg kg-1 wet weight for fish. (+info)