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The American College of Rheumatology is currently defining standards for diagnosis of various rheumatic disorders, so that these diseases may be diagnosed and reported in a uniform fashion. Criteria for systemic sclerosis, rheumatoid arthritis, systemic lupus erythematosus, and osteoarthritis (OA) of the knee have already been defined, among others. This article reports the criteria that have been identified for diagnosis of OA of the hands. These were obtained by a study of 100 patients with OA of the hands and of 99 control patients with hand symptoms, 74 percent of whom had rheumatoid arthritis. OA was considered to be present if there was hand pain, aching, or stiffness, and enlargement of hard tissue surrounding 2 of 10 particular finger joints (5 on each hand), and fewer than 3 swollen metacarpophalangeal joints (these join the base of each finger to the hand), and either enlargement of hard tissue of 2 or more of the outermost finger joints or deformity in at least 2 of the 10 selected finger joints. This classification tree identified 92 percent of all OA cases, and was 98 percent specific in identifying only true OA cases. In contrast, a more traditional classification method which used similar standards, while 94 percent sensitive, was only 87 percent correct in identifying only true OA cases. X-ray findings were less sensitive and less specific, as 31 X-rays of control and OA patients showed no abnormalities. (Consumer Summary produced by Reliance Medical Information, Inc.)

As the field of artificial intelligence advances, the demand for algorithms that can learn quickly and efficiently increases. An important paradigm within artificial intelligence is reinforcement learning1, where decision-making entities called agents interact with environments and learn by updating their behaviour on the basis of the obtained feedback. The crucial question for practical applications is how fast agents learn2. Although various studies have made use of quantum mechanics to speed up the agent’s decision-making process3,4, a reduction in learning time has not yet been demonstrated. Here we present a reinforcement learning experiment in which the learning process of an agent is sped up by using a quantum communication channel with the environment. We further show that combining this scenario with classical communication enables the evaluation of this improvement and allows optimal control of the learning progress. We implement this learning protocol on a compact and fully tunable integrated nanophotonic processor. The device interfaces with telecommunication-wavelength photons and features a fast active-feedback mechanism, demonstrating the agent’s systematic quantum advantage in a setup that could readily be integrated within future large-scale quantum communication networks.

We review empirical studies bearing on the effects of parasites on the age of maturity of their hosts. The few cases already published support theoretical predictions, namely a decrease of host prereproductive life-span unless parasites are benign. Host responses may be due either to phenotypic plasticity or to genetic differences, and even though very few studies on this topic have already been published both mechanisms occur. Promising areas of research include the distribution of age-specific potential costs of resistance to parasitism, as well as the evolution of age-specific parasite preferences under the concomitant evolution of host life-history traits.

Large-scale optical systems in silicon can become a reality by building upon the existing infrastructure. Due to the shifting economics of silicon photonics, some cost-effective fabless silicon products may even emerge over the next several years.

Osteoporosis and fractures are a common consequence of glucocorticoid therapy for inflammatory disorders. Men fracture approximately 10 yr later in life than women and receive less attention as regards osteoporosis risk, including in glucocorticoid-induced osteoporosis (GIOP). In addition, while men are less likely to have certain rheumatologic disorders often treated with glucocorticoids, men are more likely to have chronic obstructive pulmonary disease, inflammatory bowel disease, and organ transplantation as reasons for use of oral glucocorticoids. Attempts to improve recognition of GIOP in general have not been successful, and since men are considered less at risk for osteoporosis in general, attention to men with GIOP is even less. Evaluation of GIOP is similar in men and women, and most modern treatment studies of GIOP have included men. Thus, alendronate, risedronate, and zoledronic acid are Food and Drug Administration (FDA)-approved bisphosphonates for GIOP in men. Teriparatide is also FDA-approved for GIOP. In one 36-month trial of teriparatide vsalendronate for GIOP in men and women, the anabolic agent led to a greater increase in bone density and was associated with a lower incidence of morphologic vertebral fractures. Thus, while good management is available for GIOP, recognition of men at risk is the most important step in improving outcomes.

We describe the design of a silicon-based source for radiation in the 0.5-14 THz regime. This new class of devices will permit continuously tunable, milliwatt scale, cw, room temperature operation, a substantial advance over currently available technologies. Our silicon terahertz generator consists of a silicon waveguide for near-infrared radiation, contained within a metal waveguide for terahertz radiation. A nonlinear polymer cladding permits two near-infrared lasers to mix, and through difference-frequency generation produces terahertz output. The small dimensions of the design greatly increase the optical fields, enhancing the nonlinear effect. The design can also be used to detect terahertz radiation.

It is not yet clear if corticosteroids are useful for the treatment of migraine. We determined the efficacy of 10 mg of IV dexamethasone as adjuvant therapy for patients presenting to an emergency department (ED) with acute migraine.

COX-2 selective inhibitors were developed in order to provide similar efficacy to traditional nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) but with improved upper gastrointestinal safety. This paper presents an overview of randomized clinical trials demonstrating the efficacy of COX-2 selective inhibitors for the treatment of patients with arthritis, particularly osteoarthritis and rheumatoid arthritis. In osteoarthritis and rheumatoid arthritis, COX-2 selective inhibitors have been shown to be more effective than placebo and similarly effective as standard doses of nonselective NSAIDs. There are currently few randomized clinical trials comparing the efficacy of the 2 first-generation COX-2 selective inhibitors, celecoxib and rofecoxib, in osteoarthritis. Of 4 head-to-head studies comparing the 2 agents, 3 indicated similar efficacy, while the other demonstrated superiority of rofecoxib at a dose of 25 mg qd compared with celecoxib at a dose of 200 mg qd. There are no clinical trials comparing the efficacy of different agents for treatment of patients with rheumatoid arthritis. Some studies have also demonstrated efficacy for COX-2 selective inhibitors in patients with ankylosing spondylitis and gout. In aggregate, these data show that COX-2 selective inhibitors provide effective relief of pain in patients with osteoarthritis and rheumatoid arthritis, with efficacy that is similar to traditional NSAIDs. Costeffectiveness and cost-utility studies suggest, however, that their use should be limited to patients at high risk of serious upper gastrointestinal side effects, including complicated ulcers.

Objective:The aim of this study was to evaluate the reliability of a software tool that assesses knee cartilage volumes using magnetic resonance (MR) images. The objectives were to assess measurement reliability by: (1) determining the differences between readings of the same image made by the same reader 2 weeks apart (test–retest reliability), (2) determining the differences between the readings of the same image made by different readers (between-reader agreement), and (3) determining the differences between the cartilage volume readings obtained from two MR images of the same knee image acquired a few hours apart (patient positioning reliability).

ObjectiveWe assessed the probability that mid-aged women with a Kellgren and Lawrence (K–L) score of 1 are likely to progress to a score of 2 or regress to a score of zero at a second time point, 2–3 years later.

Discrepancies exist between radiographic osteoarthritis of the knee (OAK) and report of knee joint pain. Little is known about how these two definitions of osteoarthritis (OA) and their correlates differ between African American (AA) and Caucasian (CA) women.

Objectives. Knee osteoarthritis (OA) is a major cause of disability, particularly in the elderly. The factors determining disability remain unclear. The aim of this study was to assess the impact of clinical and psychosocial variables on function in knee OA and to develop models to account for observed variance in self‐reported disability.Methods. The subjects (n = 69) were hospital out‐patients. Self‐reported disability was measured by the Western Ontario and McMaster Universities (WOMAC) OA index. Pain was measured by the WOMAC and the McGill pain questionnaire. Depression, anxiety, helplessness, self‐efficacy, fatigue and quality of life were measured by standard instruments. A detailed knee examination, including pain threshold by dolorimetry, was performed. Radiographs were scored for individual features.Results. Pain severity, obesity and helplessness were the most important determinants of disability: a model including these variables accounted for 59.9% variance in WOMAC disability. Anxiety remained associated with disability in some models. Disability was unrelated to radiographic change.Conclusions. Function in symptomatic knee OA is determined more by pain and obesity than by structural change, at least as seen on plain X‐ray. Our study provides further support for interventions targeting anxiety and helplessness in knee OA.

The objective of this article was to estimate the prevalence of Paget's disease of bone in the United States from a statistically derived sample of the general population. Pelvic radiographs obtained in the First National Health and Nutrition Examination Survey (NHANES‐I) were reviewed for the presence of Paget's disease. Age, sex, and geographic distribution of Paget's disease of the pelvic region were determined. The overall prevalence of Paget's disease in the United States was estimated. Pelvic Paget's disease is estimated to be present in 0.71 + 0.18% of the radiographs of the general population. The disease was higher in frequency in people who were in the older decades of life with the highest prevalence of 2.32 + 0.54% in the 65‐ to 74‐year‐old people. There is a slight male predominance in the 45‐ to 74‐year age group. The regional distribution suggests the highest prevalence in the Northeast (1.48 + 0.52%) with the lowest prevalence in the South (0.26 + 0.25%). The prevalence was equal in white people and black people. An estimate of the overall prevalence of Paget's disease in the United States was at least 1% and perhaps as much as 2% of the general population with near equal sex distribution and the highest prevalence in the northeastern United States.

Osteoarthritis (OA) has been characterized as a slowly evolving degenerative disease affecting cartilage and bone, with a multifactorial etiology that may differ depending on the joint site. Because OA has been considered a disease of the elderly, few population-based studies have examined its frequency and characteristics in persons under the age of 45.

Most severity indices of osteoarthritis (OA) include measures of physical function which render them unsuitable for assessing the impact of OA on disability. Data from 1002 moderate to severely disabled community-dwelling women ≥65 years were used to develop hand OA severity indices which are independent of functional status. Baseline exams and strength tests were conducted by trained nurse examiners. Each distal and proximal interphalangeal joint, and first carpo-metacarpal joint (20 joints in all) was scored for the presence of a) bony enlargement or deformity, and b) pain on motion or tenderness on palpation. Severity indices were then created: Deformity index (DEF) = sum of joints with bony changes (0–20); Pain/Tenderness index (PT) = sum of joints with pain or tenderness (0–20); and Combined Deformity/Pain index = sum of DEF and PT (0–40). These indices were then validated against grip and pinch strength. All three indices showed a significant trend for weaker grip strength as severity index scores increased. When the 25th, 50thand 75thpercentiles were used to divide each severity index into levels of involvement, a threshold effect was observed with significantly poorer grip strength performance above the 75thpercentile for each index. Similar results were seen for pinch strength. In conclusion, these hand OA severity indices, based on examination findings alone, help distinguish disease status, and may provide a valuable research tool for investigating the role of hand OA in impairment and disability.

Objective: The purpose of this study was to investigate the efficacy of acupuncture as an adjunctive therapy to standard care for the relief of pain and dysfunction in elderly patients with osteoarthritis (OA) of the knee.Methods: Seventy-three patients with symptomatic OA of the knee were randomly assigned to treatment (acupuncture) or standard care (control). Analysis was performed on last score carried forward to account for patients who dropped out before completion. Patients self-scored Western Ontario and McMaster Universities Osteoarthritis Index WOMAC) and Lequesne indices at baseline and at 4, 8 and 12 weeks. Patients in the control group were offered acupuncture treatment after 12 weeks. The data for these patients are pooled with those from the original acupuncture group for within-group analysis.Results: Patients randomized to acupuncture improved on both WOMAC and Lequesne indices compared to those who received standard treatment alone. Significant differences on total WOMAC Scale were seen at 4 and 8 weeks. There appears to be a slight decline in effect at 4 weeks after cessation of treatment (12 weeks after first treatment). No adverse effects of acupuncture were reported.Conclusion: These data suggest that acupuncture is an effective and safe adjunctive therapy to conventional care for patients with OA of the knee.Key words: Osteoarthritis, Knee, Acupuncture, Adjunctive therapy, Elderly.

The disappearance of zinc and iron from soil solution after their addition as soluble metal chelates is attributed to adsorption and fixation. The value of the adsorption coefficient, Kd, was estimated from a batch experiment but because of the inaccuracy involved they were evaluated from the breakthrough curves of column experiments using Rehovot sand. FeEDDHA was neither adsorbed nor was its iron fixed by the soil to any significant extent. The fixation of iron applied as FeEDTA was found to be a first order reaction. Assuming that the fixation reaction kinetics is similar in both the solution and the solid phase, then the reaction rate constant can be expressed as k= (k1θ + k2ρKd)/(θ + ρKd), where k1and k2are the reaction rate constants in the liquid and solid phases, respectively. θ is the volumetric water content and ρ is the bulk density. By using 5 different soil/water ratios, the values of k1and k2were found to be 0.0096 h‐1and 0.087 h‐1, respectively. The value of kwas also estimated from the breakthrough curve in a column experiment by using the relative effluent concentration under steady state condition (C/Co)s. The adsorption of ZnEDTA was negligible under the present experimental conditions. Thus k= k1and is independent of the water content and bulk density. This was shown by comparing the results of the two experimental techniques. The value of k1thus found was 0.084 h‐1. The first order model of the fixation reaction of zinc applied as ZnEDTA is applicable for time periods up to 8 to 10 hours.

Metapopulation studies of single species have shown that the size and spatial arrangement of patches of assumed uniformly ‘suitable’ habitat can influence their population dynamics and persistence. We investigated whether variation in the spatial arrangement of ‘suitable’ habitat of varied quality within a single site can affect the abundance and persistence of interacting species. We accomplished this by extending a field–based spatial simulation model of four interacting species at two trophic levels (an endangered butterfly, its larval food–plant, and two ants). The habitat on sites with the same average and range of qualities was rearranged to give varying degrees of local spatial heterogeneity or ‘site ruggedness’. We found that the ant species that acts as host to the butterfly caterpillars decreased with site ruggedness. The impact on the butterfly was more substantial: it often failed to persist on very rugged sites. Despite being free–ranging over the whole area, the butterfly's persistence depends on the arrangement of habitat quality at a finer spatial scale, due to its interactions with species possessing narrower habitat niches and more localized dispersal. Ruggedness also influenced the rate of recovery of the host ant, and hence community structure, for more than a century following the butterfly's extinction.

H.1. symptom modifying drugs: The primary outcome variable is a specific aspect of joint pain, although a 'signal' symptom or some measure of function may also be studied. Trials of drugs with a rapid onset of effect can be as short as 1-4 weeks but may be as long as 12 weeks. Longer trials (up to 2 years) may be needed to evaluate longer-term toxicity, determine optimal long-term dosing regimens, or establish long-term benefit. Supplemental escape analgesia should be minimized, monitored and discontinued prior to evaluation of efficacy. Some agents that provide symptom relief may not provide benefit until weeks after initiation of therapy. Under these circumstances, trials will vary from 3-12 months in length. If the agent is administered in courses, episodic readministration of the drug may be needed in long-term trials. Longer trials (up to 2 years) may be required to exclude toxicity or establish long-term benefit. H.2. structure modifying drugs: These drugs are intended to prevent, retard, stabilize or reverse development of the morphologic changes of OA. Although this has been called 'chondroprotection', the term is misleading and should be avoided, because all structures of the joint are involved in OA, not articular cartilage alone. The benefits of disease modifying therapy may not be apparent until years after the onset of treatment. The selection of high-risk groups may shorten the time of investigation. Improvement in symptoms (i.e., joint pain) is not a requisite for the efficacy of a drug in this category. In these studies, it may be necessary to permit concomitant use of drugs for relief of symptoms (NSAIDs, analgesics). The confounding effects of glucocorticoids and NSAIDs in these trials is not yet understood and very restricted use of IA depocorticosteroids is recommended. Demonstration of structure modification will require the use of direct measures of joint anatomy, such as radiography, particularly measurement of the radiographic joint space. As stated above, the plain radiograph is presently the most reproducible and readily available method for assessment of disease modification. Studies are needed to validate surrogate markers of disease activity, since they may help shorten Phase 2 structure modifying drug trials. As an alternative to radiography, some trials may utilize arthroscopy. As we approach the beginning of the twenty-first century, concepts of clinical trials of OA drugs are changing. Methodology and techniques for the evaluation of new agents for OA have been refined dramatically over the last decade. We look forward to the future with excitement as we anticipate the development of new agents that may alter the symptoms and course of OA. The above recommendations are intended to help us ascertain which of these new agents are effective.

The association of metabolic and physiologic factors with hand osteoarthritis was studied in 888 Caucasian male subjects aged 17-102 years in the Baltimore Longitudinal Study of Aging. Left-hand radiographs taken between 1958 and 1975 were read by one investigator for grade of osteoarthritis using Kellgren-Lawrence scales. Possible risk factors, assessed at the same visit as the last radiograph during this interval, included age and measures of bone mass, body composition, muscle mass, and muscle strength. Results of bivariate analyses of these cross-sectional data showed that increasing grade of hand osteoarthritis was associated with increasing age; greater mean levels of waist/hip ratio and percentage of body fat; and lower mean levels of percentage of cortical area, grip strength, and forearm circumference. After adjustment for age using residuals from best-fit quadratic regression models, none of these independent variables remained significantly associated with grade of hand osteoarthritis. These data fail to support hypotheses that metabolic and physiologic factors are associated with hand osteoarthritis independent of their known age-related changes.

There are a number of ways in which a host can respond in evolutionary time to reductions in survival and reproduction due to a virulent parasite. These include evolving physiological morphological, or behavioural mechanisms of resistance to infection (or to proliferation, once infection has occurred). But a more unexpected tactic is also possible. This is for hosts to reproduce (slightly) sooner when in the presence of a virulent parasite as compared to when the parasite is less virulent or absent. As such, hosts which reproduce younger may be at a selective advantage, since they can both evade parasitism in time and, even when parasitised, can reduce the likely impact of the parasite on survival and reproductive success. We employ a simple mathematical model to propose that parasites and pathogens can act as important agents in the evolution of the timing of reproduction and associated life-history characters (e.g. body size). Once established in a semelparous host population, evolutionary increases in parasite virulence should result in the evolution of shorter lived hosts; whereas the evolution of less virulent forms of the parasite should be accompanied by the evolution of longer lived hosts. We argue that in the presence of a sufficiently virulent parasite the evolution of longer pre-reproductive life-spans should require the previous or concomitant evolution of morphological, behavioural or physiological resistance to parasitic infection and proliferation.

Abstract:: To estimate the prevalence and impact of self-reported hip fracture in elderly women an age-stratified random sample of 3841 community-dwelling women aged 65 years and above were interviewed to determine the occurrence of 13 chronic conditions and difficulty performing 15 tasks. Associations were examined using multiple logistic regression analysis. The weighted prevalence of hip fracture was 4.7 per 100. Prevalence increased with increasing age from 2.9 per 100 in women aged 65–74 years to 12.6 per 100 in women aged 85 years and above, and was higher in white women than black women. Women with hip fracture were significantly more likely to report concomitant Parkinson's disease (age-adjusted odds ratio [aOR] = 2.8) and stroke (aOR = 1.8). After adjustment for potential confounding variables, women with hip fracture were significantly more likely to report difficulty performing 11 activities that map into domains of mobility/exercise tolerance, self-care tasks and higher functioning domains. Hip fracture is common among elderly community-dwelling women and is associated with difficulty in performing activities of daily living.

The authors conducted a population-based case-control study of connective tissue disease in a four-county area in southeastern Georgia. Interviews with 44 cases and 88 controls were conducted in September and October of 1986. The association with a family history of these disorders was reconfirmed, and a positive association with the use of hair dyes was found. A negative association was found with a family history of diabetes mellitus.

Factors associated with hip osteoarthritis were studied in 2,490 subjects aged 55-74 years using data from the First National Health and Nutrition Examination Survey (NHANES-I). Pelvic radiographs were read for hip osteoarthritis using Kellgren-Lawrence scales; cases were defined by grade > or = 2 changes. Subjects with missing radiographs and other data and those with grade 1 radiographic changes (n = 132) were excluded from analyses. Crude and adjusted odds ratios and 95% confidence intervals (CIs) were estimated from logistic regression analyses. Overall, the crude prevalence of hip osteoarthritis was 3.1% (73 of 2,358); 42 cases were unilateral, and 31 cases were bilateral. Age was significantly associated with hip osteoarthritis (adjusted odds ratios = 1.30 (95% CI 0.60-2.81), 1.69 (95% CI 0.83-3.44), and 2.38 (95% CI 1.15-4.92) for ages 60-64, 65-69, and 70-74, respectively). Other sociodemographic factors, obesity, and fat distribution were not associated with hip osteoarthritis. Age and hip trauma were strongly associated with hip osteoarthritis among men; however, among women, no factors were significantly associated with hip osteoarthritis. Hip trauma was significantly associated with unilateral but not bilateral hip osteoarthritis, while obesity was associated with bilateral but not unilateral hip osteoarthritis. These data suggest that etiologic factors associated with hip osteoarthritis may differ for males and females and for unilateral and bilateral hip osteoarthritis.

We have identified two RNA-specific hybridoma autoantibodies in fusions of spleen cells from unimmunized NZB/NZW female mice with BALB/c myeloma cells. The two fusion experiments were carried out 2 years apart with different myeloma partners. Specificity analyses showed that the two monoclonal antibodies and the total RNA-binding IgG in NZB/NZW serum recognize a G,C-rich sequence of ribonucleotides. The isolated heavy and light chains of the two antibodies and their papain Fab fragments could be distinguished by NaDodSO4/polyacrylamide gel electrophoresis. Rabbit anti-idiotypic antibodies prepared against the two monoclonal proteins showed unique specificities for the antigen-binding sites of their cognate auto-antibodies. Moreover, the anti-idiotypic antisera had little effect on the RNA-binding capacity of the total IgG from NZB/NZW serum. These results suggest that a wide range of different idiotypes is involved in the autoimmune response to a similar antigenic determinant.

A neutron small-angle scattering study was performed to determine the thickness and the scattering density profile of isolated peptidoglycan sacculi of Escherichia coli W7 in aqueous suspension (D2O). The maximum thickness (7 +/- 0.5 nm) of the sacculus from the exponential-phase cells was large enough to suggest the existence of a more-than-single-layered architecture. The experimental density profile across the thickness of the sacculus did not allow an unambiguous differentiation between a single-layered architecture characterized by completely extended peptide side chains projecting from the sugar strands or, alternatively, a partially triple layered structure. To resolve this ambiguity, sacculi were labeled with deuterated wall peptides. Comparison of the two experimental profiles indicated that the sacculus is more than single layered across its surface, with about 75 to 80% of its surface single layered and 20 to 25% triple layered.

The movement of iron in the form of FeEDDHA and FeEDTA and zinc in the form of ZnEDTA was studied in columns of Rehovot sand under several flow rates and in the presence of either Ca(NO3)2or KNO3with the same ionic strength of 0.0375M/liter. Chloride was used as a tracer. FeEDDHA was neither adsorbed nor fixed by the soil. Both ZnEDTA and FeEDTA were fixed in the soil column in the presence of Ca2+but not in the presence of K+. ZnEDTA was not adsorbed significantly, whereas FeEDTA was adsorbed in the presence of either KNO3or Ca(NO3)2solutions. Reasonable agreement was obtained between experimental results and theoretical calculations of the breakthrough curves, based on the analytical solution of the general dispersion equation.

A simple column experiment is proposed for the estimation of metal chelate stability under specified conditions such as soil type, pH, and Ca concentration. The metal chelate solution is passed through the soil column and the effluent concentration is measured in a steady state. Assuming a first-order reaction rate for the fixation of the metal (exchange of the metal under study followed by its precipitation) and a linear adsorption isotherm of the metal chelate, the effluent concentration in the steady state is simply related to the reaction rate and to the adsorption coefficient of the metal chelate.