Synovial tissue in rheumatoid arthritis is a source of osteoclast differentiation factor

OBJECTIVE

Osteoclast differentiation factor (ODF; also known as osteoprotegerin ligand, receptor activator of nuclear factor kappaB ligand, and tumor necrosis factor-related activation-induced cytokine) is a recently described cytokine known to be critical in inducing the differentiation of cells of the monocyte/macrophage lineage into osteoclasts. The role of osteoclasts in bone erosion in rheumatoid arthritis (RA) has been demonstrated, but the exact mechanisms involved in the formation and activation of osteoclasts in RA are not known. These studies address the potential role of ODF and the bone and marrow microenvironment in the pathogenesis of osteoclast-mediated bone erosion in RA.

METHODS

Tissue sections from the bone-pannus interface at sites of bone erosion were examined for the presence of osteoclast precursors by the colocalization of messenger RNA (mRNA) for tartrate-resistant acid phosphatase (TRAP) and cathepsin K in mononuclear cells. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to identify mRNA for ODF in synovial tissues, adherent synovial fibroblasts, and activated T lymphocytes derived from patients with RA.

RESULTS

Multinucleated cells expressing both TRAP and cathepsin K mRNA were identified in bone resorption lacunae in areas of pannus invasion into bone in RA patients. In addition, mononuclear cells expressing both TRAP and cathepsin K mRNA (preosteoclasts) were identified in bone marrow in and adjacent to areas of pannus invasion in RA erosions. ODF mRNA was detected by RT-PCR in whole synovial tissues from patients with RA but not in normal synovial tissues. In addition, ODF mRNA was detected in cultured adherent synovial fibroblasts and in activated T lymphocytes derived from RA synovial tissue, which were expanded by exposure to anti-CD3.

CONCLUSION

TRAP-positive, cathepsin K-positive osteoclast precursor cells are identified in areas of pannus invasion into bone in RA. ODF is expressed by both synovial fibroblasts and by activated T lymphocytes derived from synovial tissues from patients with RA. These synovial cells may contribute directly to the expansion of osteoclast precursors and to the formation and activation of osteoclasts at sites of bone erosion in RA.

Patients with Alzheimer's disease who cannot perform some motor skills show normal learning of other motor skills

Previous researchers have claimed that patients with Alzheimer's disease (AD) learn new motor skills normally, although many AD patients cannot perform the tasks and must be eliminated from the analysis. Excluding them assumes that they have a deficit of motor performance (competence to perform the task), but not of motor learning (ability to improve performance). The present study administered 4 motor tasks to 20 AD patients and 20 controls. The results showed that the ability to complete 1 task (performance) did not predict the rate of improvement (learning) on another task, which indicates that AD patients do indeed have a performance deficit and not a general deficit of motor skill learning. Dementia ratings predicted the ability to perform tasks but not the ability to learn them. It is concluded that it is defensible to claim that AD patients learn a motor skill normally, even if some of the patients are unable to perform the task.

Cue for quality

Continuous improvement or CI is an approach to improving quality in an organization's processes on an ongoing basis. Three key components contribute to CI success: (1) draw on the knowledge and abilities of employees at all levels; (2) focus on customer needs; and (3) use data in a scientific approach to decision making. A long-term effort, not a short-term fix, the classic CI cycle is Plan, Do, Study, Act. Health care organizations are finding a good fit for CI in clinical applications. Improved patient care through efficient, consistent processes is one of the immediate, obvious benefits of CI. The data collected can also validate decisions from a financial standpoint and provide necessary information to regulatory agencies. Over the longer term, applying CI data and understanding customer needs can help to develop efficient, user-oriented facilities. The chief payback, however, is an organization that is flourishing because it meets the needs and expectations of customers--patients, physicians, employees, and the community.

Possible acceleration of age effects on cognition following menopause

Many cognitive functions have been shown to deteriorate with age. Because of the importance of the menopause as a milestone in the life cycles of women, we examined whether the aging-over-time process in some cognitive functions differs between women of reproductive age and postmenopausal women. It is demonstrated here that in some cognitive tests, including driving simulation, reaction time and some visuospatial tests, there is a significant acceleration in deterioration of functioning following menopause. It is suggested that this acceleration might be associated with the lack of gonadal hormones or other reproduction-related factors which may play a protective role against age-related deterioration in some cognitive functions in women.

Child abuse notification in a country town

This paper reports a study of child abuse notification in a small remote country town in Queensland, Australia. Aims were to investigate how strongly residents felt about child abuse; how likely they were to notify suspected abuse; indicators of abuse; notification facilitators and inhibitors; and the notification process. A cross-sectional survey design was used involving semi-structured interviews with a simple random sample of 60 living groups. Residents felt strongly about child abuse. They were more likely to notify physical and sexual abuse than neglect and emotional abuse. They emphasized obvious physical indicators, but also recognized behavioral and emotional indicators. Residents would notify primarily out of concern for the child's welfare but would hesitate to notify because of fear of retaliation against the child, because they had a relationship with the suspect family, because the suspect family presented a positive public image, and because respondents valued family privacy. Residents were more likely to notify locally accessible professionals rather than geographically distant statutory authorities. Women were more involved than men in the process, and residents discussed possible notification within their intimate social networks before notifying. Some results are related to the specifically rural context. Implications are developed for rural policy, services and public education.

Central nervous system effects of meclizine and dimenhydrinate: evidence of acute tolerance to antihistamines

Relative daytime drowsiness and performance impairment produced by meclizine and dimenhydrinate was assessed in 24 healthy male volunteers. Subjects received either dimenhydrinate, 100 mg, at 8:00 AM, 12:00 PM, and 4:00 PM; meclizine, 50 mg, at 8:00 AM, with placebo at 12:00 PM and 4:00 PM; or placebo at all three times in this randomized, double-blind, three-way crossover study. Impairment of mental performance was assessed by choice reaction time testing and digit symbol substitution scores. Drowsiness was self-assessed on the Stanford Sleepiness Scale and on a visual analog scale. Both antihistamines produced changes in digit symbol substitution, recognition time, and subjective assessments of sleepiness different from placebo. Expressed as change from baseline, the greatest reductions in digit symbol substitution scores after dimenhydrinate occurred 3 hours after the first dose (6.6 +/- 7) and were not different from the greatest measured change after meclizine (5.8 +/- 8), which occurred 9 hours after the dose was administered. Similar results were obtained with the other psychometric test scores. Self-rated sleepiness after dimenhydrinate was greatest 1 hour after the first dose, and was significantly greater than the largest degree of sleepiness after meclizine, which occurred at 7 hours after the dose. The effects of the first dose of dimenhydrinate on psychometric test scores were compared with the magnitude of the effects produced by subsequent doses. The magnitude of effect of the first dose of dimenhydrinate was significantly greater than the magnitude of effect produced by subsequent doses. The data suggest the possibility that acute tolerance to central nervous system impairment develops with multiple doses of dimenhydrinate.

Pharmacokinetics and metabolism of racemic 2',3'-dideoxy-5-fluoro-3'-thiacytidine in rhesus monkeys

2',3'-Dideoxy-5-fluoro-3'-thiacytidine (FTC) is a nucleoside analog that selectively inhibits human immunodeficiency and hepatitis B viruses in vitro. In this study, the preclinical pharmacokinetics of racemic FTC in rhesus monkeys following intravenous and oral administration were characterized. The terminal half-life of FTC was independent of the route of administration and averaged 1.34 +/- 0.18 h (mean +/- standard deviation). Total clearance of FTC was moderate to high, averaging 1.49 +/- 0.24 liters/h/kg. Qualitative assessment of urine samples suggests that renal excretion of unchanged FTC was the major route of elimination of the nucleoside. The compound was also eliminated by metabolism and the deaminated biotransformation product 2,3'-dideoxy-5-fluoro-3'-thiauridine (FTU) was detected in serum and urine. This metabolite has no antiviral activity in human lymphocytes and liver cells. FTC and the metabolite FTU were conjugated, to a minor extent yielding the corresponding glucuronides. No 5-fluorouracil was detected in serum or urine. This is consistent with chromatographic studies using a chiral column that indicated that when racemic FTC is treated with cellular cytidine-deoxycytidine deaminase, the D-(+)-enantiomer of FTC is slowly deaminated to D-(+)-FTU, whereas the L-(-)-enantiomer is essentially resistant to this enzyme. The steady-state volume of distribution of FTC in serum averaged 2.23 +/- 0.42 liters/kg, and the nucleoside analog was distributed into the cerebrospinal fluid, which suggests that this drug penetrated the blood-brain barrier. Absorption of FTC after oral administration was rapid, with bioavailability averaging 73 +/- 6%. Taken together, the results indicate that the unusual L-(-)-enantiomer of FTC should be evaluated further in rhesus monkeys prior to determination of whether this compound is useful for treatment of human immunodeficiency and hepatitis B virus infections.

A review of the effects of antihistamines on mental processes related to automobile driving

The newer, second-generation H1-receptor antagonists have been shown to have potent antiallergic effects without inducing sleepiness. However, because traditional antihistamines may cause functional or cognitive impairment, the clinician still must consider warning patients about activities that could be hazardous. Because the effects of drugs on driving an automobile are difficult to measure directly, studies must use surrogate activities in a laboratory setting. Effects of antihistamines on the central nervous system are assessed with psychomotor tests, which are selected on the basis of their relativity to real-world activities, to develop a profile of mental processes that may be affected. This article reviews the psychomotor tests and study design used to characterize the intensity and duration of drug effects after single and multiple doses and in combination with other impairing agents such as ethanol. Several studies have been published that assess the effects of cetirizine, an H1-receptor blocker, on mental performance. In the study discussed here, diphenhydramine hydrochloride and hydroxyzine were used as positive controls to demonstrate that the period during which some traditional antihistamines impair performance is different than the period of reported drowsiness they induce. The results of this series of studies show that cetirizine induced minimal changes in mental performance tests and only following the highest (20 mg) dose studied.

The pharmacodynamics of ethanol: effects on performance and judgment

The objective and subjective effects produced by increasing and decreasing ethanol concentrations were studied in healthy volunteers on three separate occasions. A randomized, double-blind, placebo-controlled, four-way crossover study was used to determine whether there is any disparity between the time course of blood ethanol concentration and its effects on either objective test performance or self rated impairment. On each study day the subjects received one of four treatments consisting of either placebo or sufficient alcohol to achieve peak estimated blood alcohol concentration (Est.BAC) of 0.07 gm/dL, 0.1 gm/dL or 0.14 gm/dL. Est.BAC determined from breath alcohol concentrations were measured 20 minutes after each "dose" until peak Est.BAC was achieved, then 1, 2, 3.5, and 4.5 hours after peak Est.BAC. Digit symbol substitution (DSS), simulated driving reaction time (SDRT), choice reaction time (CRT) and self assessment of impairment (SRI) were measured simultaneously with Est.BAC. Changes in objective performance test scores were well correlated with Est.BAC (r2 = 0.60 P less than .01). Maximum impairment in test performance occurred at the same time as peak Est.BAC. Threshold Est.BAC needed to produce changes in objective test scores greater than placebo were 0.06 +/- 0.01 for DSS, 0.04 +/- 0.01 for SDRT, and 0.04 +/- 0.02 for CRT. There was no evidence of between dose or within dose tolerance to the effects produced by various Est.BAC on any of these performance tests. Subjects' self rated degrees of impairment at various Est.BAC were influenced by whether alcohol concentrations were rising or falling. Subjective impairment ratings were greater while alcohol concentrations were increasing compared to the same Est.BAC occurring during falling alcohol concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Jejunal atresia with 'apple peel' deformity. A report of eight survivors

Jejunal atresia with an "apple peel" deformity is one of the most severe forms of intestinal atresia. Until quite recently, neonatal mortality rates as a result of this anomaly were high. Early diagnosis, appropriate surgery, and prolonged parenteral nutrition have led to a spectacular improvement of the survival rates. We are reporting eight cases of apple peel atresia--all eight patients survived. The pathophysiology, diagnostic aspects, surgical approaches, and postoperative management are discussed.

Detection of myocardial scars in neonatal infants from computerized echocardiographic texture analysis

It has been demonstrated that highly reflectile echoes (HREs) on standard echocardiograms may represent foci of myocardial fibrosis, calcification, or infiltration. A pilot study of the echocardiograms of premature infants by our group has indicated the presence of HREs in many stressed infants. We have subsequently shown that these HREs correspond to myocardial scarring or necrosis.

By studying normal two-dimensional echocardiograms and those with visually observed highly reflectile echoes (HREs), we have been able to develop echo-intensity ranges for normal neonatal myocardium and suspected foci of necrosis. An amplitude analysis of the intensity levels of these highly reflectile areas (HREs) in the echocardiogram has indicated that their mean intensity was significantly higher than the surrounding healthy myocardial areas. Significant correlation was found between these highly reflectile echo zones and calcified or necrotic tissue based on postmortem pathological examination.

An objective method of quantifying the ultrasonic reflection amplitude has thereby been developed by us, based on image analysis of the echograms available from the B-scan system. Algorithms have been developed for evaluating the greylevels (or echo intensities or reflection amplitudes) of the pixels, normalizing them with respect to the reflection amplitude of the pericardium, and then printing out the grey-level distribution over an image. Appropriate software has been developed to designate scarred myocardial segments, based on the mean and standard deviation of the selected region on the echo image in comparison with these values for the pericardium.

Antibiotic-resistant group JK bacteria in hospitals

The organisms designated as Center for Disease Control group JK are gram-positive rods that have previously been described as causing serious infection in compromised hosts. Four years of hospital experience with this group of organisms in Clinical Center patients was reviewed. Studies were also undertaken on specific wards to determine frequency of occurrence and distribution patterns. Inguinal cultures taken on two wards showed that 30 to 35% of patients were colonized with group JK and that newly admitted patients may already be colonized at the time of admission. Colonization was shown to persist for weeks and sometimes months. Isolates obtained throughout the hospital were predominantly from cancer patients, particularly in wounds, abscesses, and drainage sites. Most blood isolates were from granulocytopenic patients with hematological malignancies.