Cobalt Levels and Pseudotumor Characteristics Vary due to Metal Ion Source: Modular Femoral Neck vs Metal-on-Metal Articulations

BACKGROUND

This study examines cobalt levels and pseudotumor characteristics in a non-recalled modular femoral prosthesis. We sought to determine relationships between serum cobalt levels and pseudotumors following modular and metal-on-metal (MoM) total hip arthroplasty (THA), the location and size of pseudotumors, and changes to pseudotumor grade over time.

METHODS

We retrospectively evaluated a cohort of 190 primary THAs implanted with a dual-modular femoral stem by one surgeon from 2005 to 2013. One hundred seventeen THAs used a cobalt-chromium modular neck (CoCrMN) component and non-MoM articulation, 63 THAs had a titanium neck component and MoM articulation, and 10 had a titanium neck component and polyethylene liner. Serum ion levels were recorded for all patients. Pseudotumor grade and location were measured by musculoskeletal-trained radiologists.

RESULTS

Cobalt levels did not correlate to time after index arthroplasty. In the CoCrMN group, cobalt levels were elevated in 11 of 19 (57.9%) patients with pseudotumor compared to 14 of 19 (73.7%) in the MoM group. Pseudotumors were more often located lateral to the hip joint in the CoCrMN group compared to anteromedial following MoM arthroplasty. In CoCrMN THAs, pseudotumors were visualized in 12 of 51 (23.5%) initial MARS MRIs within 40 months compared to 5 of 66 (7.6%) performed later (P = .02).

CONCLUSION

Pseudotumor characteristics differ between patients with CoCrMN designs vs those with an MoM articulation. Normal serum cobalt levels did not exclude the presence of a pseudotumor and routine MARS MRI should be included in follow-up of patients with this CoCrMN prostheses.

Altered cytokine expression in tissues of mice subjected to simulated microgravity

Space flight is known to induce microgravity-associated immune dysfunction in humans, non-human primates and rodents. To understand the mechanism underlying these defects, several studies in rodents have been conducted in a ground-based antiorthostatic suspension (AOS) model that would mimic the effects of microgravity. In all these in vivo studies that showed the effects on cytokine profiles actually investigated the ex vivo production from culturing the cells isolated from whole organism that was exposed to space flight and/or microgravity. So, the purpose of the study was to examine the in vivo expression of cytokines in mice in immunologically important tissue environments of mice that were subjected to AOS. Cytokines such as Interleukin-1beta, (IL-1beta), IL-2, IL-3, IL-6, Interferon-gamma (IFN-gamma) and Tumor Necrosis Factor-alpha (TNF-alpha) were measured by Enzyme Linked Immunosorbent Assay (ELISA) in the homogenates of spleen tissue, lymph nodes and also in serum of AOS mice and compared with that of control mice. AOS induced no change in the IL-3 levels, but IL-1beta was increased significantly whereas IL-2 levels decreased in spleen, lymph nodes and serum. IL-6 levels did not differ in spleen but were significantly increased in lymph nodes and serum of AOS mice. IFN-gamma levels in spleen did not change but showed nonsignificant reduction in lymph nodes and significant reduction in serum in response to AOS. TNF-alpha levels in spleen and serum were unchanged and increased in lymph nodes. This in vivo cytokine study confirms the earlier findings that microgravity-simulated conditions induce tissue-specific immune response.

The relative importance of sexual reproduction versus clonal spread in an aridland bunchgrass

Festuca idahoensis (Idaho fescue) is a perennial caespitose grass, common in semi-arid rangelands of the Intermountain West. To determine how individuals are recruited into a population, we studied two long-term monitoring plots that were established in 1937 at the Northern Great Basin Experimental Range in southeastern Oregon. The plots measured 3.05x3.05 m, and were located approximately 30 m apart. One plot was ungrazed, the other was subject to moderate levels of cattle grazing. The number of F. idahoensis plants in both plots increased ten-fold between 1937 and 1996, but whether this was due primarily to reproduction by seed or clonal fragmentation was unknown. In 1996, we mapped and sampled 160 plants of F. idahoensis. We used dominant inter-simple sequence repeat (ISSR) markers and codominant allozyme markers in order to identify genetic individuals and measure genetic diversity. Both plots were characterized by high levels of genetic and clonal diversity. When information from ISSRs, allozymes and sample location were combined, 126 genets were recognized, each consisting of one to four samples (ramets). By measuring the diameter of clones surrounding plants that were present in 1937, we estimated that clonal spread occurred at a rate of approximately 3.7 cm per decade, and thus was of secondary importance in the maintenance and increase of F. idahoensis stands. Sexual reproduction, rather than clonal fragmentation, accounted for most of the recruitment of new plants into these plots. The grazed plot had fewer ramets, genotypes, and clones than the ungrazed plot, but the ramets were significantly larger. Levels of genetic diversity did not differ in the grazed and ungrazed plots, but there was some evidence for a small, but significant level of genetic differentiation between the two. The results also indicate that F. idahoensis has the potential to be a long-lived species with some individuals persisting in excess of 60 years. This study demonstrates how long-term monitoring can be supplemented by genetic analysis to obtain detailed information on the population dynamics of plants. In the case of this community dominant species, this provides essential information for understanding succession and developing management and restoration strategies.

Vocational rehabilitation outcomes of veterans with substance use disorders in a partial hospitalization program

The authors examined factors that influenced the employment rates of 529 veterans with severe alcohol and other substance use disorders who were being treated at an addictions partial hospitalization program. The employment rate was significantly higher for veterans who completed the hospitalization program, participated in a Veterans Industries work-for-pay program, and received drug-free supportive housing.

Music therapy assessment in school settings: a preliminary investigation

The present investigation was undertaken in response to music therapists working in school settings for information relating to the availability of music therapy assessments and the feasibility of standardizing an assessment instrument for music therapists to use in school settings. Five research questions were identified, and the music therapy literature was surveyed to compile responses to those questions. Three different online data bases (ERIC, PsycINFO, and Article 1st) were used, covering articles published between 1980 and 1997. Individual hand searches were done of the Arts in Psychotherapy, Journal of Music Therapy, Journal of Research in Music Education, Journal of the International Association of Music for the Handicapped, Music Therapy and Music Therapy Perspectives. The questions and responses were as follows: 1. Which music-based assessment tools are being used with children with disabilities? Little commonality in assessment tools being used by music therapists and researchers was discovered. Of the total 41 studies, 20 (49%) reported using a "named" or "titled" assessment tool, and in the remaining 51% of studies, the authors reported using an untitled, and usually experimenter-designed, original assessment tool. 2. Have certain assessments been used in more than one study? Very limited replication of existing assessments was found. Of the 16 "named" assessments, only 3 were found to be used in more than one research study. 3. Are the actual assessments published along with the articles describing their use? Only 3 of the 20 studies using named assessments were published along with the journal article. Of the remaining 21 studies using original, experimenter-designed assessment tools, only 6 (28%) had the assessment instrument published with the article. 4. What is the primary purpose for using the assessment? Six primary purposes emerged from the review of the literature: to compare with data obtained from other assessment measures or from other populations (39%), as a baseline or pretest measure (29%), to determine eligibility for services or the receipt of treatment (12%), to determine the psychometric properties of the assessment (7%), suitability of the instrument for the given population (7%), and the identification of musical preferences (5%). 5. What are the musical or nonmusic elements being assessed? Musical elements were: music perception (37%), musical aptitude (29%), musical preferences (12%), and attention to/enjoyment of music (2%). Nonmusical behaviors/responses were: self-expression (10%), motor responses (10%), behavioral responses (7%), cognitive development (2%), and acts of communication (2%). 6. What subject populations are being assessed? Subject populations were: children with developmental disabilities/mental retardation (44%), children with autism (10%), children with hearing impairments (17%), "psychiatric" clients or emotionally disturbed (22%), individuals described as "handicapped" (5%), individuals with physical disabilities (2%), and a student with a speech impairment (2%). Nondisabled individuals were also included in 12 of the aforementioned studies.

The management of self-inflicted burn injuries and disruptive behavior for patients with borderline personality disorder

One of the greatest behavioral and ethical challenges faced by a burn team is the treatment of a patient whose burn injury is the result of parasuicidal behavior. Parasuicidal behavior is defined as intentional self-injurious behavior that, although not fatal, may result in tissue damage or risk of death. There are a number of reasons, usually psychiatric, that patients engage in parasuicidal behavior; however, our contention is that the majority of these patients have a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis II diagnosis of borderline personality disorder. We describe the nature of borderline personality disorder and how it leads to disruptive behavior, including self-harm behavior, on the burn unit, We also argue that if staff members fail to recognize the borderline personality disorder diagnosis, it will lead to responses from staff that can heighten disruptive behavior. We present a series of recommendations for treating such patients with burns and an illustrative case report.

Monitoring Wadi El Raiyan lakes of the egyptian desert for inorganic pollutants by ion-selective electrodes, ion chromatography, and inductively coupled plasma spectroscopy

Wadi El Raiyan is a great depression located southwest of Cairo in the western desert of Egypt, one of the most arid regions of the world. In 1973, Wadi El Raiyan was connected with the agricultural wastewater drainage system of the El Faiyum province to provide a reservoir for the wastewater that exceeded the capacity of Lake Qarun north of the province. Pollutants from agricultural waste including pesticides and fertilizers as well as other effluents of industrial activities and runoffs certainly will pass into the biotic elements of the ecosystem. This report presents the status of inorganic pollutants including anions, cations, and trace metals in the two lakes and the surrounding springs of Wadi El Raiyan using ion chromatography, ion-selective electrodes, and inductively coupled plasma emission spectroscopy. The report also includes the levels of selected metals in the vegetation community of the area. The result of this investigation revealed a great improvement in water quality of the Wadi El Raiyan lakes compared to 1988 report by Saleh et al. Mercury was not detected in any of the samples and the level of lead was significantly reduced. Cadmium levels were much higher than those seen earlier. The higher level of cadmium might be used as an indicator to track the contamination of water by human waste. Concentrations of common anions were not significantly different from those reported earlier. However, an increase in the level of cyanide was observed. Levels of heavy metals in vegetation around the lakes were also found to be lower than previously reported.

Analysis of metal pollutants in the Houston Ship Channel by inductively coupled plasma/mass spectrometry

Trace metal pollutants in the surface water of the Houston Ship Channel were determined using inductively coupled plasma/mass spectrometry (ICP/MS). Metal concentrations varied according to sampling sites. Barium, cobalt, chromium, molybdenum, silver, beryllium, antimony, lead, and mercury concentrations were relatively similar throughout the channel averaging 83.25, 0.55, 6. 31, 6.66, 0.02, 0.017, 3.61, 0.68, and 0.055 microg/L, respectively. Titanium, manganese, copper, zinc, nickel, and selenium concentrations were found to be higher at stations closer to the Galveston Bay (as the water is turning from relatively fresh water to sea water) with concentration ranges of 102.5-351.7, 0.3-25, 0. 3-25, 30-280, 16-77, 6.2-26.5, and 0.0-6.2 microg/L, respectively. Aluminum was found to be much higher at the Buffalo Bayou station (341 microg/L) followed by the San Jacinto station (104 microg/L) with an average of 42 microg/L in the other two stations. Vanadium was found to be unusually high at the Washburn Tunnel station (116 microg/L) and at much lower concentrations in the other three stations, averaging 6.5 microg/L. Iron was also higher at the Buffalo Bayou station (143 microg/L) but was absent at the Lynchburg Ferries station. Arsenic was not found at the Lynchburg and San Jacinto stations. However, arsenic had similar concentrations of 1. 983 and 1.835 microg/L at Buffalo Bayou and Washburn Tunnel, respectively. Cadmium was higher at the Lynchburg Ferries station (3. 3 microg/L) and ranged from 0.3 to 0.96 microg/L in the other locations. Thallium was not found in any of the stations.

Cardiodynamic response to psychological and cold pressor stress: further evidence for stimulus response specificity and directional fractionation

In the present study 36 police officers were exposed to a psychological stressor (IQ quiz) and to cold pressor stress while several cardiovascular variables were monitored. Impedance cardiography was used to provide measures of heart rate, stroke volume, cardiac output, myocardial contractility, and total peripheral resistance. In addition, measures of systolic and diastolic blood pressure and peripheral skin temperature were obtained. A multivariate analysis of variance (MANOVA) indicated that significant increases in diastolic and systolic blood pressure during the cold pressor test were mediated by large increases in total peripheral resistance, whereas blood pressure elevation during the IQ quiz were accompanied by significant increases in heart rate and, to a lesser extent, cardiac output. Peripheral skin temperature decreased in response to each stressor. Additional analysis indicated a degree of stimulus specificity for several variables. For example, diastolic blood pressure showed greater increases to cold pressor than quiz, whereas systolic blood pressure increased more with the psychological than the physical stressor. Directional fractionation occurred for both myocardial contractility and cardiac output.

Antihypertensive therapy and quality of life: a comparison of atenolol, captopril, enalapril and propranolol

This randomized, double-blind parallel study compared the effects of atenolol, captopril, enalapril and propranolol in 360 men with mild-to-moderate essential hypertension. Patients were titrated until diastolic blood pressure (Korotkoff phase V) decreased by at least 10 mmHg or to 90 mmHg or less. Quality of life assessments, based on validated psychometric questionnaires and objective measurements of cognitive function, occurred after three study phases: placebo run-in (3-5 weeks), titration (1-4 weeks), and maintenance (4 weeks). After four weeks of maintenance therapy, atenolol, captopril and enalapril generally had equivalent effects on quality of life, as measured by psychometric questionnaires, whereas propranolol consistently evidenced worsening or less improvement. Global scores of distressing psychological symptoms differed as a function of specific treatment (P = 0.01), with improvements significantly better for the atenolol, captopril and enalapril groups as compared with the propranolol group. There were no statistically significant differences among treatments for changes in cognitive function at maintenance. Thus, the quality of life questionnaires differentiated among drugs of the same class, indicating that selection among antihypertensive drugs should be based on their specific qualities, not on general class characteristics.

Characterization of Brucella abortus soluble antigen employed in immunoassay

A soluble antigen extract of Brucella abortus (BASA) has been prepared by the National Veterinary Services Laboratories and furnished to a number of workers who are examining antibody-mediated and cell-mediated immune responses of cattle infected with B. abortus. Three lots of BASA were examined. There were quantitative but not qualitative differences among lots by content of protein, total carbohydrate, hexose, fatty acid, and 2-keto-3-deoxyoctonic acid. The presence of smooth lipopolysaccharide was demonstrated by the presence of 2-keto-3-deoxyoctonic acid and lipid, by Limulus lysate gelation activity, and by formation of characteristic lipopolysaccharide precipitates in immunoelectrophoresis. A polysaccharide antigen as well as two nonsurface antigens, A2 and C, were also identified. BASA is a satisfactory antigen for use in the enzyme-linked immunosorbent assay since the smooth lipopolysaccharide component bound to polystyrene and functioned in the test. Normal murine spleen cells showed a mitogenic response to BASA similar to that produced by purified smooth lipopolysaccharide. BASA has been used in other laboratories to stimulate peripheral blood leukocytes from cattle infected with B. abortus. Because BASA is a mixture of antigenic components shown to have mitogenic effects in the mouse system, questions on the nature of its stimulatory effect on bovine cells are raised.

Regulation of D-xylose and D-arabitol catabolism by Aerobacter aerogenes

Aerobacter aerogenes strain PRL-R3 possesses inducible enzyme pathways for the catabolism of d-xylose and d-arabitol. d-Xylose is the apparent inducer for d-xylose isomerase and d-xylulokinase. d-Arabitol is the apparent inducer for d-arabitol dehydrogenase and a separate d-xylulokinase. Both kinases had similar K(m) values and substrate specificities, and could not be separated by sucrose gradient centrifugation or polyacrylamide gel electrophoresis. They could be differentiated, however, by their separate regulation, their inhibition by antisera, and by the cold sensitivity of the kinase of the d-arabitol catabolic pathway.