Characterization of a caldesmon fragment that competes with myosin-ATP binding to actin.

The protein caldesmon inhibits actin-activated ATP hydrolysis of myosin and inhibits the binding of myosin*ATP to actin. Afragment isolated from a chymotryptic digest of caldesmon contains features of the intact molecule that make it useful as a selective inhibitor of the binding of myosin ATP complexes to actin without having the complexity of binding to myosin. The COOH-terminal 20 kDa region of caldesmon binds to actin with one-sixth the affinity of caldesmon with a stoichiometry of binding of one fragment per two actin monomers. This contrasts with the 1:6-9 stoichiometry of intact caldesmon. The binding of the 20 kDa fragments to actin is totally reversed by Ca2+-calmodulin and, like intact caldesmon, the 20 kDa fragments are competitive with the binding of myosin subfragments to actin. This competition with myosin binding is largely responsible for the inhibition of ATP hydrolysis, although both the fragments and intact caldesmon also reverse the potentiation of ATPase activity caused by tropomyosin. These polypeptides are useful both in defining the function of caldesmon and in studying the role of weakly bound cross-bridges in muscle. Originally published Biophysical Journal, Vol. 65, No. 2, Aug 199

A close association of body cell mass loss with disease activity and disability in Chinese patients with rheumatoid arthritis

OBJECTIVES: To investigate the association of body cell mass loss with disease activity and disability in rheumatoid arthritis patients. INTRODUCTION: Rheumatoid cachexia, defined as the loss of body cell mass, is important but under-recognized and contributes to morbidity and mortality in patients with rheumatoid arthritis. METHODS: One hundred forty-nine rheumatoid arthritis patients and 53 healthy, non-rheumatoid arthritis control subjects underwent anthropometric measurements of body mass index and waist and hip circumferences. Bioelectrical impedance analysis was used to determine the subjects' body compositions, including fat mass, skeletal lean mass, and body cell mass. The disease activity of rheumatoid arthritis was assessed using C-reactive protein serum, the erythrocyte sedimentation rate and the 28-joint disease activity score, while disability was evaluated using a health assessment questionnaire. RESULTS: Rheumatoid arthritis patients had lower waist-to-hip ratio (0.86 ± 0.07 vs. 0.95 ± 0.06; p<0.001) and lower skeletal lean mass indexes (14.44 ±1.52 vs. 15.18 ± 1.35; p = 0.002) than those in the healthy control group. Compared with rheumatoid arthritis patients with higher body cell masses, those with body cell masses lower than median had higher erythrocyte sedimentation rates (40.10 ± 27.33 vs. 25.09 ± 14.85; p<0.001), higher disease activity scores (5.36 ± 3.79 vs. 4.23 ± 1.21; p = 0.022) and greater disability as measured by health assessment questionnaire scores (1.26 ± 0.79 vs. 0.87 ± 0.79; p = 0.004). CONCLUSIONS: The loss of body cell mass is associated with higher disease activity and greater disability in rheumatoid arthritis patients. Body composition determined by bioelectrical impedance analysis can provide valuable information for a rheumatologist to more rapidly recognize rheumatoid cachexia in rheumatoid arthritis patients

Gender differences in ankylosing spondylitis-associated cumulative healthcare utilization: a population-based cohort study

BACKGROUND: Ankylosing spondylitis (AS) is one of the most common rheumatic diseases with gender differences in prevalence and clinical presentation. This study aimed to examine whether such gender differences are correlated with cumulative healthcare utilization in Taiwan. METHODS: The National Health Insurance Research Database supplied claim records of one million individuals from 1996 to 2007. Selected cases included patients aged >16 years. Certified rheumatologists diagnosed the patients in three or more visits and gave prescriptions for AS. Multivariate adjusted logistic regression analyses were used to calculate the influence of gender on cumulative healthcare utilization associated with AS. RESULTS: The study included 228 women and 636 men. After adjustment for potential confounding factors, men had more cumulative outpatient visits associated with AS (odds ratio, 1.59; 95% confidence interval, 1.13 -2.23; p = 0.008). Men also exhibited a trend for higher frequency of AS-related hospitalization (p = 0.054). CONCLUSION: Men are more likely to have high cumulative AS-associated healthcare utilization than women. Further investigation of the causal factors is warranted

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome: A case report

AbstractRemitting seronegative symmetrical synovitis with pitting edema (RS3PE) is a rare form of paraneoplastic tenosynovitis, which is more prone to occur in elderly males. A 78-year-old male had a past history of gastric cancer 23 years ago and underwent subtotal gastrectomy then. He led a fair life after the surgery. However, fever, edema in four extremities, gait disturbance, and liver function impairment bothered him for 5 months, which caused significant physical functional decline. Despite of extensive laboratory and imaging examinations, no definite diagnosis and treatment were provided. He was referred to Kyoto University hospital and RS3PE was diagnosed. After the diagnosis of RS3PE syndrome was made, systemic steroid was given and fever, edema and liver function impairment improved dramatically within 7 days. The patient was well managed by oral prednisolone 30mg per day after discharge. RS3PE should be considered when an elderly man with aforementioned presentations in order to prevent significant functional decline in daily living

The Incidence and Prevalence of Thromboangiitis Obliterans in Taiwan: A Nationwide, Population-based Analysis of Data Collected from 2002 to 2011

OBJECTIVE: To estimate the incidence and prevalence of thromboangiitis obliterans in Taiwan in the period spanning from 2002 to 2011. METHODS: We identified all incident and prevalent cases with a diagnosis of thromboangiitis obliterans (International Classification of Diseases, Ninth Revision code 443.1) in the period spanning from 2002 to 2011 using Taiwan’s National Health Insurance Research Database. We calculated the age- and sex-specific incidence and prevalence rates of thromboangiitis obliterans during the study period. RESULTS: From 2002 to 2011, 158 patients were diagnosed with thromboangiitis obliterans; of these, 76% were men. Most (63%) of the patients wer

The Artificial Neural Networks Applied to Servo Control Systems

This chapter utilizes the direct neural control (DNC) based on back propagation neural networks (BPN) with specialized learning architecture applied to the speed control of DC servo motor. The proposed neural controller can be treated as a speed regulator to keep the motor in constant speed, and be applied to DC servo motor speed control. The proposed neural control applied to position control for hydraulic servo system is also studied for some modern robotic applications. A tangent hyperbolic function is used as the activation function, and the back propagation error is approximated by a linear combination of error and error!s differential. The simulation and experiment results reveal that the proposed neural controller is available to DC servo control system and hydraulic servo system with high convergent speed, and enhances the adaptability of the control system

The Hot and Clumpy Molecular Cocoon Surrounding the Ultracompact HII Region G5.89-0.39

We present observations of CH3CN (12-11) emission at a resolution of 2" toward the shell-like ultracompact HII region G5.89-0.39 with the Submillimeter Array. The integrated CH3CN emission reveals dense and hot molecular cocoon in the periphery of the HII region G5.89-0.39, with a CH3CN deficient region roughly centered at G5.89-0.39. By analyzing the CH3CN emission using population diagram analysis, we find, for the first time, a decreasing temperature structure from 150 to 40 K with the projected distance from Feldt's star, which is thought to be responsible for powering the HII region. Our results further indicate that the majority of the heating energy in the observed dense gas is supplied by the Feldt's star. From the derived CH3CN column density profile, we conclude that the dense gas is not uniformly-distributed but centrally-concentrated, with a power-law exponent of 5.5 for r < 8000 AU, and 2.0 for 8000 AU < r < 20000 AU, where r is the distance to Feldt's star. The estimated large power index of 5.5 can be attributed to an enhancement of CH3CN abundance in the close vicinity of Feldt's star.Comment: accepted for publication in The Astrophysical Journal Letter

Hard probes in isobar collisions as a probe of the neutron skin

We present an estimate of the yield of hard probes expected for collisions of the isobars $^{96}_{44}$Ru and $^{96}_{40}$Zr at collision energies reachable at RHIC and the LHC\@. These yields are proportional to the number of binary nucleon-nucleon interactions, which is characteristically different due to the presence of the large neutron skin in $^{96}_{40}$Zr. This provides an independent opportunity to measure the difference between the neutron skin of $^{96}_{44}$Ru and $^{96}_{40}$Zr, which can provide an important constraint on the Equation of State of cold neutron-rich matter.Comment: 5 pages, 6 figures and an appendix. Comments are welcom