Endoscopy is of low yield in the identification of gastrointestinal neoplasia in patients with dermatomyositis: A cross-sectional study.

AimTo determine the prevalence of gastrointestinal neoplasia among dermatomyositis patients who underwent an esophagogastroduodenoscopy and/or colonoscopy.MethodsA cross-sectional study examining the results of upper endoscopy and colonoscopy in adults with dermatomyositis at an urban, university hospital over a ten year period was performed. Chart review was performed to confirm the diagnosis of dermatomyositis. Findings on endoscopy were collected and statistical analyses stratified by age and presence of symptoms were performed.ResultsAmong 373 adult patients identified through a code based search strategy, only 163 patients had dermatomyositis confirmed by chart review. Of the 47 patients who underwent upper endoscopy, two cases of Barrett's esophagus without dysplasia were identified and there were no cases of malignancy. Of the 67 patients who underwent colonoscopy, no cases of malignancy were identified and an adenoma was identified in 15% of cases. No significant differences were identified in the yield of endoscopy when stratified by age or presence of symptoms.ConclusionThe yield of endoscopy is low in patients with dermatomyositis and is likely similar to the general population; we identified no cases of malignancy. A code based search strategy is inaccurate for the diagnosis of dermatomyositis, calling into question the results of prior population-based studies. Larger studies with rigorously validated search strategies are necessary to understand the risk of gastrointestinal malignancy in patients with dermatomyositis

A New and Unusual Pathway for the Reaction of Neocarzinostatin Chromophore with Thiols. Revised Structure of the Protein-Directed Thiol Adduct

Neocarzinostatin (holo-NCS) is an antitumor antibiotic comprising a nonprotein chromophore component (1) and a 113- amino acid carrier protein (apo-NCS). Goldberg and coworkers first demonstrated that the reaction of the isolated chromophore (1) with thiols in the presence of double-stranded DNA leads to DNA cleavage by a free-radical mechanism. The pathway shown in Scheme 1 was later proposed to account for this activity, a proposal that is now supported by a considerable body of evidence. In 1992, Saito and co-workers showed that the reaction of holo-NCS with small thiols, such as β-mercaptoethanol (BME), takes a different course, to form a product that is formally a 1:1:1 adduct of thiol, 1, and water. Structure 2 was proposed for this adduct, along with the mechanistic pathway shown in Scheme 2. Complicating the analysis was the fact that 2 was an inseparable mixture of two components, present in equal parts

Policy Implications of a Behavioural Economics Analysis of Land Use Determinants in Rural Scotland

The paper analyses the land use behaviour of Scottish land managers and the factors influencing it in the current context of the EU rural land use policies. The analysis employs a frequently used behavioural economics method, namely structural equation modelling (SEM). Central to the empirical analysis in this paper is a cross-section database containing data collected in May to June 2009 through telephone interviews of 600 land managers in Scotland. The model tests and estimates the relationships between land use behaviour, i.e., behavioural intentions to change the size of business/holding, and several of its a priori determinants found significant in the scientific literature. The results indicate that a stronger propensity to change size of their businesses is exhibited by younger land managers who intend to pass their land on to family, with larger land size and stronger attitudes towards increasing it, with lower percentage of their income made up from Government support, who are less likely to have perceived changes in regulation and input/output prices as having an impact on their business, who discuss and plan changes in size of business with their banks/building societies, and frequently access sources of information to help with their strategic decisions.Land use, rural policies, Scotland, structural equation modelling, Land Economics/Use,

Enhanced heat capacity and a new temperature instability in superfluid He-4 in the presence of a constant heat flux near T-lambda

We present the first experimental evidence that the heat capacity of superfluid 4He, at temperatures very close to the lambda point Tλ, is enhanced by a constant heat flux Q. The heat capacity at constant Q, CQ, is predicted to diverge at a temperature Tc(Q)<Tλ at which superflow becomes unstable. In agreement with previous measurements, we find that dissipation enters our cell at a temperature, TDAS(Q), below the theoretical value, Tc(Q). We argue that TDAS(Q) can be accounted for by a temperature instability at the cell wall, and is therefore distinct from Tc(Q). The excess heat capacity we measure has the predicted scaling behavior as a function of T and Q, but it is much larger than predicted by current theory

Most incompetent calf perforating veins are found in association with superficial venous reflux

AbstractPurpose: The indications for surgical perforator interruption remain undefined. Previous work has demonstrated an association between clinical status and the number of incompetent perforating veins (IPVs). Other studies have demonstrated that correction of IPV physiology results from abolition of saphenous system reflux. The purpose of this study was to identify which, if any, patterns of venous reflux and obstruction are particularly associated with IPV. Patients and Methods: Two hundred thirty patients and subjects (103 men, 127 women, 308 limbs) with varying grades of venous disease were examined both clinically and with duplex ultrasound scan. The odds ratios (ORs) for the presence of IPVs were calculated for different anatomical distributions of main-stem venous reflux and obstruction. The base group are those with no main-stem venous disease. Results: There were no significant associations between the proportions of limbs demonstrating IPVs and patient age or sex. The ORs for the presence of IPVs in association with other venous disease are as follows (age/sex adjusted): long saphenous vein reflux, OR = 1.86, range = 1.32-2.63; short saphenous vein reflux, OR = 1.36, range = 1.02-1.82; deep system venous reflux, OR = 1.61, range = 1.2-2.15; superficial system reflux, OR = 3.17, range = 1.87-5.4; and deep system obstruction, OR = 1.09, range = 0.51-2.33. The ORs for combinations of venous disorders were calculated. Combinations of disease produced higher odds for the presence of IPVs than those above, the highest being long saphenous vein, short saphenous vein, and deep reflux combined, OR = 6.85 (95% CI, 2.97-15.83; P =.0001). Conclusions: Although the presence of IPVs is associated with venous ulceration, the highest ORs for the presence of IPVs were found in patients with superficial disease alone or in combination with deep reflux. Many of these may be corrected by saphenous surgery alone. (J Vasc Surg 2001;34:774-8.

Perceptual integration for qualitatively different 3-D cues in the human brain.

The visual system's flexibility in estimating depth is remarkable: We readily perceive 3-D structure under diverse conditions from the seemingly random dots of a "magic eye" stereogram to the aesthetically beautiful, but obviously flat, canvasses of the Old Masters. Yet, 3-D perception is often enhanced when different cues specify the same depth. This perceptual process is understood as Bayesian inference that improves sensory estimates. Despite considerable behavioral support for this theory, insights into the cortical circuits involved are limited. Moreover, extant work tested quantitatively similar cues, reducing some of the challenges associated with integrating computationally and qualitatively different signals. Here we address this challenge by measuring fMRI responses to depth structures defined by shading, binocular disparity, and their combination. We quantified information about depth configurations (convex "bumps" vs. concave "dimples") in different visual cortical areas using pattern classification analysis. We found that fMRI responses in dorsal visual area V3B/KO were more discriminable when disparity and shading concurrently signaled depth, in line with the predictions of cue integration. Importantly, by relating fMRI and psychophysical tests of integration, we observed a close association between depth judgments and activity in this area. Finally, using a cross-cue transfer test, we found that fMRI responses evoked by one cue afford classification of responses evoked by the other. This reveals a generalized depth representation in dorsal visual cortex that combines qualitatively different information in line with 3-D perception

The M-Machine Multicomputer

The M-Machine is an experimental multicomputer being developed to test architectural concepts motivated by the constraints of modern semiconductor technology and the demands of programming systems. The M- Machine computing nodes are connected with a 3-D mesh network; each node is a multithreaded processor incorporating 12 function units, on-chip cache, and local memory. The multiple function units are used to exploit both instruction-level and thread-level parallelism. A user accessible message passing system yields fast communication and synchronization between nodes. Rapid access to remote memory is provided transparently to the user with a combination of hardware and software mechanisms. This paper presents the architecture of the M-Machine and describes how its mechanisms maximize both single thread performance and overall system throughput

A New and Unusual Pathway for the Reaction of Neocarzinostatin Chromophore with Thiols. Revised Structure of the Protein-Directed Thiol Adduct

Neocarzinostatin (holo-NCS) is an antitumor antibiotic comprising a nonprotein chromophore component (1) and a 113- amino acid carrier protein (apo-NCS). Goldberg and coworkers first demonstrated that the reaction of the isolated chromophore (1) with thiols in the presence of double-stranded DNA leads to DNA cleavage by a free-radical mechanism. The pathway shown in Scheme 1 was later proposed to account for this activity, a proposal that is now supported by a considerable body of evidence. In 1992, Saito and co-workers showed that the reaction of holo-NCS with small thiols, such as β-mercaptoethanol (BME), takes a different course, to form a product that is formally a 1:1:1 adduct of thiol, 1, and water. Structure 2 was proposed for this adduct, along with the mechanistic pathway shown in Scheme 2. Complicating the analysis was the fact that 2 was an inseparable mixture of two components, present in equal parts

Minimal Brownian Ratchet: An Exactly Solvable Model

We develop an exactly-solvable three-state discrete-time minimal Brownian ratchet (MBR), where the transition probabilities between states are asymmetric. By solving the master equations we obtain the steady-state probabilities. Generally the steady-state solution does not display detailed balance, giving rise to an induced directional motion in the MBR. For a reduced two-dimensional parameter space we find the null-curve on which the net current vanishes and detailed balance holds. A system on this curve is said to be balanced. On the null-curve, an additional source of external random noise is introduced to show that a directional motion can be induced under the zero overall driving force. We also indicate the off-balance behavior with biased random noise.Comment: 4 pages, 4 figures, RevTex source, General solution added. To be appeared in Phys. Rev. Let