TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: Provocative clinical tests are often performed in the diagnosis of ulnar neuropathy at the elbow (UNE) although the evidence for the usefulness of these tests is limited. The aim of this study was to determine the diagnostic value of provocative clinical tests in the diagnosis of UNE in a relevant spectrum of patients and controls.', "A prospective cohort study was performed in consecutive patients clinically suspected of having UNE. All patients underwent a neurological examination and four commonly used provocative clinical tests (Tinel's test, flexion compression test, palpating for local ulnar nerve tenderness and nerve thickening). Subsequently, in all patients a reference standard test comprising electrophysiological studies and neurosonography was independently assessed.", "192 eligible patients completed the study protocol. UNE was diagnosed in 137 and an alternative diagnosis was made in 55 patients. The sensitivity, specificity, and positive and negative predictive values were as follows: Tinel's test 62%, 53%, 77% and 30%; flexion compression test 61%, 40%, 72% and 29%; palpating for nerve thickening 28%, 87%, 84% and 33%; and palpating for nerve tenderness 32%, 80%, 80% and 32%. Logistic regression and receiver operating characteristic curves showed that the added value of one or more provocative tests over routine clinical examination is minimal.\Question: Is the diagnostic value of provocative clinical tests in ulnar neuropathy at the elbow marginal?

SOLUTION: The diagnostic value of provocative clinical tests in UNE is poor.

PROBLEM: Context: Animals control the speed of motion to meet behavioral demands. Yet, the underlying neuronal mechanisms remain poorly understood. Here we show that a class of segmentally arrayed local interneurons (period-positive median segmental interneurons, or PMSIs) regulates the speed of peristaltic locomotion in Drosophila larvae.', 'PMSIs formed glutamatergic synapses on motor neurons and, when optogenetically activated, inhibited motor activity, indicating that they are inhibitory premotor interneurons. Calcium imaging showed that PMSIs are rhythmically active during peristalsis with a short time delay in relation to motor neurons. Optogenetic silencing of these neurons elongated the duration of motor bursting and greatly reduced the speed of larval locomotion.\Question: Does a group of segmental premotor interneurons regulate the speed of axial locomotion in Drosophila larvae?

SOLUTION: Our results suggest that PMSIs control the speed of axial locomotion by limiting, via inhibition, the duration of motor outputs in each segment. Similar mechanisms are found in the regulation of mammalian limb locomotion, suggesting that common strategies may be used to control the speed of animal movements in a diversity of species.

PROBLEM: Context: Chronic inflammation in periodontal disease is associated with increased plasminogen activation and elevated levels of chemokines. It is unknown whether chemokines can regulate the activation of plasminogen via modulation of plasminogen activators (PA) and the corresponding plasminogen activator inhibitors (PAI) in periodontal tissue.', 'To establish a link between chemokines and activation of plasminogen, human periodontal ligament fibroblasts (PDL) and gingival fibroblasts (GF) were incubated with IL-8, monocyte chemoattractant protein-1, macrophage inflammatory protein-1alpha, and platelet factor-4, either alone or in the presence of the inflammatory mediators TGF-beta and IL-1. The potential of the cell lysates to activate plasminogen was based on kinetic studies with the substrate casein. Casein zymography was performed to determine the molecular sizes of the PA. Total PAI-1 in the cell-conditioned medium was quantified by immunoassay.', 'We report that the chemokines did not affect activation of plasminogen by PDL and GF. Even in the presence of TGF-beta which suppressed, and IL-1 which stimulated plasminogen activation, the chemokines had no direct effect. Inhibition of PA and plasmin, but not of matrix metalloproteinases and cysteine proteinases prevented caseinolysis. The plasminogen activation capacity of the cell lysates was represented by a single band with features of uPA. The immunoassay showed that the release of PAI-1 in PDL and GF remained unaffected by the chemokines, also when stimulated with TGF-beta.\Question: Is plasminogen activation by fibroblasts from periodontal ligament and gingiva directly affected by chemokines in vitro?

SOLUTION:
These results suggest that plasminogen activation by PDL and GF is not directly affected by the chemokines even in the presence of the inflammatory mediators TGF-beta and IL-1.