Efficient long-range conduction in cable bacteria through nickel protein wires

Filamentous cable bacteria display long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on individual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating protein shell layer. The core proteins contain a sulfur-ligated nickel cofactor, and conductivity decreases when nickel is oxidized or selectively removed. The involvement of nickel as the active metal in biological conduction is remarkable, and suggests a hitherto unknown form of electron transport that enables efficient conduction in centimeter-long protein structures

Redefining The Notion Of weakness In GR(1) Formulae

Abstract The paper ‘A Weakness Measure for GR(1) Formulae’, by Davide G. Cavezza, Dalal Alrajeh and András György, published in Formal Aspects of Computing, in November 2020, explores a new measure for assessing the weakness of GR(1) conjunctions quantitatively.</jats:p

A Weakness Measure for GR(1) Formulae

AbstractWhen dealing with unrealizable specifications in reactive synthesis, finding the weakest environment assumptions that ensure realizability is often considered a desirable property. However, little effort has been dedicated to defining or evaluating the notion of weakness of assumptions formally. The question of whether one assumption is weaker than another is commonly interpreted by considering the implication relationship between the two or, equivalently, their language inclusion. This interpretation fails to provide any insight into the weakness of the assumptions when implication (or language inclusion) does not hold. To our knowledge, the only measure that is capable of comparing two formulae in this case is entropy, but even it cannot distinguish the weakness of assumptions expressed as fairness properties. In this paper, we propose a refined measure of weakness based on combining entropy with Hausdorff dimension, a concept that captures the notion of size of theω-language satisfying a linear temporal logic formula. We focus on a special subset of linear temporal logic formulae which is of particular interest in reactive synthesis, called GR(1). We identify the conditions under which this measure is guaranteed to distinguish between weaker and stronger GR(1) formulae, and propose a refined measure to cover cases when two formulae are strictly ordered by implication but have the same entropy and Hausdorff dimension. We prove the consistency between our weakness measure and logical implication, that is, if one formula implies another, the latter is weaker than the former according to our measure. We evaluate our proposed weakness measure in two contexts. The first is in computing GR(1) assumption refinements where our weakness measure is used as a heuristic to drive the refinement search towards weaker solutions. The second is in the context of quantitative model checking where it is used to measure the size of the language of a model violating a linear temporal logic formula.</jats:p

Intrarticular treatment of osteoartropaty knee with polynucleotides: a pilot study with medium-term follow-up

Knee osteoarthritis is a major cause of disability in the elderly. Many therapies are nowadays available, ranging from non-pharmacologic to pharmacological approaches like visco-supplementation, oral supplements or topical treatments, but a flawless treatment is still to be found. Visco-supplementation represents a valid treatment option for reducing pain associated with knee osteoarthritis and improving function in the affected joint. Many literature data report on the efficacy and safety profiles of hyaluronic acid in knee osteoarthritis, however the efficacy of intra-articular hyaluronic acid remains controversial, in fact while several clinical trials claimed a disease-modifying effect for hyaluronic acid, subsequent meta-analyses have cast doubts on this fact. The ideal intra-articular treatment for osteoarthritis should not only provide a mechanical protection of the cartilage surface, but also restore condrocytes homeostasis by restoring the physiological articular micro-environment and supplying nutrients. In this perspective an innovative medical product made up of polynucleotides (Condrotide) has been developed. The aim of this study is to test the 2-months efficacy in pain relief and improving function of intra-articular injections of Condrotide in patients with knee osteoarthritis or with grade III or IV chondropathy. Ninety-five subjects (33 men, 62 women), aged between 53 and 80, were included between May 2011 to July 2012. All subjects received intra-articular injections of Condrotide and were evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS), the NRS scale for pain assessment, the measurement of the range of motion (R.O.M.). In all subjects a significant improvement was found in KOOS score after 60 days. The mean global NRS pain decreased in both groups and there was also a R.O.M. improvement. These results show that the intra-articular administration of nucleotides in subjects with both severe knee arthritis and chondropathy can be recommended since is able to reverse in the short and medium term symptoms and function with a significant improvement in quality of life

Intrarticular treatment of osteoartropaty knee with polynucleotides: a pilot study with medium-term follow-up

: Knee osteoarthritis is a major cause of disability in the elderly. Many therapies are nowadays available, ranging from non-pharmacologic to pharmacological approaches like visco-supplementation, oral supplements or topical treatments, but a flawless treatment is still to be found. Visco-supplementation represents a valid treatment option for reducing pain associated with knee osteoarthritis and improving function in the affected joint. Many literature data report on the efficacy and safety profiles of hyaluronic acid in knee osteoarthritis, however the efficacy of intra-articular hyaluronic acid remains controversial, in fact while several clinical trials claimed a disease-modifying effect for hyaluronic acid, subsequent meta-analyses have cast doubts on this fact. The ideal intra-articular treatment for osteoarthritis should not only provide a mechanical protection of the cartilage surface, but also restore condrocytes homeostasis by restoring the physiological articular micro-environment and supplying nutrients. In this perspective an innovative medical product made up of polynucleotides (Condrotide) has been developed. The aim of this study is to test the 2-months efficacy in pain relief and improving function of intra-articular injections of Condrotide in patients with knee osteoarthritis or with grade III or IV chondropathy. Ninety-five subjects (33 men, 62 women), aged between 53 and 80, were included between May 2011 to July 2012. All subjects received intra-articular injections of Condrotide and were evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS), the NRS scale for pain assessment, the measurement of the range of motion (R.O.M.). In all subjects a significant improvement was found in KOOS score after 60 days. The mean global NRS pain decreased in both groups and there was also a R.O.M. improvement. These results show that the intra-articular administration of nucleotides in subjects with both severe knee arthritis and chondropathy can be recommended since is able to reverse in the short and medium term symptoms and function with a significant improvement in quality of life

Treatment of lesions of the rotator cuff

: The impingement syndrome and tendinopathy of the rotator cuff are the most common causes (complaints) of pain and disability of the shoulder. The aim of this study is to evaluate the efficacy of a specific rehabilitative protocol, integrated with the administration of a nutritional supplement, in the conservative rehabilitative treatment, as well as in post-surgery, of patients with lesions of the rotator cuff. Two groups with syndrome of the rotator cuff were formed to follow different therapeutic courses, in relation to the choice of each subject to undergo the conservative treatment (Arm A) or the surgical one (Arm B). In Arm A the study included the association of therapy with ESWT (shock waves) with the proprioceptive Multi Joint System, for rehabilitating joint movement and muscle strength of the shoulder, and a specific nutritional supplement to reduce the pain and conserve the cartilage tissue. Between February 2009 and June 2009, we enrolled 30 subjects (randomized into three homogenous groups A1, A2, A3), average age 45±10 years, with rotator cuff syndrome with calcification of the shoulder, diagnosed through clinical examination and investigative instruments (X-ray, echography or NMR). In Arm B, from September 2009 to January 2010, we enrolled 50 patients (randomized into two groups, B1 and B2), 24 male (average age 58.4: min 28 and max 78) and 26 females (average age 59.5: min 30 and max 80), who had undergone rotator cuff operations and acromionplasty for non-massive lesions without important gleno-humeral instability, with either open or arthroscopic procedures. The analysis of the results of Arm A highlights that in terms of reducing pain the main benefits were found in Group A1 where the supplement was given. From the analysis of the data of Arm B, in both groups an improvement of the first 4 items evaluated was evident. In Group B1, 84 percent of the patients declared to be satisfied and improved and 16 percent were dissatisfied; in Group B2, where the nutritional supplement was given, 92 percent were satisfied and 8 percent were dissatisfied. In conclusion, we retain that in cases of rotator cuff syndrome, an integrated rehabilitative approach, whether conservative or post-surgical, directed at taking total control of the patient, must observe particular attention to the optimization of the articular tissular metabolic balance in order to favour better functional recovery