Equivalence relations and operators on ordered algebraic structures with difference.

This work concerns algebraic models of fuzzy and many-valued propositional logics, in particular Boolean Algebras, Heyting algebras, GBL-algebras and their dual structures, and partial algebras. The central idea is the representation of complex structures through simpler structures and equivalence relations on them: in order to achieve this, a structure is often considered under two points of view, as total algebra and partial algebra. The equivalence relations which allow the representation are congruences of partial algebras. The first chapter introduces D-posets, the partial algebraic structures used for this representation, which generalize Boolean algebras and MV-algebras. The second chapter is a study of congruences on D-posets and the structure of the quotients, in particular for congruences induced by some kinds of idempotent operators, here called S-operators. The case of Boolean algebras and MV-algebras is studied more in detail. The third chapter introduces GBL-algebras and their dual, and shows how the interplay of an S-operator with a closure operator gives rise to a dual GBL-algebra. Other results about the representation of finite GBL-algebras and GBL*algebras (GBL-algebras with monoidal sum), part of two papers previously published, are summarized and put in relation with the other results of this work

Making simple proofs simpler

An open partition \pi{} [Cod09a, Cod09b] of a tree T is a partition of the vertices of T with the property that, for each block B of \pi, the upset of B is a union of blocks of \pi. This paper deals with the number, NP(n), of open partitions of the tree, V_n, made of two chains with n points each, that share the root

Periapical healing after simplified endodontic treatments: A digital subtraction radiography study

Abstract Aim To evaluate the 6-month outcome of endodontic treatment of periapical lesions with integrated systems by clinical examination and digital subtraction radiography (DSR). Methodology Eighty-four patients with chronic periapical pathosis were randomly allocated to two groups and received endodontic treatment with Revo-S/One Step Obturator (G1, n = 41) or GTX/GTX Obturator (G2, n = 43). Six months later, clinical examination and DSR analysis were performed. Non-parametric statistical methods were used (p Results Total healing, partial healing and failure occurred in 48.4%, 48.4% and 3.2% of cases in G1, in 50.0%, 43.8% and 6.2% of cases in G2, respectively. No significant difference was detected. Conclusions The integrated endodontic techniques allowed for a high 6-month success rate in both groups in accordance with literature data

The Endless Saga of Monocyte Diversity

Cancer immunotherapy relies on either restoring or activating the function of adaptive immune cells, mainly CD8(+) T lymphocytes. Despite impressive clinical success, cancer immunotherapy remains ineffective in many patients due to the establishment of tumor resistance, largely dependent on the nature of tumor microenvironment. There are several cellular and molecular mechanisms at play, and the goal is to identify those that are clinically significant. Among the hematopoietic-derived cells, monocytes are endowed with high plasticity, responsible for their pro- and anti-tumoral function. Indeed, monocytes are involved in several cancer-associated processes such as immune-tolerance, metastatic spread, neoangiogenesis, and chemotherapy resistance; on the other hand, by presenting cancer-associated antigens, they can also promote and sustain anti-tumoral T cell response. Recently, by high throughput technologies, new findings have revealed previously underappreciated, profound transcriptional, epigenetic, and metabolic differences among monocyte subsets, which complement and expand our knowledge on the monocyte ontogeny, recruitment during steady state, and emergency hematopoiesis, as seen in cancer. The subdivision into discrete monocytes subsets, both in mice and humans, appears an oversimplification, whereas continuum subsets development is best for depicting the real condition. In this review, we examine the evidences sustaining the existence of a monocyte heterogeneity along with functional activities, at the primary tumor and at the metastatic niche. In particular, we describe how tumor-derived soluble factors and cell-cell contact reprogram monocyte function. Finally, we point out the role of monocytes in preparing and shaping the metastatic niche and describe relevant targetable molecules altering monocyte activities. We think that exploiting monocyte complexity can help identifying key pathways important for the treatment of cancer and several conditions where these cells are involved

Efficacy of three different irrigation techniques in the removal of smear layer and organic debris from root canal wall: A scanning electron microscope study

Abstract Aim Aim of this study was to compare the removal of smear layer and organic debris within the tooth canal among conventional needle irrigation, EndoVac and Endoactivator. Methodology Eighty single-rooted extracted human teeth were prepared with rotary NiTi instrumentation and randomly separated into 4 groups. Twenty teeth were used as positive control (Group 1), irrigated with only saline. Teeth assigned to Group 2 ( n = 20) received irrigation with a conventional syringe and a 30-gauge needle (NaviTip, Ultradent, South Jordan, UT); samples in Group 3 ( n = 20) were rinsed with an irrigation device based on apical negative pressure (EndoVac, Discus Dental, Culver City, CA) and teeth in Group 4 ( n = 20) were treated with a sonic irrigation system (EndoActivator, Dentsply Tulsa Dental, Tulsa, OK, USA). The amount of residual smear layer and debris was evaluated under a scanning electron microscope, and a semi-quantitative score was assigned to each root at the coronal, middle and apical thirds; the chi-square test was used to compare the results of the S.E.M. analysis. Results EndoActivator performed the best cleansing for both smear layer and organic debris in all root canal thirds, followed by EndoVac and conventional irrigation ( p > 0.001). EndoVac and conventional irrigation showed better cleaning in the coronal area, whereas EndoActivator performed an homogeneous cleansing at all levels. Conclusions The EndoVac system and the EndoActivator system demonstrated significantly more efficacy in cleansing root canal walls than conventional needle irrigation

A Small Chaperone Improves Folding and Routing of Rhodopsin Mutants Linked to Inherited Blindness

The autosomal dominant form of retinitis pigmentosa (adRP) is a blindness-causing conformational disease largely linked to mutations of rhodopsin. Molecular simulations coupled to the graph-based protein structure network (PSN) analysis and in vitro experiments were conducted to determine the effects of 33 adRP rhodopsin mutations on the structure and routing of the opsin protein. The integration of atomic and subcellular levels of analysis was accomplished by the linear correlation between indices of mutational impairment in structure network and in routing. The graph-based index of structural perturbation served also to divide the mutants in four clusters, consistent with their differences in subcellular localization and responses to 9-cis retinal. The stability core of opsin inferred from PSN analysis was targeted by virtual screening of over 300,000 anionic compounds leading to the discovery of a reversible orthosteric inhibitor of retinal binding more effective than retinal in improving routing of three adRP mutants

Boosting antitumor responses of T lymphocytes infiltrating human prostate cancers

Immunotherapy may provide valid alternative therapy for patients with hormone-refractory metastatic prostate cancer. However, if the tumor environment exerts a suppressive action on antigen-specific tumor-infiltrating lymphocytes (TIL), immunotherapy will achieve little, if any, success. In this study, we analyzed the modulation of TIL responses by the tumor environment using collagen gel matrix–supported organ cultures of human prostate carcinomas. Our results indicate that human prostatic adenocarcinomas are infiltrated by terminally differentiated cytotoxic T lymphocytes that are, however, in an unresponsive status. We demonstrate the presence of high levels of nitrotyrosines in prostatic TIL, suggesting a local production of peroxynitrites. By inhibiting the activity of arginase and nitric oxide synthase, key enzymes of L-arginine metabolism that are highly expressed in malignant but not in normal prostates, reduced tyrosine nitration and restoration of TIL responsiveness to tumor were achieved. The metabolic control exerted by the tumor on TIL function was confirmed in a transgenic mouse prostate model, which exhibits similarities with human prostate cancer. These results identify a novel and dominant mechanism by which cancers induce immunosuppression in situ and suggest novel strategies for tumor immunotherapy

Trattamenti endodontici semplificati di lesioni periapicali: valutazione del risultato clinico con Digital Subtraction Radiography

RiassuntoObiettiviValutare la guarigione di lesioni periapicali dopo sei mesi dal trattamento con sistemi integrati di strumentazione e otturazione canalare.Materiali e metodiSessanta pazienti con lesione periapicale sono stati assegnati a gruppi di trattamento (n=30) con sistema RevoS+One Step Obturator (G1) o con GTX+GTX Obturator (G2). La guarigione è stata valutata a sei mesi clinicamente e con Digital Subtraction Radiography (test non parametrici, p0,05).ConclusioniIl successo a sei mesi è alto e in linea coi dati della letteratura. Le tecniche semplificate considerate sono efficaci nel trattamento di lesioni periapicali.SummaryAimTo assess the healing of periapical lesions six months after the treatment with integrated systems for root canal shaping and filling.MethodologySixty patients with periapical lesion were randomly assigned to two treatment groups (n=30) with RevoS+One Step Obturator (G1) or GTX+GTX Obturator (G2). Healing was assessed by clinical examination and Digital Subtraction Radiography after six months (non-parametric tests, p0.05).ConclusionsThe six-month success was high and consistent with previously reported findings. The considered simplified techniques are effective for the treatment of periapical lesions