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Background: Food addiction (FA) is characterised by the consumption of appetible foods and by addictive psychological and behavioural symptoms such as cravings, tolerance, limited control of substance intake and withdrawal symptoms. Despite previous research on FA has been hindered by the lack of a formal definition for this condition, recent global trends have stirred the interest of the scientific community towards a proper classification and construct of FA. More specifically, recent studies have pointed towards shared defective neurobiological mechanisms as well as frequent comorbidities between FA, eating disorders, mood disorders, anxiety disorders and substance-related and addictive disorders., Objective: In this review, we will provide an overview of the complex symptomatology of food addiction evaluating its relationship with mood disorders, anxiety disorders, eating disorders and substance-related and addictive disorders., Methods: We wrote a systematic review and followed a PRISMA methods., Results: Patients with FA and substance use disorders show similar risk factors, neurobiological and hormonal correlates, personality traits and symptom profiles. The presence of FA appears to be directly proportional to the burden of symptoms of affective disorder. The comorbidity between FA and other eating disorders is associated with worse clinical conditions and symptoms., Conclusion: FA should be considered a sort of transnosological construct existing in different psychopathological domains that have similarities with substance-related, affective, and eating disorders. Furthermore, FA seems to be likely an important factor related to several psychopathological dimensions, but further studies are needed to clarify this view., Level of Evidence: Level V, review article.

Dual-process models with a default-interventionist architecture explain early emotional action tendencies by a stimulus-driven process, and they allow goal-directed processes to intervene only in a later stage. An alternative dual-process model with a parallel-competitive architecture developed by Moors, Boddez, and De Houwer (Emotion Review, 9(4), 310-318, 2017), in contrast, explains early emotional action tendencies by a goal-directed process. This model proposes that stimulus-driven and goal-directed processes often operate in parallel and compete with each other, and that if they do compete, the goal-directed process often wins the competition. To examine these predictions, we set up a goal-directed process in an experimental group by rewarding participants for avoiding positive stimuli and for approaching negative stimuli and punishing them for the opposite behavior. We expected this process to compete with a potentially preexisting stimulus-driven process in which positive stimuli are associated with approach and negative stimuli with avoidance. We compared the elicited action tendencies of participants in this group with a control group in which only the stimulus-driven process could operate. Early approach and avoidance tendencies were assessed via motor evoked potentials (MEP) measured in the finger muscles previously trained to approach or to avoid stimuli after single-pulse transcranial magnetic stimulation (TMS) delivered at 400 ms. Results confirmed that positive/negative stimuli led to stronger avoidance/approach tendencies in the experimental group but not to approach/avoidance tendencies in the control group. This suggests that goal-directed processes are indeed able to determine relatively early emotional action tendencies, but it does not show that goal-directed process can defeat stimulus-driven processes.

5'-Nucleotidase is involved in sperm capacitation via the cAMP-adenosine pathway and in sperm motility via direct adenosine production from AMP. Since these functions are reduced in varicocele, the aim of this study was to investigate whether the enzyme levels were altered in sperm from varicocele patients. The mean (SD) international units (IU) of 5'-nucleotidase activity in seminal plasma from 35 varicocele III patients was 0.16(0.09) IU ml(-1) vs 0.35(0.13) IU ml(-1) in 53 controls, this decrease being statistically significant at p < or = 0.001. A significant decrease in activity, expressed as international units per mg of protein concentration in spermatozoa homogenates, was also observed with spermatozoa: 0.0018(0.0017) IU mg(-1) in varicocele III vs 0.0081(0.0060) IU mg(-1) in controls, at p < or = 0.001. Compared to controls, the activity decrease observed both in spermatozoa and seminal plasma from 45 men with varicocele I was not statistically significant at p < or = 0.05. To determine the diagnostic value of 5'-nucleotidase in assessing sperm fertility in varicocele III, we used the likelihood ratios method and best cut-offs were identified in receiver operating characteristic curves. With a prevalence of 36%, the post-test probability of infertility was 91% in spermatozoa and 78% in seminal plasma. The cut-off values of 5'-nucleotidase activity discriminating for fertile/unfertile semen were 0.2 IU ml(-1) in seminal plasma and 0.003 IU mg(-1) of protein in spermatozoa. Overall, determination of 5'-nucleotidase activity, especially in spermatozoa, can be useful to characterize different varicocele degrees as well as the sperm fertility potential.

Two distinct classes of lipocalin isoforms (OBP-IIs and OBP-IIIs) were purified and identified from porcine nasal mucosa of male and female individuals. Using primers designed on their N-terminal sequence, the complete primary structures of the mature polypeptides were determined. Mass spectrometry analysis confirmed the identity of the cDNA-derived sequences and provided information regarding their post-translational modifications. These species strongly resemble a lipocalin expressed by von Ebner's gland and salivary lipocalins carrying sex-specific pheromones secreted only by the boar's submaxillary glands. Both OBP-IIs and OBP-IIIs present two cysteines paired in a disulphide bond; the remaining residues occur in a reduced form. In addition, OBP-IIIs are heavily glycosylated and markedly different in their glycan moiety from the salivary lipocalins. A three-dimensional model is proposed based on protein species with known structure. Like salivary lipocalins, OBP-IIIs bind a number of odorant molecules, with highest affinity for the specific pheromone 5alpha-androst-16-en-3-one. The high similarity between OBPs from the nasal area and lipocalins from secretory glands suggests a common function in binding the same pheromonal ligands, the latter carrying chemical messages into the environment the former delivering them to specific receptors.

Seminal plasma separated from freshly ejaculated bull semen contains vesicles with a 5'-nucleotidase activity incorporated as an ectoenzyme anchored by glycosyl phosphatidylinositol (GPI). After its extraction from bull seminal plasma vesicles, the protein was purified and reconstituted into hen egg yolk lecithin liposomes obtained through prolonged dialysis of buffered n-octylglucoside detergent solutions of lipid, protein and various effectors against detergent-free solutions. Gel filtration experiments showed that the enzyme incorporated into liposomes in a dimeric form with its two subunits linked by disulfide bridges. In the presence of reduced glutathione, the protein dissociated into monomers and failed to incorporate into liposomes. Electron spin resonance (ESR) experiments, performed with liposomes containing electron spin labels localized at the hydrophilic lipid headgroups (5-doxyl stearic acid) or in the hydrophobic lipid hydrocarbon chains (16-doxyl stearic acid), demonstrated that the incorporation of 5'-nucleotidase resulted in the immobilization of the spin probes. Furthermore, the spectral parameters obtained before and after treatment of 5'-nucleotidase-containing liposomes with phosphatidylinositol-specific phospholipase C (PI-PLC) indicated that the liposome membrane bilayer did not contain protein segments. This supports the well-known ecto-localization of 5'-nucleotidase and rules out a previously reported possibility of a proteic transmembrane anchoring of the enzyme.