Risks and limits of bariatric surgery: old solutions and a new potential option.

The present review focuses on the side effects that ex-obese patients face following bariatric surgery. We searched through the principal medical indexes (SCOPUS, Web of Science, PubMed, MEDLINE) using the following words, both alone and in combinations: bariatrics; bariatric surgery; anemia; vitamin B12; cobalamin; folate; folic acid; iron; iron supplements; gut microbiota; lactalbumin; α-lactalbumin. To perform exhaustive research, we considered articles published since 1985. Bariatric surgery induces states of nutritional deficiencies. In particular, the surgery results in a drastic fall in the levels of iron, cobalamin, and folate. Despite the dietary supplements which can counteract such decrease, some limitations exist in the nutraceutical approach. Indeed, the gastrointestinal side effects of supplements, the alterations in the microbiota, and the reduced absorption induced by the surgery may impair the effect of dietary supplements, exposing the patients to the risk of developing nutritional deficiencies. Recent literature reports the effect of promising molecules to counteract such limitations, which include α-lactalbumin, a whey protein with prebiotic activities, and new pharmaceutical forms of iron supplements, namely micronized ferric pyrophosphate. If on the one hand, α-lactalbumin enhances intestinal absorption and helps in restoring a physiological microbiota, micronized ferric pyrophosphate has a high tolerability and low or null risk of gastrointestinal side effects. Bariatric surgery represents a valid solution to obesity and obesity-related disease. However, the procedure may induce deficiencies in micronutrients. Data exists on the promising activities of α-lactalbumin and micronized ferric pyrophosphate, which may help in preventing bariatric-induced anemia.

Influence of stimulus color on the control of reaching-grasping movements.

This kinematic study aimed to determine whether color is a stimulus property involved in the control of reaching-grasping movements. Subjects reached and grasped a target-object, located either on the right or on the left of the subject's midline. A distractor, placed along the subject's midline, could be randomly presented. The colors, i.e., both chromaticity (red and green stimuli were presented) and lightness, of the target and distractor were varied in experiment 1. Only stimulus lightness and only stimulus chromaticity were varied in experiments 2 and 3, respectively. In experiment 4 subjects matched with their thumb and index finger the size of the target-stimuli presented in experiment 1. Chromaticity (experiments 1 and 3) of the target and distractor influenced grasp, but not reach. Maximal finger aperture was larger during grasping the red than the green target. Data collected in the matching task (experiment 4) confirmed a trend to overestimate the red target and to underestimate the green one. During grasp, hand shaping was influenced by distractor chromaticity when it was different from target chromaticity. Distractor lightness affected reach, but not grasp (experiments 1 and 2). Reach was slower when the distractor was lighter and arm trajectory veered away from it. The results of the present study suggest that color, that is the ensemble of chromaticity and lightness, is a stimulus property involved in the control of reaching-grasping. The different effects of target color on reach and grasp support the notion that intrinsic object properties, such as color, affect grasp more than reach. In addition, the different effects of distractor chromaticity and lightness on reach and grasp confirm that target-objects are visually extracted from surrounding cues by means of different processes, according to the required motor response.

Visual illusions and the control of children arm movements.

The aim of the present study was to determine whether children like adults (Gentilucci M, Chieffi S, Daprati E, Saetti MC, Toni I. Visual illusion and action. Neuropsychologia 1996;34:369-76; Gentilucci M, Daprati E, Gangitano M, Toni I. Eye position tunes the contribution of allocentric and egocentric information to target localisation in human goal directed arm movements. Neurosci Lett 1997;222:123-6) are influenced by visual illusions when they transform visual information in motor command. Children and adults pointed to a shaft extremity of the Müller-Lyer configurations, as well as to an extremity of a control configuration. Movements were executed in two experimental conditions. In the vision condition subjects saw both the stimulus and their hand before and during movement. In the no vision (memory) condition subjects saw the stimulus and their hand before, but not during movement. Movement started 5 s after vision was precluded. The Müller-Lyer illusion affected pointing kinematics of both children and adults. As found previously (Gentilucci M, Chieffi S, Daprati E, Saetti MC, Toni I. Visual illusion and action. Neuropsychologia 1996;34:369-76; Gentilucci M, Daprati E, Gangitano M, Toni I. Eye position tunes the contribution of allocentric and egocentric information to target localisation in human goal directed arm movements. Neurosci Lett 1997;222:123-6), subjects undershot and overshot the shaft extremity of the closed and of the open configuration, respectively. The illusion effect was greater in the no vision than in the vision condition. These results show that in children like in adults the system underlying visual perception in an object-centered frame of reference and that involved in motor control functionally interact with each other. Although the processes of target localisation were the same, the transformation of target position information in a sequence of motor patterns was different in children from that in adults. Even if both children and adults lengthened duration of the deceleration phase in the vision condition, only adults shortened duration of the acceleration phase in order to maintain constant movement time (Viviani P, Schneider R. A developmental study of the relationship between geometry and kinematics in drawing movements. J Exp Psychol 1991;17:198-218). This result suggests that children are yet unable to co-ordinate temporally acceleration with deceleration phase.

Language and motor control.

We investigated the possible influence of automatic word reading on processes of visuo-motor transformation. Subjects reached and grasped an object on which the following Italian words were printed: "VICINO" (near) or "LONTAN" (far) on an object either near or far from the agent (experiments 1, 2); PICCOLO (small) or "GRANDE" (large) on either a small or a large object (experiment 4); and "ALTO" (high) or "BASSO" (low) on either a high or a low object (experiment 5). The kinematics of the initial phase of reaching-grasping was affected by the meaning of the printed words. Namely, subjects automatically associated the meaning of the word with the corresponding property of the object and activated a reach and/or a grasp motor program influenced by the word. No effect on initial reach kinematics was observed for words related to object properties not directly involved in reach control (experiment 3). Moreover, in all the experiments, the presented words poorly influenced perceptual judgement of object properties. In experiments 5-7, the effects of the Italian adjectives "ALTO" (high) and "BASSO" (low) on reaching-grasping control were compared with those of the Italian adverbs "SOPRA" (up) and "SOTTO" (down). Adjectives influenced visual analysis of target-object properties, whereas adverbs more directly influenced the control of the action. We suggest that these effects resemble the structure of a sentence, where adjectives are commonly referred to nouns, and adverbs to verbs. In other words, class of words and, in a broad sense, grammar influenced motor control. The results of the present study show that cognitive functions such as language can affect visuo-motor transformation. They are discussed according to the notion that a strict relation between language and motor control exists, and that the frontal cortex can be involved in interactions between automatic word reading and visuo-motor transformation.

Impaired control of an action after supplementary motor area lesion: a case study.

The kinematics of the action formed by reaching-grasping an object and placing it on a second target was studied in a patient who suffered from an acute vascular left brain lesion, which affected the Supplementary Motor Area proper (SMA-proper) (Matelli M, Luppino G. Thalamic input to mesial and superior area 6 in the macaque monkey. Journal of Comparative Neurology 1996;372:59-87, Matelli M, Luppino G, Fogassi L, Rizzolatti G. Thalamic input to inferior area 6 and area 4 in the macaque monkey. Journal of Comparative Neurology 1989;280:468-488), and in five healthy control subjects. The reach kinematics of the controls was affected by the positions of both the reaching-grasping and the placing targets (Gentilucci M, Negrotti A, Gangitano M. Planning an action. Experimental Brain Research 1997;115:116-28). In contrast, the reach kinematics of the patient was affected only by the position of the reaching-grasping target. By comparing these results with those previously found in Parkinson's disease patients executing the same action (Gentilucci M, Negrotti A. Planning and executing an action in Parkinson's disease patients. Movement Disorders 1999;1:69-79, Gentilucci M, Negrotti A. The control of an action in Parkinson's disease. Experimental Brain Research 1999;129:269-277), we suggest that the anatomical "motor" circuit formed by SMA-proper (see above), Basal Ganglia (BG) and Thalamus (Alexander GE, Crutcher MD. Functional architecture of basal ganglia circuits: neural substrates of parallel processing. Trends in the Neurosciences 1990;13:266-271, Hoover JE, Strick PL. Multiple output channels in the basal ganglia. Nature 1993;259:819-821) may be involved in the control of actions: SMA-proper assembles the sequence of the action, whereas BG updates its parameters and stores them.

Verbal learning strategies in patients with multiple sclerosis.

Word list learning was studied in patients with a definite diagnosis of Multiple Sclerosis and in Normal Control subjects by means of the selective reminding procedure of Buschke and Fuld in two learning conditions: (1) using unrelated items and (2) paired-associate items. The Multiple Sclerosis patients displayed poor learning in both conditions. To identify the functional locus of their deficit, stochastic Markov chain analyses were performed, which allowed individual measurements of encoding, automatic and intentional retrieval abilities. On both tasks, encoding on the first trial and automatic retrieval on the subsequent trials were impaired in Multiple Sclerosis patients, whereas intentional retrieval, both with and without reminding by the examiner, appeared to be preserved. As all of the impaired abilities require a normal speed of information processing, the salient learning deficit of the Multiple Sclerosis patients could be tentatively traced back to the slowing down of their mental activity.

Recognising a hand by grasp.

The present study aimed to demonstrate that motor representations are used to recognise biological stimuli. In three experiments subjects were required to judge laterality of hands and forearms presented by pictures. The postures of the hands were those assumed when holding a small, medium and large sphere. In experiment 1, the sphere held in hand was presented, whereas in experiment 2 it was absent. In experiment 3, the same images, showing holding-a-sphere hands, as in experiment 1 were presented, but without forearm. In all experiments one finger of each hand could be absent. In experiment 1 recognition time was longer for those hand postures for which the corresponding grasping motor acts required more accuracy. This was confirmed by a control experiment (experiment 4), in which subjects actually grasped the spheres. Absence of fingers did not influence right-left hand recognition. However, the absence of target object in experiment 2, and of forearm in experiment 3 reduced the effects of the type of holding on hand laterality recognition. The results of the present study indicate that grasp representations are used to recognise hand laterality. In particular, the visual description of how hand and object interact in space (the opposition space [M.A. Arbib, Programs, schemas and neural networks for control of hand movement: beyond the RS frameworks, in: M. Jeannerod (Ed.), Attention and Performance XIII: Motor Representation and Control, Lawrence Erlbaum, Hillsdale, NJ, 1990, 111-138; M.A. Arbib, T. Iberall, D. Lyons, Coordinated control programs for movements of the hand, in: A.W. Goodman, I. Darian-Smith (Eds.), Hand function and the neocortex, Springer, Berlin, 1985, pp. 135-170]) and the anchoring of the hand to the agent are the features of the grasp representations used in hand-recognition processes. The data are discussed according to the more general notion that motor representations are automatically extracted in the process of intuiting situations, or people's intentions. These motor representations, which are compared with those of other people, contain concrete information on the actions (the motor program) by which a situation is created and on the aim of the agents executing those actions.

[Prevalence of changes in performance, subjective symptoms and occupational dermatitis before and after carrying out improvements in the surgical block of the Modena Polyclinic]. / Prevalenza di alterazioni delle performances, sintomi soggettivi e dermopatie professionali prima e dopo interventi di bonifica di un blocco operatorio del Policlinico di Modena.

The Preventive Medicine Unit for Personnel in the USL N. 16 of Modena has conducted a study to evaluate the prevalence of subjective symptoms and professional dermatitis among nurses working in a general surgery operating theatre of the Modena "Policlinico" Hospital (36 and 41 employees were studied respectively in 1990 and 1991), before and after the installation of gas evacuators and a modification in the use of detergent and disinfectant substances. The study demonstrates that installation of gas evacuating systems, if not supported by an intervention of air-conditioning plant, does not sufficiently reduce alterations in subjective symptoms. On the other hand, the modifications in the use of detergent and disinfectants has demonstrated a favourable reduction in the prevalence of professional dermatitis (from 43% to 18%; chi2 = 4.35, p = 0.037).

[Urinary measurement of D-glucaric acid in operating room personnel in the Modena USL 16 hospitals]. / Dosaggio urinario di acido D-glucarico nel personale di sala operatoria degli ospedali dell'USL 16 di Modena.

The Authors describe the results of a research conducted in order to evaluate the amount of D-glucaric acid in the urine of 131 operating theatre workers exposed to anesthetic gases and in a control group of 25 non-exposed hospital personnel. The comparison of the results of the two groups points out a significant difference (in the exposed members 60.7 +/- 2.4 mumol/1 to 46.7 +/- 4.3 mumol/l [+/- s.e.] in the control group; t-test: p = 0.016). The research also considered the influence of certain variables such as age, sex, smoking, alcohol, drug use and liver disorders. None of these variables has proven to be of significant influence on the D-glucaric acid urinary concentration.