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Built on neurodegenerative lesions models, the disrupted motor grounding hypothesis (DMGH) posits that motor-system alterations selectively impair action comprehension. However, major doubts remain concerning the dissociability, neural signatures, and etiological generalizability of such deficits. Few studies have compared action-concept outcomes between disorders affecting and sparing motor circuitry, and none has examined their multimodal network predictors via data-driven approaches. Here, we first assessed action- and object-concept processing in patients with frontal lobe epilepsy (FLE), patients with posterior cortex epilepsy (PCE), and healthy controls. Then, we examined structural and functional network signatures via diffusion tensor imaging and resting-state connectivity measures. Finally, we used these measures to predict behavioral performance with an XGBoost machine learning regression algorithm. Relative to controls, FLE (but not PCE) patients exhibited selective action-concept deficits together with structural and functional abnormalities along motor networks. The XGBoost model reached a significantly large effect size only for action-concept outcomes in FLE, mainly predicted by structural (cortico-spinal tract, anterior thalamic radiation, uncinate fasciculus) and functional (M1-parietal/supramarginal connectivity) motor networks. These results extend the DMGH, suggesting that action-concept deficits are dissociable markers of frontal/motor (relative to posterior) disruptions, directly related to the structural and functional integrity of motor networks, and traceable beyond canonical movement disorders., Competing Interests: Declaration of competing interest None to declare., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The pressing call to detect sensitive cognitive markers of frontal lobe epilepsy (FLE) remains poorly addressed. Standard frameworks prove nosologically unspecific (as they reveal deficits that also emerge across other epilepsy subtypes), possess low ecological validity, and are rarely supported by multimodal neuroimaging assessments. To bridge these gaps, we examined naturalistic action and non-action text comprehension, combined with structural and functional connectivity measures, in 19 FLE patients, 19 healthy controls, and 20 posterior cortex epilepsy (PCE) patients. Our analyses integrated inferential statistics and data-driven machine-learning classifiers. FLE patients were selectively and specifically impaired in action comprehension, irrespective of their neuropsychological profile. These deficits selectively and specifically correlated with (a) reduced integrity of the anterior thalamic radiation, a subcortical structure underlying motoric and action-language processing as well as epileptic seizure spread in this subtype; and (b) hypoconnectivity between the primary motor cortex and the left-parietal/supramarginal regions, two putative substrates of action-language comprehension. Moreover, machine-learning classifiers based on the above neurocognitive measures yielded 75% accuracy rates in discriminating individual FLE patients from both controls and PCE patients. Briefly, action-text assessments, combined with structural and functional connectivity measures, seem to capture ecological cognitive deficits that are specific to FLE, opening new avenues for discriminatory characterizations among epilepsy types., Competing Interests: Declaration of Competing Interest None of the authors has any conflict of interest to disclose., (Copyright © 2021. Published by Elsevier Inc.)

The paper discusses the major Argentineans contributors, medical physicists and scientists, in medical imaging and the development of medical imaging in Argentina. The following are presented: history of medical imaging in Argentina: the pioneers; medical imaging and medical revolution; nuclear medicine imaging; ultrasound imaging; and mathematics, physics, and electronics in medical image research: a multidisciplinary endeavor.

The purpose of this investigation was to study basal cerebral glucose absorption patterns associated to long-term post-traumatic stress disorder. Fluorodeoxyglucose positron emission tomography (FDG-PET) and statistic parametric mapping (SPM) were used to compare regional cerebral glucose absorption between 15 war veterans (Hispanic men, aged 39-41 (M = 39.5, SD = 0.84)) diagnosed with post-traumatic stress disorder (PTSD) based on DSM-IV criteria, and a matching control group of six asymptomatic veterans. This study was conducted 20 years after the traumatic events. PTSD patients presented relatively diminished activity (P<0.005) in: cingulate gyri, precuneus, insula, hippocampus; frontal, pre-frontal and post-central regions; lingual, calcarine, occipital medial and superior gyri, and verbal and paraverbal areas. Relativeley augmented activity (P<0.005) was observed in PTSD patients in: fusiform, temporal superior, medial, and inferior gyri; occipital medial, inferior and lingual gyri; precuneus, and cerebellum. The amygdala and the thalamus showed normal metabolic activity. Various brain regions that showed diminished activity (limbic, frontal and prefrontal cortex, multimodal parieto-occipital areas and verbal and paraverbal areas) have evolved lately, and sub-serve highly complex cognitive and behavioural functions. Metabolic activity patterns are comparable to those observed in personality disorders of the borderline type.

Spontaneous rupture of gastrointestinal stromal tumor (GIST) with hemoperitoneum is an extremely rare clinical presentation of this mesenchymal tumor. We report the unusual case of a 68-year-old man who was admitted to the hospital with abdominal pain. While waiting for the results of his laboratory tests the patient became pale and tachycardic and his abdomen distended with generalized rebound tenderness. A CT scan suggested rupture of a cavernous angioma of the liver and the patient was brought to the operating room for an explorative laparoscopy, which revealed hemoperitoneum from a ruptured giant gastric GIST. After conversion to laparotomy, the tumor was excised: it was 11 x 10 x 5 cm in size, with massive necrosis and clotted blood inside. Immunohistochemical examination revealed reactivity to c-KIT and CD34, consistent with the diagnostic criteria for GIST, with low mitotic activity (< 5/50 HPF). The postoperative course was uneventful, and the clinical and radiological follow-up at 6 months is negative for recurrence.

Schizophrenia has been characterized as a complex disease, in which various cerebral regions may be affected. The purpose of this study was to compare the cerebral regions that are involved in mild and severe negative symptoms, and to determine whether the degree of severity can be related to specific dysfunctional areas of the brain. The PANS Scale was used to form two groups of patients with prevalence of negative symptoms: Mildly Affected (MA), and Severely Affected (SA). Brain PETs were obtained in resting conditions, and SPM (Statistical Parametric Mapping) was used to perform statistical comparisons. The MA-group showed increased activity in: posterior cingulate gyrus, middle frontal gyrus, precentral gyrus, middle occipital gyrus, cuneus and post-central gyrus; decreased activity in inferior frontal gyrus, orbitofrontal and fusiform gyrus. The SA-group showed increased activity in: globus pallidus, insular cortex, cuneus, claustrum, post-central gyrus and pre-central gyrus; decreased activity in fusiform gyrus and superior temporal gyri. These results permit correlation of negative symptomatology with abnormalities in the cortico-striato-pallido-thalamic neural circuit. Severity of negative symptoms is clearly correlated to abnormal left external pallidal activation, evidencing the relevance of this nucleus for cognitive, planning and social capabilities. Specific therapeutic strategies might be derived from pallidal neurotransmitter systems studies. Key words: schizophrenia, negative symptoms, severity, PET, globus pallidus, claustrum.

Background: Breast reconstruction after a mastectomy, today is considered the best choice to improve the quality of life for the patient. The aim of the procedure is to consider the aesthetic results obtained and the various involvements, comparing them with those already reported in literature. METHODS. There is no certain data of the number of breast reconstructions performed in Italy in the few years. In 1999, in Veneto, reconstruction surgery after total breast removal, represented only 16% of the operations. In our surgery Division, from 1996 to 2000, there were breast reconstructions performed, either immediately or delayed on 87 patients out of 118 after mastectomy. 73.7% none over the age of 60 (range 27-60). The breast removal technique used is the Madden, while, for the reconstruction we have put into effect the submuscle prosthetic implant; 63 patients were subject to follow-up treatment during the period of 10 to 36 months., Results: Seventy-eight percent of the women have judged the final aesthetic results the same or better than expected. Based on reconstruction with prosthesis, is the preferred procedure, even with serious complications which do not always influence the final results. This preference is because of the reduced operation time and the psychological and physical benefits due to immediate restoral of the mammary volume and shape., Conclusions: Some problems (Garavaglia Law) have slowed down the diffusion in Italy of this type of treatment which is now receiving more and more request and approval by the women affected with breast cancer.

Despite the increasing use of diagnostic workstations, film reading is still commonplace in most radiology departments all over the world. The purpose of this work is to assess the adoption of image review workstations in a radiology department where the usual primary diagnosis is film-based and cannot be replaced with diagnostic workstations. At our institution, a tertiary care center specialized in diagnostic imaging, a pair of PC-based review workstations running a Digital Imaging and Communications in Medicine (DICOM)-conformant public domain software for image display and analysis were installed in two reading rooms. Studies are automatically routed after acquisition from the picture archiving and communication system (PACS) server to the workstations and remain available for visualization for approximately 15 to 20 days. Data from two radiologists and two technologists collected over a 3-month period were analyzed, including purpose of use, time savings as compared to traditional manual methods, and overall user satisfaction. The results from the analysis presented in this work indicate a high degree of approval from the users, who report significant timesavings in numerous circumstances, in particular when it comes to discussing findings with referring physicians whenever films are not available. It also enriches communication between radiologists, facilitating peer review on the telephone when one of them has questions at the outcome of any given study. One of the main advantages associated with the system is the possibility of using it as a powerful tool for teaching and research. In conclusion, even when primary diagnosis is performed on film, the availability of a PACS for review can be helpful to enhance communication with referring physicians, as well as technologists and radiologists' efficiency. Our experience shows that it is possible to implement such a system using low-cost or freely available components without compromising ease of use while keeping costs down, which is a major concern in developing countries.

The success of the 15O-water PET technique to localize statistically significant changes in regional cerebral blood flow is dependent on factors such as the activity level injected and the magnitude of the flow change. Undetectable changes may occur if insufficient activity is injected leading to high levels of statistical noise or the task performed results in only small changes in blood flow. To explore the relationship between injected activity and statistical significance, we performed a series of studies with the ECAT EXACT HR+, a high resolution PET tomograph. A parametric verbal working memory task (the N-back task) was selected to examine the relationship between regional cerebral blood flow and working memory load across a range of injected doses of 15O-water. At each activity level the volunteers were required to perform four different levels of the N-back task, a task in which a letter displayed on a monitor is matched with the letter displayed N letters previously. With increasing N, this task places increased load on working memory. For this study, 5, 10, and 15 mCi of 15O-water were injected into nine normal volunteers. The complete sequence of four tasks (N = 0, 1, 2, and 3) at three activity levels was repeated twice, for a total of 24 injections of 15O-water. We show that the peak count rate performance for the HR+ is approached at injected activity levels of 15O-water around 15 mCi. For this particular choice of N-back task, robust activation maps can nevertheless be obtained with as little as 5 mCi injected dose., (Copyright 1999 Academic Press.)