217 research outputs found

    A Cross-Recurrence Analysis of the Pupil Size Fluctuations in Steady Scotopic Conditions

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    Pupil size fluctuations during stationary scotopic conditions may convey information about the cortical state activity at rest. An important link between neuronal network state modulation and pupil fluctuations is the cholinergic and noradrenergic neuromodulatory tone, which is active at cortical level and in the peripheral terminals of the autonomic nervous system (ANS). This work aimed at studying the low- and high-frequency coupled oscillators in the autonomic spectrum (0–0.45 Hz) which, reportedly, drive the spontaneous pupillary fluctuations. To assess the interaction between the oscillators, we focused on the patterns of their trajectories in the phase-space. Firstly, the frequency spectrum of the pupil signal was determined by empirical mode decomposition. Secondly, cross-recurrence quantification analysis was used to unfold the non-linear dynamics. The global and local patterns of recurrence of the trajectories were estimated by two parameters: determinism and entropy. An elliptic region in the entropy-determinism plane (95% prediction area) yielded health-related values of entropy and determinism. We hypothesize that the data points inside the ellipse would likely represent balanced activity in the ANS. Interestingly, the Epworth Sleepiness Scale scores scaled up along with the entropy and determinism parameters. Although other non-linear methods like Short Time Fourier Transform and wavelets are usually applied for analyzing the pupillary oscillations, they rely on strong assumptions like the stationarity of the signal or the a priori knowledge of the shape of the single basis wave. Instead, the cross-recurrence analysis of the non-linear dynamics of the pupil size oscillations is an adaptable diagnostic tool for identifying the different weight of the autonomic nervous system components in the modulation of pupil size changes at rest in non-luminance conditions

    Uterine Sarcomas: An Updated Overview Part 2: Endometrial Stromal Tumor

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    Uterine sarcomas (USs) account for 3–9% of uterine malignant neoplasia and about 5% of all gynaecologic malignancies. Despite their low prevalence, these tumors stimulate a great interest because of their aggressiveness, poor prognosis and high mortality rate. According to the last world health organization (WHO) classification and the International Federation of gynecology and obstetrics committee (FIGO) staging, USs are categorized as pure mesenchymal tumors (endometrial stromal sarcoma, leiomyosarcoma and undifferentiated uterine) and mixed tumors (carcinosarcoma and adenosarcoma). Due to their non-specific signs and symptoms, USs are commonly diagnosed in advanced stage, more often after surgery for a suspected leiomyoma. Although surgery followed by adjuvant therapies represent the common choices for USs, they show poor efficacy due to the early occurrence of metastasis, and the high resistance of tumors to radio-and chemotherapy. Presently, specific expression profiles and new cytotoxic agents are under investigation. In these reviews, we summarized clinical and pathological features, imaging characteristics, therapeutic approaches, genomic and molecular aberration associated with smooth muscle neoplasia (Part 1) and endometrial stromal neoplasia (Part 2); the goal is to understand the biology and the molecular signature of these tumors, in order to focus on their best management

    Facial Oedema Is Not Always Angioedema: A Case of Spontaneous Pneumomediastinum with Subcutaneous Emphysema during COPD Exacerbation

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    We report a case of acute facial oedema in an elderly hospitalized patient which was initially misdiagnosed as angioedema secondary to antibiotics in a patient with an allergic diathesis. We describe the differential aetiologies and then the true cause of the oedema, which was an uncommon complication of a very common condition in the elderly: a pneumomediastinum with subcutaneous emphysema probably due to rupture of an emphysematous lung bulla during chronic obstructive pulmonary disease (COPD) exacerbation. Lastly, we focus on the therapeutic procedures instituted for the treatment of the pneumomediastinum

    Uterine Sarcomas: An Updated Overview. Part 1: Smooth Muscle Tumors

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    Uterine sarcomas (USs) account for 3–9% of uterine malignant neoplasia and about 5% of all gynaecologic malignancies. Despite their low prevalence, these tumors stimulate a great interest because of their aggressiveness, poor prognosis and high mortality rate. According to the last World Health Organization (WHO) classification and the International Federation of Gynecology and Obstetrics Committee (FIGO) staging, USs are categorized as pure mesenchymal tumors (endometrial stromal sarcoma, leiomyosarcoma and undifferentiated uterine), and mixed tumors (carcinosarcoma and adenosarcoma). Due to their non-specific signs and symptoms, USs are commonly diagnosed in advanced stage, more often after surgery for a suspected leiomyoma. Although surgery followed by adjuvant therapies represent the common choices for USs, they show poor efficacy due to the early occurrence of metastasis, and the high resistance of tumors to radio-and chemotherapy. Presently, specific expression profiles and new cytotoxic agents are under investigation. In these reviews, we summarized clinical and pathological features, imaging characteristics, therapeutic approaches, genomic and molecular aberration associated with smooth muscle neoplasia (Part 1) and endometrial stromal neoplasia (Part 2); the goal is to understand the biology and the molecular signature of these tumors, in order to focus on their best management

    Double Attack to Oxidative Stress in Neurodegenerative Disorders: MAO-B and Nrf2 as Elected Targets

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    Oxidative stress and neuroinflammation play a pivotal role in triggering the neurodegenerative pathological cascades which characterize neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases. In search for potential efficient treatments for these pathologies, that are still considered unmet medical needs, we started from the promising properties of the antidiabetic drug pioglitazone, which has been repositioned as an MAO-B inhibitor, characterized by promising neuroprotective properties. Herein, with the aim to broaden its neuroprotective profile, we tried to enrich pioglitazone with direct and indirect antioxidant properties by hanging polyphenolic and electrophilic features that are able to trigger Nrf2 pathway and the resulting cytoprotective genes' transcription, as well as serve as radical scavengers. After a preliminary screening on MAO-B inhibitory properties, caffeic acid derivative 2 emerged as the best inhibitor for potency and selectivity over MAO-A, characterized by a reversible mechanism of inhibition. Furthermore, the same compound proved to activate Nrf2 pathway by potently increasing Nrf2 nuclear translocation and strongly reducing ROS content, both in physiological and stressed conditions. Although further biological investigations are required to fully clarify its neuroprotective properties, we were able to endow the pioglitazone scaffold with potent antioxidant properties, representing the starting point for potential future pioglitazone-based therapeutics for neurodegenerative disorders

    Characteristic eye movements in ataxia-telangiectasia-like disorder: An explanatory hypothesis

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    Objective: To investigate cerebellar dysfunctions and quantitatively characterize specific oculomotor changes in ataxia-telangiectasia-like disorder (ATLD), a rare autosomal recessive disease caused by mutations in the MRE11 gene. Additionally, to further elucidate the pathophysiology of cerebellar damage in the ataxia-telangiectasia (AT) spectrum disorders. Methods: Saccade dynamics, metrics, and visual fixation deficits were investigated in two Italian adult siblings with genetically confirmed ATLD. Visually guided saccades were compared with those of 40 healthy subjects. Steady fixation was tested in primary and eccentric positions. Quantitative characterization of saccade parameters, saccadic intrusions (SI), and nystagmus was performed. Results: Patients showed abnormally hypermetric and fast horizontal saccades to the left and greater inaccuracy than healthy subjects in all saccadic eye movements. Eye movement abnormalities included slow eye movements that preceded the initial saccade. Horizontal and vertical spontaneous jerk nystagmus, gaze-evoked, and rebound nystagmus were evident. Fixation was interrupted by large square-wave jerk SI and macrosaccadic oscillations. Conclusion: Slow eye movements accompanying saccades, SI, and cerebellar nystagmus are frequently seen in AT patients, additionally our ATLD patients showed the presence of fast and hypermetric saccades suggesting damage of granule cell-parallel fiber-Purkinje cell synapses of the cerebellar vermis. A dual pathogenetic mechanism involving neurodevelopmental and neurodegenerative changes is hypothesized to explain the peculiar phenotype of this disease

    Appendiceal goblet cell carcinoma has marginal advantages from perioperative chemotherapy: a population-based study with an entropy balancing analysis

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    PurposeThe aim is to clarify the use of perioperative chemotherapy in resectable goblet cell carcinoma (GCC).MethodsA retrospective study was carried out based on the Surveillance, Epidemiology, and End Results study. The population was divided: into patients who received only radical surgery (group A) and those who received radical surgery plus chemotherapy (group B). An entropy balancing was carried out to correct the imbalance between the two groups. Two models were generated. Model 1 contained only high-risk patients: group B and a "virtual" group A with similar characteristics. Model 2 included only low-risk patients: group A and "virtual" group B with identical attributes. The efficacy of entropy balancing was evaluated with the d value. The overall survival was compared and reported with Hazard Ratio (HR) within a confidence interval of 95% (95 CI).ResultsThe groups A and B were imbalanced for tumor size (d = 0.392), T (d = 1.128), N (d = 1.340), M (d = 1.456), mean number of positive lymph nodes (d = 0.907), and LNR (d = 0.889). Before the balancing, the risk of death was higher in group B than in A (4.3; 2.5 to 7.4). After reweighting, all large differences were eliminated (d < 0.200). In high-risk patients, the risk of death was higher in patients who underwent surgery alone than those who received perioperative chemotherapy (HR 0.5; 0.2 to 1.3) without statistical significance (p = 0.187). In low-risk patients, the risk of death was similar (HR 1.1; 0.3 to 3.3).ConclusionPerioperative chemotherapy could provide some marginal advantages to high-risk patients

    Specific Involvement of Pilus Type 2a in Biofilm Formation in Group B Streptococcus

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    Streptococcus agalactiae is the primary colonizer of the anogenital mucosa of up to 30% of healthy women and can infect newborns during delivery and cause severe sepsis and meningitis. Persistent colonization usually involves the formation of biofilm and increasing evidences indicate that in pathogenic streptococci biofilm formation is mediated by pili. Recently, we have characterized pili distribution and conservation in 289 GBS clinical isolates and we have shown that GBS has three pilus types, 1, 2a and 2b encoded by three corresponding pilus islands, and that each strain carries one or two islands. Here we have investigated the capacity of these strains to form biofilms. We have found that most of the biofilm-formers carry pilus 2a, and using insertion and deletion mutants we have confirmed that pilus type 2a, but not pilus types 1 and 2b, confers biofilm-forming phenotype. We also show that deletion of the major ancillary protein of type 2a did not impair biofilm formation while the inactivation of the other ancillary protein and of the backbone protein completely abolished this phenotype. Furthermore, antibodies raised against pilus components inhibited bacterial adherence to solid surfaces, offering new strategies to prevent GBS infection by targeting bacteria during their initial attachment to host epithelial cells

    Virtual Reality Combined With Psychoeducation to Improve Emotional Well‐Being in Informal Caregivers of Alzheimer's Disease Patients: Rationale and Study Design of a Randomized Controlled Trial

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    Objectives: Care for community-dwelling people with dementia is frequently delegated to relatives, who find themselves in the role of informal caregivers with no practical management knowledge. This situation exposes caregivers to increased risk for emotional wellbeing. The current study aims to test whether the integration of the efficacy of an immersive virtual reality (VR) experience into an online psychoeducational program impacts caregiver empathy and therefore emotional wellbeing. Methods: One-hundred informal caregivers of mild-to-moderate Alzheimer's disease (AD) patients will be enrolled and randomly assigned to (i) an online psychoeducational program (control arm); or (ii) an online psychoeducational program integrated with VR (experimental arm). VR will consist of 360-degree videos involving the caregivers to an immersive experience of dementia symptoms from the patient's perspective. Before, after the intervention and after 2 months, all participants will complete validated clinical scales for caregiver burden and anxiety (primary outcomes) and sense of competence and dispositional empathy (secondary outcomes). A subsample of 50 participants will also undergo MRI exam, including structural and functional (resting-state and task-functional MRI [fMRI]) sequences. The fMRI task paradigm will use emotional stimuli to evaluate the neural correlate of empathy, by stressing its cognitive and affective components. The main outcome will be the change in the clinical assessment; the secondary outcome will be the change in brain connectivity of networks subserving the empathic and emotional functioning. Results: We expect that the psychoeducational program will decrease anxiety and stress, enabling caregivers to perceive themselves capable of managing AD patients at home, educating them on symptom handling and boosting their cognitive empathy. In the experimental intervention, the VR-based experience will act as an add-on to psychoeducation, leading to greater improvement in the assessed clinical dimensions. VR should, in fact, enable a deeper understanding of disease symptoms and improve caregivers' cognitive empathy. We expect that the experimental intervention will result in deeper comprehension of disease symptoms and further strengthen caregivers' cognitive empathy. At the neural level, we expect to observe increased activation in circuits subserving cognitive empathy and decreased activation in circuits underlying affective empathy. Conclusions: To the best of our knowledge, this will be the first randomized controlled trial assessing the effect of combining psychoeducational interventions with VR-based experience in caregivers, and assessing both clinical and imaging outcomes. Trial Registration: Registered in ClinicalTrials.gov (NCT05780476)
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