Selective augmentation of striatal functional connectivity following NMDA receptor antagonism: implications for psychosis

The psychotomimetic effect of the N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine is thought to arise from a functional modulation of the brain's fronto-striato-thalamic (FST) circuits. Animal models suggest a pronounced effect on ventral ‘limbic' FST systems, although recent work in patients with psychosis and high-risk individuals suggests specific alterations of dorsal ‘associative' FST circuits. Here, we used functional magnetic resonance imaging to investigate the effects of a subanesthetic dose of ketamine on measures of functional connectivity as indexed by the temporal coherence of spontaneous neural activity in both dorsal and ventral FST circuits, as well as their symptom correlates. We adopted a placebo-controlled, double-blind, randomized, repeated-measures design in which 19 healthy participants received either an intravenous saline infusion or a racemic mixture of ketamine (100 ng/ml) separated by at least 1 week. Compared with placebo, ketamine increased functional connectivity between the dorsal caudate and both the thalamus and midbrain bilaterally. Ketamine additionally increased functional connectivity of the ventral striatum/nucleus accumbens and ventromedial prefrontal cortex. Both connectivity increases significantly correlated with the psychosis-like and dissociative symptoms under ketamine. Importantly, dorsal caudate connectivity with the ventrolateral thalamus and subthalamic nucleus showed inverse correlation with ketamine-induced symptomatology, pointing to a possible resilience role to disturbances in FST circuits. Although consistent with the role of FST in mediating psychosis, these findings contrast with previous research in clinical samples by suggesting that acute NMDAR antagonism may lead to psychosis-like experiences via a mechanism that is distinct from that implicated in frank psychotic illness

Exploring the common blockchain adoption enablers: the case of three Italian wineries

Purpose: This study aims to explore and describe the main enabling factors affecting the implementation of blockchain technology (BCT) in a strategic sector such as the wine industry, as well as the motivation behind this choice. Design/methodology/approach: In light of the novelty of the phenomenon studied, a case study approach was adopted analyzing three Italian wineries. A conceptual framework, based on the dynamic capabilities, absorptive capacity and dominant logic theories, was developed. Primary and secondary data were collected. Findings: Results show that wineries working in a highly dynamic and competitive market invest more in knowledge acquisition and internal assimilation and less in transformation and exploitation of acquired knowledge, in particular preferring to outsource the application phase of BCT. The particularity of the wine industry, indeed, demonstrates the existence of hybrid alternatives in which exploration and exploitation processes can be balanced. These findings confirm the value of the conceptual framework developed to explain how wineries implement BCT in their business. Research limitations/implications: The present work must be considered in light of the research scope and its qualitative nature. Practical implications: Findings suggest that the adoption of BCT depends on the wineries’ ability to invest more in effective knowledge management systems to acquire and assimilate knowledge internally and in managerial skills and dominant logic that become strategic resources that can improve their innovation performance. Originality/value: Compared to previous studies on BCT adoption in the wine industry, this work helps us to better understand how wineries implement BCT as it focuses on their ability to acquire, manage and capitalize on the flow of knowledge, as a strategic resource, which forms the basis for creating dynamic capabilities and value. Findings are of interest to develop strategies aimed to ensure the effectiveness of this innovation in a strategic sector

Upper Urinary Tract Transitional Cell Tumors Diagnosis: Role of CT - Urography

Abstract Objective: The purpose of this study was to point out CT Urography (CTU) potentials and limitations for the diagnosis of Upper Urinary Tract Transitional Cell Carcinoma (UUT-TCC) and to suggest how and when to use invasive second-line investigations. Materials and Methods: 66 patients with a suspected UUT-TCC were examined with CTU; 52/66 patients underwent also Retrograde Pielography (RP). Reference standards were histopathology and the 24-month clinical and imaging follow-up. Moreover the T stage of 15 tumors, treated by surgery, was assessed. Results: 21/66 patients had a final diagnosis of UUT-TCC; CTU showed a sensitivity of 90.5%, a specificity of 84.4%, a Positive Predictive Value (PPV) of 73.1% and a Negative Predictive Value (NPV) of 95%. The overall accuracy of CTU in evaluation of T parameter was 80%. In the subgroup of 52 patients, CTU and RP showed both a sensitivity of 85.7%, a specificity respectively of 84.4% and 82.2%, a PPV of 46.2% and 42.8%, a NPV of 97.4% and 97.3%. In 7 cases, false positive both at CTU and RP, biopsy allowed a definitive diagnosis of tumor absence. Moreover in 1 case, false negative both at CTU and RP with positive urinary cytology, endoscopy and biopsy showed a small superficial tumor. Conclusion: CTU, complemented by urinary cytology and cystoscopy, is the technique of choice for UUT-TCC diagnosis and staging. In cases of positive CT findings, RP-guided biopsy is advisable to complete the diagnostic work-up; nevertheless, if CTU is negative and cytology is positive, endoscopy is indicated

Factors predicting outcomes of microwave ablation of small hepatocellular carcinoma

Purpose: The aim of our study was to evaluate factors influencing effectiveness of percutaneous microwave ablation (MWA) in patients with small hepatocellular carcinoma (HCC) (3 cm from the capsule) (n = 22) and peripheral (<3 cm from the capsule) (n = 43). Imaging follow-up was performed at 1, 3, 6, and 12 months after treatment, then annually. Mean follow-up period was 18 months (range 1\u201355). Location of the lesion, age, sex, and underlying disease of the patients was analyzed and related with efficacy. Results: Technical success was obtained in all cases. Residual disease was registered in 21 lesions (32.3 %): 13 were peripheral and 8 were central. Twelve of them were retreated with percutaneous MWA. Local recurrence was recorded in 8 lesions (12.3 %): 5 were retreated with MWA. No significant difference in terms of effectiveness was observed in lesions located in a central position and those situated in the peripheral position. Age, sex, and underlying disease not influenced results. Only one major complication was observed. The rate of minor complications was 24.5 %. Mortality at 30 days was 0 %. Conclusions: Our results encourage the role of MWA in the treatment of small HCC. More numerous series and randomized studies are necessary to state the role of MWA and to select cases in which MWA may be more effective and safer than RFA

Evaluation of tablet ultrasound for routine abdominal interventional procedures

Aim: The aim of the study was to establish if a novel tablet ultrasound (US) may replace a high-end US machine during routine interventional radiology activities. Materials and methods: Thirty consecutive patients were evaluated by two operators comparing the performance of the new US tablet system (VISIQ, Philips Healthcare) against a high-end US system (iU22, Philips Healthcare) using a curved probe (C5-2). A structured questionnaire was used to rank on a 4-point scale the ability of each system to locate a target as detected by previous examinations and visualize needles and path during an interventional procedure. Necessity for conversion from the tablet US to the high-end US system was registered; body mass index (BMI) was annotated for each patient. Results: Agreement between the operators was found for every patient. Mean patient BMI was 25 (range 17\u201334). Image quality of the tablet US was considered insufficient in 1 case to visualize the target and in another case to visualize the needle. Mean target image quality was superior with the high-end US system, while needle visibility scored higher with the tablet US. Conversion to the high-end system was registered in 40 % of cases: in most cases (66.6 %) the decision was due to the absence of a dedicated needle guide for the tablet US. Conclusions: The novel tablet US was found to provide sufficient image quality for the majority of routine interventional procedures. Dedicated accessories and additional experience with this new generation US device may be needed to replace bulky high-end US systems