High frame-rate contrast enhanced ultrasound (HIFR-CEUS) in the characterization of small hepatic lesions in cirrhotic patients.

BACKGROUND: To show the effectiveness of plane wave HighFrame-Rate CEUS (HiFR-CEUS) compared with "conventional" (plane wave) CEUS (C-CEUS) in the characterization of small (< 2 cm) focal liver lesions (FLLs) not easily detected by CT in cirrhotic patients. HiFR-CEUS exploit an ultra-wideband nonlinear process to combine fundamental, second and higher-order harmonic signals generated by ultrasound contrast agents to increase the frame rate. C-CEUS is limited by the transmission principle, and its frame-rate is around 10 FPS. With HiFR-CEUS (Shenzhen Mindray Bio-Medical Electronics Co., China), the frame-rate reached 60 FPS. MATERIAL AND METHODS: Ultrasound detected small FLLs (< 2 cm) in 63 cirrhotic patients during follow-up (June 2019-February 2020); (7 nodules < 1 cm and were not evaluable by spiral CT). Final diagnosis was obtained with MRI (47) or fine needle aspiration (16 cases) C-CEUS was performed and HiFR-CEUS was repeated after 5 min; 0.8-1.2 ml of contrast media (SonoVue, Bracco, Italy) was used. 57 nodules were better evaluable with HiFR-CEUS; 6 nodules were equally evaluable by both techniques; final diagnosis was: 44 benign lesions (29 hemangiomas, 1 amartoma, 2 hepatic cysts; 2 focal nodular hyperplasias, 3 regenerative macronodules, 3 AV-shunts, 3 hepatic sparing areas and 1 focal steatosis) and 19 malignant one (17 HCCs, 1 cholangioca, 1 metastasis); statistical evaluation for better diagnosis with X2 test (SPSS vers. 26); we used LI-RADS classification for evaluating sensitivity, specificity PPV, NPV and diagnostic accuracy of C- and HFR-CEUS. Corrispective AU-ROC were calculated. RESULTS: C-CEUS and HiFR-CEUS reached the same diagnosis in 29 nodules (13 nodules > 1 < 1.5 cm; 16 nodules > 1.5 < 2 cm); HiFR-CEUS reached a correct diagnosis in 32 nodules where C-CEUS was not diagnostic (6 nodules < 1 cm; 17 nodules > 1 < 1.5 cm; 9 nodules > 1.5 < 2 cm); C-CEUS was better in 2 nodules (1 < 1 cm and 1 > 1 < 1.5 cm). Some patient's (sex, BMI, age) and nodule's characteristics (liver segment, type of diagnosis, nodule's dimensions (p = 0.65)) were not correlated with better diagnosis (p ns); only better visualization (p 0.004) was correlated; C-CEUS obtained the following LI-RADS: type-1: 18 Nodules, type-2: 21; type-3: 7, type-4: 7; type-5: 8; type-M: 2; HiFR-CEUS: type-1: 38 Nodules, type-2: 2; type-3:4, type-4: 2; type-5: 15; type-M: 2; In comparison with final diagnosis: C-CEUS: TP: 17; TN: 39; FP: 5; FN:2; HIFR-CEUS: TP: 18; TN: 41; FP: 3; FN:1; C-CEUS: sens: 89.5%; Spec: 88.6%, PPV: 77.3%; NPV: 95.1%; Diagn Acc: 88.6% (AU-ROC: 0.994 ± SEAUC: 0.127; CI: 0.969-1.019); HiHFR CEUS: sens: 94.7%; Spec: 93.2%, PPV: 85.7%; NPV: 97.6%; Diagn Acc: 93.2% (AU-ROC: 0.9958 ± SEAUC: 0.106; CI: 0.975-1.017) FLL vascularization in the arterial phase was more visible with HiFR-CEUS than with C-CEUS, capturing the perfusion details in the arterial phase due to a better temporal resolution. With a better temporal resolution, the late phase could be evaluated longer with HiFR-CEUS (4 min C-CEUS vs. 5 min HiFR-CEUS). CONCLUSION: Both C-CEUS and HIFR-CEUS are good non invasive imaging system for the characterization of small lesions detected during follow up of cirrhotic patients. HiFR-CEUS allowed better FLL characterization in cirrhotic patients with better temporal and spatial resolution capturing the perfusion details that cannot be easily observed with C-CEUS.

One-Year stable perovskite solar cells by 2D/3D interface engineering.

Despite the impressive photovoltaic performances with power conversion efficiency beyond 22%, perovskite solar cells are poorly stable under operation, failing by far the market requirements. Various technological approaches have been proposed to overcome the instability problem, which, while delivering appreciable incremental improvements, are still far from a market-proof solution. Here we show one-year stable perovskite devices by engineering an ultra-stable 2D/3D (HOOC(CH2)4NH3)2PbI4/CH3NH3PbI3 perovskite junction. The 2D/3D forms an exceptional gradually-organized multi-dimensional interface that yields up to 12.9% efficiency in a carbon-based architecture, and 14.6% in standard mesoporous solar cells. To demonstrate the up-scale potential of our technology, we fabricate 10 × 10 cm2 solar modules by a fully printable industrial-scale process, delivering 11.2% efficiency stable for >10,000 h with zero loss in performances measured under controlled standard conditions. This innovative stable and low-cost architecture will enable the timely commercialization of perovskite solar cells.

CH3NH3PbI3 perovskite single crystals: surface photophysics and their interaction with the environment.

Here we identify structural inhomogeneity on a micrometer scale across the surface of a CH3NH3PbI3 perovskite single crystal. At the crystal edge a local distortion of the crystal lattice is responsible for a widening of the optical bandgap and faster photo-carrier recombination. These effects are inherently present at the edge of the crystal, and further enhanced upon water intercalation, as a preliminary step in the hydration of the perovskite material.

Different quantification algorithms may lead to different results: a comparison using proton MRS lipid signals.

Proton magnetic resonance spectroscopy (MRS) is a sensitive method for investigating the biochemical compounds in a tissue. The interpretation of the data relies on the quantification algorithms applied to MR spectra. Each of these algorithms has certain underlying assumptions and may allow one to incorporate prior knowledge, which could influence the quality of the fit. The most commonly considered types of prior knowledge include the line-shape model (Lorentzian, Gaussian, Voigt), knowledge of the resonating frequencies, modeling of the baseline, constraints on the damping factors and phase, etc. In this article, we study whether the statistical outcome of a biological investigation can be influenced by the quantification method used. We chose to study lipid signals because of their emerging role in the investigation of metabolic disorders. Lipid spectra, in particular, are characterized by peaks that are in most cases not Lorentzian, because measurements are often performed in difficult body locations, e.g. in visceral fats close to peristaltic movements in humans or very small areas close to different tissues in animals. This leads to spectra with several peak distortions. Linear combination of Model spectra (LCModel), Advanced Method for Accurate Robust and Efficient Spectral fitting (AMARES), quantitation based on QUantum ESTimation (QUEST), Automated Quantification of Short Echo-time MRS (AQSES)-Lineshape and Integration were applied to simulated spectra, and area under the curve (AUC) values, which are proportional to the quantity of the resonating molecules in the tissue, were compared with true values. A comparison between techniques was also carried out on lipid signals from obese and lean Zucker rats, for which the polyunsaturation value expressed in white adipose tissue should be statistically different, as confirmed by high-resolution NMR measurements (considered the gold standard) on the same animals. LCModel, AQSES-Lineshape, QUEST and Integration gave the best results in at least one of the considered groups of simulated or in vivo lipid signals. These outcomes highlight the fact that quantification methods can influence the final result and its statistical significance.

Fast and minimally invasive determination of the unsaturation index of white fat depots by micro-Raman spectroscopy.

In the last 20 years increasing interest has been devoted to the investigation of white adipose tissue (WAT) because hypo- or hyperfunction of WAT is involved in the pathogenesis of obesity and other pathologies. The investigation and discrimination of different characteristics in adipose tissues by means of spectroscopic techniques appears as a topic of current interest, also in view of possible medical-technological applications. The aim of this work was to establish micro-Raman spectroscopy as a tool for the characterization of mammals fat tissue. After preliminary tests aimed at defining a suitable sample preparation protocol, Raman spectra of WAT specimens excised from mice of different ages were recorded in the energy range 750-3,350 cm⁻¹. Quantitative values of the unsaturation index were obtained through the calibration with HR-NMR spectra of lipid extracts. Raman spectroscopy detected a sharp increase in the unsaturation index between 22 and 30 days of age in close correspondence with the weaning of mice (21 days). The present results show that Raman spectroscopy is an inexpensive, fast and robust technique to analyze the unsaturation index of mammals fat tissues that could be routinely used in bioptic samples.

Breast milk immune complexes are potent inducers of oral tolerance in neonates and prevent asthma development.

Allergic asthma is a chronic lung disease resulting from an inappropriate T helper (Th)-2 response to environmental antigens. Early tolerance induction is an attractive approach for primary prevention of asthma. Here, we found that breastfeeding by antigen-sensitized mothers exposed to antigen aerosols during lactation induced a robust and long-lasting antigen-specific protection from asthma. Protection was more profound and persistent than the one induced by antigen-exposed non-sensitized mothers. Milk from antigen-exposed sensitized mothers contained antigen-immunoglobulin (Ig) G immune complexes that were transferred to the newborn through the neonatal Fc receptor resulting in the induction of antigen-specific FoxP3(+) CD25(+) regulatory T cells. The induction of oral tolerance by milk immune complexes did not require the presence of transforming growth factor-beta in milk in contrast to tolerance induced by milk-borne free antigen. Furthermore, neither the presence of IgA in milk nor the expression of the inhibitory FcgammaRIIb in the newborn was required for tolerance induction. This study provides new insights on the mechanisms of tolerance induction in neonates and highlights that IgG immune complexes found in breast milk are potent inducers of oral tolerance. These observations may pave the way for the identification of key factors for primary prevention of immune-mediated diseases such as asthma.

Value of magnetic resonance imaging in the evaluation of sex-reassignment surgery in male-to-female transsexuals.

BACKGROUND: We investigated the value of magnetic resonance imaging (MRI) in the evaluation of sex-reassignment surgery in male-to-female transsexual patients. METHODS: Ten male-to-female transsexual patients who underwent sex-reassignment surgery with inversion of combined penile and scrotal skin flaps for vaginoplasty were examined after surgery with MRI. Turbo spin-echo T2-weighted and spin-echo T1-weighted images were obtained in sagittal, coronal, and axial planes with a 1.5-T superconductive magnet. Images were acquired with and without an inflatable silicon vaginal tutor. The following parameters were evaluated: neovaginal depth, neovaginal inclination in the sagittal plane, presence of remnants of the corpus spongiosum and corpora cavernosa, and thickness of the rectovaginal septum. RESULTS: The average neovaginal depth was 7.9 cm (range = 5-10 cm). The neovagina had a correct oblique inclination in the sagittal plane in four patients, no inclination in five, and an incorrect inclination in one. In seven patients, MRI showed remnants of the corpora cavernosa and/or of the corpus spongiosum; in three patients, no remnants were detected. The average thickness of the rectovaginal septum was 4 mm (range = 3-6 mm). CONCLUSION: MRI allows a detailed assessment of the pelvic anatomy after genital reconfiguration and provides information that can help the surgeon to adopt the most correct surgical approach.

[Ultrasonography plus direct radiography of the abdomen in the diagnosis of renal colic: still a valid approach?]. / Ecografia e radiogramma diretto dell'addome nella diagnostica della colica renale: un approccio ancora valido?

PURPOSE: The authors analyze whether the imaging approach consisting of ultrasonography and plain film in patients with renal colic is still of value when urography is replaced by unenhanced helical CT (UHCT) in unsolved cases. MATERIAL AND METHODS: Eight hundred and three consecutive patients were investigated with US following hydration and KUB, 164 of whom (20.4%) subsequently underwent UHCT (42 with the aim of mapping the excretory pathway and 122 (15.2%) because US and KUB were not considered as fully diagnostic). RESULTS: The 42 patients with detectable ureteral stone (plus possible hydronephrosis) on KUB + US and subsequently examined by UHCT to plan interventional treatment all had a positive UHCT examination. In 62 patients the diagnosis following KUB + US was uncertain (possible stone or possible hydronephrosis) and UHCT depicted the stone and/or the hydronephrosis in 34. In 60 patients the combination of KUB + US was negative but colic recurred and UHCT was positive in 17 patients. DISCUSSION: The comparison of the present results with a previous study in which KUB and US were followed by IVU in unsolved cases underscores the value of the first approach with KUB and US. The need for further diagnostic investigations when KUB + US are either not conclusive or negative and colic recurs is also confirmed. On the basis of our present data and in agreement with the literature IVU can be safely replaced by UHCT. CONCLUSIONS: It is authors' opinion that in settings where KUB, US and UHCT are available throughout the 24 hr the approach consisting of KUB plus US and UHCT in unsolved cases can be preferred in view of its on lower cost and above all lower X-ray dose to patients as compared to UHCT as the sole investigation.

Representación del concepto de prevención-salud, integrado al servicio comunitario / Representation of the prevention-health concept, integrated to the community service

Existen causas muy claras por lo que la odontología ha ido redefiniendo sus objetivos en relación a la formación de recursos humanos, los cuales deben ser capaces de desarrollar acciones necesarias para prevenir y promover la salud bucodental. La comunidad tiene necesidades de salud y es función del profesional responder a esas demandas. La construcción de un perfil profesional diferente le ayudará a tomar contacto con la realidad cada vez más cambiante. El objetivo de esta investigación es evaluar el desempeño de los recursos humanos formados en la Facultad de Odontología de la Universidad Nacional de La Plata para acciones comunitarias. Esta investigación consistió en un estudio de tipo descriptivo, el universo a estudiar lo constituyeron los egresados de la Facultad, pertenecientes a los planes 1990 y 1994, la recopilación de documentación se obtuvo mediante una encuesta estructurada y entrevistas presonales. De un total de 941 egresados se obtuvo información de 519 (55,10 por ciento) de los cuales 454 (87,48 por ciento) corresponden al plan 19990 y 65 (12,57 por ciento) al plan 1994. Las encuestas brindaron elementos para determinar conclusiones parciales, siendo las mismas favorables en cuanto a la formación preventiva con respecto a la toma de decisiones en los procesos sociales hacia los egresados formados en la Reforma Curricular de 1994 (AU)

Representación del concepto de prevención-salud, integrado al servicio comunitario / Representation of the prevention-health concept, integrated to the community service

Existen causas muy claras por lo que la odontología ha ido redefiniendo sus objetivos en relación a la formación de recursos humanos, los cuales deben ser capaces de desarrollar acciones necesarias para prevenir y promover la salud bucodental. La comunidad tiene necesidades de salud y es función del profesional responder a esas demandas. La construcción de un perfil profesional diferente le ayudará a tomar contacto con la realidad cada vez más cambiante. El objetivo de esta investigación es evaluar el desempeño de los recursos humanos formados en la Facultad de Odontología de la Universidad Nacional de La Plata para acciones comunitarias. Esta investigación consistió en un estudio de tipo descriptivo, el universo a estudiar lo constituyeron los egresados de la Facultad, pertenecientes a los planes 1990 y 1994, la recopilación de documentación se obtuvo mediante una encuesta estructurada y entrevistas presonales. De un total de 941 egresados se obtuvo información de 519 (55,10 por ciento) de los cuales 454 (87,48 por ciento) corresponden al plan 19990 y 65 (12,57 por ciento) al plan 1994. Las encuestas brindaron elementos para determinar conclusiones parciales, siendo las mismas favorables en cuanto a la formación preventiva con respecto a la toma de decisiones en los procesos sociales hacia los egresados formados en la Reforma Curricular de 1994

Expression of dipeptidylaminopeptidase IV/CD26 in peripheral blood lymphocytes of hemophilic subjects.

CD26 antigen, a 110 kDa membrane glycoprotein with exopeptidase activity (DAP IV), is an activation marker of T lymphocytes preferentially expressed on CD4+ memory cells and involved in T cell proliferation and IL-2 production after antigenic stimulation. We employed cytochemical and immunocytochemical techniques to study DAP IV/CD26 expression in circulating lymphocytes from 40 hemophilic patients, chronically treated with coagulation factors, in order to verify the possible involvement of this molecule in the immunological alterations of hemophilia. In all the hemophiliacs DAP IV activity was significantly lower than in the controls, independently of the quantity of blood transfused and previous exposure to viruses. This reduction may be responsible for the impaired proliferative response of lymphocytes to antigens and mitogens, notoriously observed in hemophilia. Whereas in the group of HIV- patients CD26 expression was similar to that of normal controls, in the 8 HIV+ hemophilic patients both percentages of positive lymphocytes and intensity of staining were significantly lower. In only 4 of the 8 cases was this deficit associated with CD4+ cell depletion. The significant selective loss of CD26 expression observed in HIV+ patients is probably an early event after HIV infection and seems to occur even before CD4 cell depletion. In conclusion, evaluation of DAP IV/CD26 might be a useful option for monitoring the immunological alterations of all hemophilic patients, HIV positive or not, chronically treated with coagulation factors.