121 research outputs found
Image-guided Breast Biopsy of MRI-visible Lesions with a Hand-mounted Motorised Needle Steering Tool
A biopsy is the only diagnostic procedure for accurate histological
confirmation of breast cancer. When sonographic placement is not feasible, a
Magnetic Resonance Imaging(MRI)-guided biopsy is often preferred. The lack of
real-time imaging information and the deformations of the breast make it
challenging to bring the needle precisely towards the tumour detected in
pre-interventional Magnetic Resonance (MR) images. The current manual
MRI-guided biopsy workflow is inaccurate and would benefit from a technique
that allows real-time tracking and localisation of the tumour lesion during
needle insertion. This paper proposes a robotic setup and software architecture
to assist the radiologist in targeting MR-detected suspicious tumours. The
approach benefits from image fusion of preoperative images with intraoperative
optical tracking of markers attached to the patient's skin. A hand-mounted
biopsy device has been constructed with an actuated needle base to drive the
tip toward the desired direction. The steering commands may be provided both by
user input and by computer guidance. The workflow is validated through phantom
experiments. On average, the suspicious breast lesion is targeted with a radius
down to 2.3 mm. The results suggest that robotic systems taking into account
breast deformations have the potentials to tackle this clinical challenge.Comment: Submitted to 2021 International Symposium on Medical Robotics (ISMR
Noncommutative geometry inspired charged black holes
We find a new, non-commutative geometry inspired, solution of the coupled
Einstein-Maxwell field equations describing a variety of charged,
self-gravitating objects, including extremal and non-extremal black holes. The
metric smoothly interpolates between deSitter geometry, at short distance, and
Reissner-Nordstroem geometry far away from the origin. Contrary to the ordinary
Reissner-Nordstroem spacetime there is no curvature singularity in the origin
neither "naked" nor shielded by horizons. We investigate both the Hawking
process and pair creation in this new scenario.Comment: 14 pages, 9 figure, LaTe
Characterization of nitrogen dioxide variability using ground-based and satellite remote sensing and in situ measurements in the Tiber valley (Lazio, Italy)
The spatial-temporal distributions of nitrogen dioxide (NO2) in a rural area of Tiber valley were evaluated over one year (March 2022-February 2023) using remote sensing and in situ measurements. Surface concentration monitoring was conducted using a Pandora-2s spectrometer and a chemiluminescence analyzer operated at the Liberti Observatory (CNR-IIA). In spring, when the growing season and the agricultural activities increase, NO2 peaks were detectable by the Pandora but not by the in situ analyzer. The tropospheric Pandora and TROPOMI VCD products showed similar temporal patterns as those of the analyzer at the Observatory. High TROPOMI VCD levels in spring were detected at the Observatory and at six sites selected as representative of rural, residential, and industrial environments. WRF simulations found that high pollution events, observed by the Pandora and analyzer, occurred in calm wind conditions, favouring the accumulation of NO2 locally emitted. The complementary dataset provided by remote sensing and in situ techniques efficiently captured the spatial-temporal NO2 variability in a rural site exposed to low emission sources, thus supporting future decisional policies and actions
Frataxin mRNA isoforms in FRDA patients and normal subjects: effect of tocotrienol supplementation.
Friedreich's ataxia (FRDA) is caused by deficient expression of the mitochondrial protein frataxin involved in the formation of iron-sulphur complexes, and by consequent oxidative stress. We analysed low-dose tocotrienol supplementation effects on the expression of the three splice variant isoforms (FXN-1, FXN-2 and FXN-3) in mononuclear blood cells of FRDA patients and healthy subjects. In FRDA patients, tocotrienol leads to a specific and significant increase of FXN-3 expression, while not affecting FXN-1 and FXN-2 expression. Since no structural and functional details were available for FNX-2 and FXN-3, 3D-models were built. FXN-1, the canonical isoform, was then docked on the human iron-sulphur complex and functional interactions were computed; when FXN-1 was replaced by FXN-2 or FNX-3, we found that the interactions were maintained, thus suggesting a possible biological role for both isoforms in human cells. Finally, in order to evaluate whether tocotrienol enhancement of FXN-3 was mediated by an increase in peroxisome proliferator-activated receptor-\uf067 (PPARG), PPARG expression was evaluated. At low dose of tocotrienol, the increase of FXN-3 expression appeared to be independent of PPARG expression. Our data show that it is possible to modulate the mRNA expression of the minor frataxin isoforms, and that they may have a functional role
The QCD Membrane
In this paper we study spatially quenched, SU(N) Yang-Mills theory in the
large-N limit. The resulting reduced action shows the same formal look as the
Banks-Fischler-Shenker-Susskind M-theory action. The Weyl-Wigner-Moyal symbol
of this matrix model is the Moyal deformation of a p(=2)-brane action. Thus,
the large-N limit of the spatially quenched SU(N) Yang-Mills is seen to
describe a dynamical membrane. By assuming spherical symmetry we compute the
mass spectrum of this object in the WKB approximation.Comment: 14 pages, LaTeX, non figures; accepted for publication in
Class.Quant. Gra
Ovarian tissue cryopreservation and transplantation: 20 years experience in Bologna University
Objective: To report the 20-year experience in ovarian tissue cryopreservation
(OTC) and ovarian tissue transplantation (OTT) of the Bologna clinical center
(Bologna, Italy).
Design: Retrospective cohort study.
Patients: 1026 pediatrics and women aged between 2 and 38 years who
underwent OTC and OTT between January 2002 to January 2022.
Results: Of the 1026 patients, 238 (22.8%) were pediatrics (≤ 17 years, Group 1)
and 788 (77.2%) were adult women (range 18-38 years, Group 2). In Group 1,
184 (77.3%) patients had malignant diseases and 54 (22.7%) had non-malignant
diseases. In Group 2, 746 (94.7%) patients had malignant diseases and 42 (5.3%)
had non-malignant diseases. No real complications were observed during
surgery. In all the samples analyzed most of the follicles were in the resting
stage, while only a few follicles were growing. In both fresh and thawed
samples, follicular density was higher in Group 1 than in Group 2 (p < 0.01).
Regardless of age, good preservation of follicles and stroma was observed in
fresh and thawed ovarian tissue by histological and immunohistochemical
analyses (estrogen and progesterone receptors; Ki67 and Bcl2 markers;
TUNEL). To date, out of 1026 total women, 812 (79.1%) had their tissue
stored. Sixty-eight (6.6%) patients died from their primary disease. Twentyfour
(2.3%) women performed 33 OTTs between December 2011 and January
2022. Restoration of menstruation was observed in 15 out of 17 menopausal
women. Six pregnancies were achieved, two hesitated in abortion and four in
the birth of healthy babies.
Conclusion: OTC is the only fertility preservation technique applicable in prepubertal/
pediatrics and in adult patients when stimulation for oocytes/embryos
cryopreservation is not possible. The reported data can help future patients and
physicians in their discussions and decisions about the need and possibilities of
preserving ovarian function
Resources and tools for rare disease variant interpretation
: Collectively, rare genetic disorders affect a substantial portion of the world's population. In most cases, those affected face difficulties in receiving a clinical diagnosis and genetic characterization. The understanding of the molecular mechanisms of these diseases and the development of therapeutic treatments for patients are also challenging. However, the application of recent advancements in genome sequencing/analysis technologies and computer-aided tools for predicting phenotype-genotype associations can bring significant benefits to this field. In this review, we highlight the most relevant online resources and computational tools for genome interpretation that can enhance the diagnosis, clinical management, and development of treatments for rare disorders. Our focus is on resources for interpreting single nucleotide variants. Additionally, we present use cases for interpreting genetic variants in clinical settings and review the limitations of these results and prediction tools. Finally, we have compiled a curated set of core resources and tools for analyzing rare disease genomes. Such resources and tools can be utilized to develop standardized protocols that will enhance the accuracy and effectiveness of rare disease diagnosis
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