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Proton resonance frequency shift (PRFS) is currently the gold standard method for magnetic resonance thermometry. However, the linearity between the temperature-dependent phase accumulation and the static magnetic field B 0 confines its use to rather high-field scanners. Applications such as thermal therapies could naturally benefit from lower field MRI settings through leveraging increased accessibility, a lower physical and economical footprint, and further consideration of the technical challenges associated with the integration of heating systems into conventional clinical scanners. T 1 -based thermometry has been proposed as an alternative to the gold standard; however, because of longer acquisition times, it has found clinical use solely with adipose tissue where PRFS fails. At low field, the enhanced T 1 dispersion, combined with reduced relaxation times, make T 1 mapping an appealing candidate. Here, an interleaved Look-Locker-based T 1 mapping sequence was proposed for temperature quantification at 0.1 T. A variable averaging scheme was introduced, to maximize the signal-to-noise ratio throughout T 1 recovery. In calibrated samples, an average T 1 accuracy of 85% ± 4% was achieved in 10 min, compared with the 77% ± 7% obtained using a standard averaging scheme. Temperature maps between 29.0 and 41.7°C were eventually reconstructed, with a precision of 3.0 ± 1.1°C and an accuracy of 1.5 ± 1.0°C. Accounting for longer thermal treatments and less strict temperature constraints, applications such as MR-guided mild hyperthermia treatments at low field could be envisioned., (© 2022 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.)

Background: Variable pressure support ventilation (vPSV) is an assisted ventilation mode that varies the level of pressure support on a breath-by-breath basis to restore the physiological variability of breathing activity. We aimed to compare the effects of vPSV at different levels of variability and pressure support (Δ P S ) in patients with acute respiratory distress syndrome (ARDS). Methods: This study was a crossover randomized clinical trial. We included patients with mild to moderate ARDS already ventilated in conventional pressure support ventilation (PSV). The study consisted of two blocks of interventions, and variability during vPSV was set as the coefficient of variation of the Δ P S level. In the first block, the effects of three levels of variability were tested at constant Δ P S : 0% (PSV 0% , conventional PSV), 15% (vPSV 15% ), and 30% (vPSV 30% ). In the second block, two levels of variability (0% and variability set to achieve ±5 cmH 2 O variability) were tested at two ΔP S levels (baseline Δ P S and Δ P S reduced by 5 cmH 2 O from baseline). The following four ventilation strategies were tested in the second block: PSV with baseline Δ P S and 0% variability (PSV BL ) or ±5 cmH 2 O variability (vPSV BL ), PSV with ΔP S reduced by 5 cmH 2 O and 0% variability (PSV -5 ) or ±5 cmH 2 O variability (vPSV -5 ). Outcomes included gas exchange, respiratory mechanics, and patient-ventilator asynchronies. Results: The study enrolled 20 patients. In the first block of interventions, oxygenation and respiratory mechanics parameters did not differ between vPSV 15% and vPSV 30% compared with PSV 0% . The variability of tidal volume ( V T ) was higher with vPSV 15% and vPSV 30% compared with PSV 0% . The incidence of asynchronies and the variability of transpulmonary pressure ( P L ) were higher with vPSV 30% compared with PSV 0% . In the second block of interventions, different levels of pressure support with and without variability did not change oxygenation. The variability of V T and P L was higher with vPSV -5 compared with PSV -5 , but not with vPSV BL compared with PSV BL . Conclusion: In patients with mild-moderate ARDS, the addition of variability did not improve oxygenation at different pressure support levels. Moreover, high variability levels were associated with worse patient-ventilator synchrony. Clinical Trial Registration: www.clinicaltrials.gov, identifier: NCT01683669., Competing Interests: MG was granted a patent on the variable pressure support ventilation mode of assisted ventilation (noisy PSV), which has been licensed to Dräger Medical AG (Lübeck, Germany). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ball, Sutherasan, Fiorito, Dall'Orto, Maiello, Vargas, Robba, Brunetti, D'Antini, Raimondo, Huhle, Schultz, Rocco, Gama de Abreu and Pelosi.)

Solid tumour growth is often associated with the accumulation of mechanical stresses acting on the surrounding host tissue. Due to tissue nonlinearity, the shear modulus of the peri-tumoural region inherits a signature from the tumour expansion which depends on multiple factors, including the soft tissue constitutive behaviour and its stress/strain state. Shear waves used in MR-elastography (MRE) sense the apparent change in shear modulus along their propagation direction, thereby probing the anisotropic stiffness field around the tumour. We developed an analytical framework for a heterogeneous shear modulus distribution using a thick-shelled sphere approximation of the tumour and soft tissue ensemble. A hyperelastic material (plastisol) was identified to validate the proposed theory in a phantom setting. A balloon-catheter connected to a pressure sensor was used to replicate the stress generated from tumour pressure and growth while MRE data were acquired. The shear modulus anisotropy retrieved from the reconstructed elastography data confirmed the analytically predicted patterns at various levels of inflation. An alternative measure, combining the generated deformation and the local wave direction and independent of the reconstruction strategy, was also proposed to correlate the analytical findings with the stretch probed by the waves. Overall, this work demonstrates that MRE in combination with non-linear mechanics, is able to identify the apparent shear modulus variation arising from the strain generated by a growth within tissue, such as an idealised model of tumour. Investigation in real tissue represents the next step to further investigate the implications of endogenous forces in tissue characterisation through MRE., Competing Interests: The authors have declared that no competing interests exist.

The solid and fluid pressures of tumours are often elevated relative to surrounding tissue. This increased pressure is known to correlate with decreased treatment efficacy and potentially with tumour aggressiveness and therefore, accurate noninvasive estimates of tumour pressure would be of great value. We present a proof-of-concept method to infer the total tumour pressure, that is the sum of the fluid and solid parts, by examining stiffness in the peritumoural tissue with MR elastography and utilising nonlinear biomechanical models. The pressure from the tumour deforms the surrounding tissue leading to changes in stiffness. Understanding and accounting for these biases in stiffness has the potential to enable estimation of total tumour pressure. Simulations are used to validate the method with varying pressure levels, tumour shape, tumour size, and noise levels. Results show excellent matching in low noise cases and still correlate well with higher noise. Percent error remains near or below 10% for higher pressures in all noise level cases. Reconstructed pressures were also calculated from experiments with a catheter balloon embedded in a plastisol phantom at multiple inflation levels. Here the reconstructed pressures generally match the increases in pressure measured during the experiments. Percent errors between average reconstructed and measured pressures at four inflation states are 17.9%, 52%, 23.2%, and 0.9%. Future work will apply this method to in vivo data, potentially providing an important biomarker for cancer diagnosis and treatment.

Paget's disease can arise in the breast (mammary Paget disease) or in other locations (extramammary Paget disease) such as anogenital skin in both males and females (Paget disease of the vulva [PDV]). Underlying adenocarcinoma can be found in some cases. This study aims to report clinical aspects, surgical procedures, outcomes, and recurrences of patients with PDV.A retrospective chart review was conducted on patients with pathologically confirmed diagnosis of PDV managed at the Department of Obstetrics and Gynecology, University of Bari, and the "Giovanni Paolo II" National Cancer Institute in Bari, between 1998 and 2018.Records of 24 cases of PDV were examined. Median age of the patients at diagnosis was 69.3 (range 38-84), diagnosis of synchronous cancer was made in 2 cases and in 2 other cases of metachronous disease. Three patients had previously been diagnosed with other oncological diseases. All patients underwent surgery including wide local excision (6), simple vulvectomy (8), and extended vulvectomy (10). Lymphadenectomy was performed in 2 cases and reconstructions with advancement flaps in 7 cases. Four patients were found to have invasive disease and 1 had inguinal node involvement. Positive margins were found in 11 patients. Wound dehiscence and urethral stenosis were found in 4 and 1 case each. Eight recurrences (33.33%) were observed, regardless of positive surgical margins.PDV has a low rate of malignancy but a high rate of recurrence. It should be diagnosed early to avoid repeated surgery and to reduce symptoms and morbidity.

Intraoperative mechanical ventilation is mandatory during many surgical procedures. Knowledge in this field has been widely derived from the experience in the treatment of patients with acute respiratory distress syndrome in the intensive care unit. However, also in surgical patients without lung injury, mechanical ventilation settings affect the clinical outcome, and in particular the occurrence of postoperative pulmonary complications (PPCs). A deep understanding of respiratory physiology is mandatory for the clinician, in order to tailor ventilation settings based on the specific characteristics of each patient. In this paper we will discuss the basis of lung physiology applied to the mechanical ventilation in the operating room. The role of compliance, tidal volume, positive end-expiratory pressure (PEEP), plateau pressure, driving pressure, stress index, mechanical power and other ventilator-derived parameters will be discussed. The above-mentioned physiological parameters are easy to measure and can guide the clinician to assess and titrate mechanical ventilation parameters, but the clinical impact of guiding mechanical ventilation based on these parameters has yet to be determined., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Background: Emergency physicians are frequently called on to medically clear patients presenting with a psychiatric complaint. There is limited guidance on how to conduct this clearance., Objective: This study evaluated the usefulness of a screening tool in ruling out serious organic disease in emergency department (ED) patients with psychiatric complaints., Methods: A retrospective chart review was performed on 500 consecutive adult ED patients with primarily psychiatric complaints who were evaluated using the tool, and then subsequently transferred to a psychiatric crisis center. The screening tool consists of a series of historical and physical examination criteria derived from the literature intended to identify patients who have a psychiatric manifestation of an organic disease. The physician filled out the screening form and if the proper conditions were met, the patient was transferred to Psychiatry without further laboratory or imaging studies. We reviewed the charts of both the ED visit and the psychiatric crisis center visit to determine if any of the patients required further medical treatment or a medical admission rather than a psychiatric admission., Results: Five hundred consecutive ED patient charts were reviewed. Fifteen of the corresponding charts from the psychiatric center could not be found. Of the remaining 485 patients, 6 patients were sent back to the ED for further evaluation. After laboratory work and imaging, none of these 6 patients required more than an outpatient prescription., Conclusion: The screening tool proved useful in determining if a psychiatric patient needed further medical evaluation beyond a history and physical examination before transfer for a psychiatric evaluation., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Type 2 iodothyronine deiodinase (DIO2) converts thyroid prohormone tetraiodothyronine into the biologically active triiodothyronine hormone, which increases insulin sensitivity at the skeletal muscle level. The DIO2 T92A polymorphism modulates deiodinase activity and has been inconsistently associated with insulin resistance. Also, the P121A polymorphism of the peroxisome proliferator-activated receptor (PPAR) gamma2 gene, which encodes a transcription factor involved in insulin signaling, has been inconsistently associated with insulin resistance. This study was aimed at evaluating the combined effect of DIO2 T92A and PPARgamma2 P12A polymorphisms on insulin resistance-related features in 590 non-diabetic whites. A significant gene-gene interaction was observed in the modulation of systolic (p = 0.01) and diastolic (p = 0.02) blood pressure and metabolic syndrome (p = 0.02), with carriers of both DIO2 A92 and PPARgamma2 A12 variants showing the worst phenotype. This latter interaction was also shown by multifactor dimensionality reduction analysis (p = 0.0045). A peroxisome proliferator response element in the DIO2 promoter was identified by in silico analysis and confirmed by in vitro gel shift mobility assay, thus providing a biological plausibility for the observed gene-gene interaction. If confirmed in other populations, comprising several thousand individuals, these data may help identify individuals at risk for insulin resistance-related abnormalities.

Hb G-San Josè or beta7(A4)Glu-->Gly has been reported in Southern Italian or Mexican families. We have studied four families from Sicily and Campania, Southern Italy. In six carriers, the hemoglobin variant level ranged from 32 to 38%. In four double heterozygotes for Hb G-San Josè and alpha-thalassemia the variant level showed a strong correlation with the alpha-thalassemia genotype. In fact, the variant level was 15% when interacting with the - (alpha)20.5/alphaalpha, 19.6% with the alphaalpha/alphaPoly Aalpha, and 24.8% with alphaalpha/alpha(-5) ntalpha genotypes. In two double heterozygotes for Hb G-San Josè and beta+ -IVS-I-6 (T-->C) the hemoglobin variant level was 67%. These data show that the reduced synthesis of alpha chains causes drastic reduction of probability to form Hb G-San Josè in favor of the formation of Hb A. Moreover, this reduction, (i) correlates with the type of alpha-thalassemia genotype and with the degree of the alpha chain deficiency, and (ii) is, most probably, more marked than the degree of alpha chain reduction. The minor affinity of the beta chain variant for the alpha chains associated with the reduced synthesis of the alpha chains is probably the principal cause of the variant hemoglobin reduction. Moreover, the rapid removal of the abnormal chains by proteolytic enzymes must have an essential role in order to reduce the chain variant pool. These conclusions are in agreement with the results obtained in reticulocyte and in vitro recombination experiments.