T1 Values Research Articles

Usefulness of synthetic MRI for differentiation of IDH-mutant diffuse gliomas and its comparison with the T2-FLAIR mismatch sign.

The T2-FLAIR mismatch sign is a characteristic imaging biomarker for astrocytoma, isocitrate dehydrogenase (IDH)-mutant. However, investigators have provided varying interpretations of the positivity/negativity of this sign given for individual cases the nature of qualitative visual assessment. Moreover, MR sequence parameters also influence the appearance of the T2-FLAIR mismatch sign. To resolve these issues, we used synthetic MR technique to quantitatively evaluate and differentiate astrocytoma from oligodendroglioma. This study included 20 patients with newly diagnosed non-enhanced IDH-mutant diffuse glioma who underwent preoperative synthetic MRI using the Quantification of Relaxation Times and Proton Density by Multiecho acquisition of a saturation-recovery using Turbo spin-Echo Readout (QRAPMASTER) sequence at our institution. Two independent reviewers evaluated preoperative conventional MR images to determine the presence or absence of the T2-FLAIR mismatch sign. Synthetic MRI was used to measure T1, T2 and proton density (PD) values in the tumor lesion. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance. The pathological diagnoses included astrocytoma, IDH-mutant (n = 12) and oligodendroglioma, IDH-mutant and 1p/19q-codeleted (n = 8). The sensitivity and specificity of T2-FLAIR mismatch sign for astrocytoma were 66.7% and 100% [area under the ROC curve (AUC) = 0.833], respectively. Astrocytoma had significantly higher T1, T2, and PD values than did oligodendroglioma (p < 0.0001, < 0.0001, and 0.0154, respectively). A cutoff lesion T1 value of 1580 ms completely differentiated astrocytoma from oligodendroglioma (AUC = 1.00). Quantitative evaluation of non-enhanced IDH-mutant diffuse glioma using synthetic MRI allowed for better differentiation between astrocytoma and oligodendroglioma than did conventional T2-FLAIR mismatch sign. Measurement of T1 and T2 value by synthetic MRI could improve the differentiation of IDH-mutant diffuse gliomas.

Quantitative Evaluation of Noncontrast Magnetic Resonance Enterography for Active Inflammation in Crohn Disease Using Native T1 and T2 Mapping.

The aim of this study was to investigate the utility of native T1 and T2 mapping in the bowel to evaluate disease activity in Crohn disease (CD) using endoscopy as the reference standard. This was a prospective study. Magnetic resonance imaging was performed by using a 1.5-T Philips scanner. We used a modified look-locker inversion recovery and a multiecho gradient-spin-echo sequences for single breath-hold native T1 and T2 maps, respectively, for the short-axis image of the intestine, and the measurement at the most severe site was compared with partial Simple Endoscopic Score for Crohn's Disease (pSES-CD, assessed by an expert endoscopist). A pSES-CD ≥ 4 indicated active disease. Statistical analyses were performed using the Student t test, Spearman correlation, and receiver operating characteristic curve analysis. A total of 27 patients (mean age ± standard deviation, 37 ± 18 years; 20 men, 7 women) were included in this study. The native T1 value of active disease was significantly higher than that of inactive disease (1170.8 ± 100.5 milliseconds vs 924.5 ± 95.3 milliseconds; P = 0.018), but the T2 value was not significantly different between active and inactive disease (76.1 ± 7.8 milliseconds vs 69.3 ± 10.9 milliseconds; P = 0.424). A good correlation was found between native T1 value and pSES-CD (ρ = 0.71; P < 0.001) but not between T2 value and pSES-CD (ρ = 0.06; P = 0.790). The area under the receiver operating characteristic curve for differentiating the disease activity was 0.96 (95% confidence interval [CI]: 0.90-1.00) for T1 values and 0.68 (95% confidence interval: 0.41-0.96) for T2 values. Native T1 mapping could be potentially used as a noninvasive method to differentiate disease activity in patients with CD and may be superior to T2 mapping for this purpose.

Mineralocorticoid Receptor Antagonism Prevents Aortic Plaque Progression and Reduces Left Ventricular Mass and Fibrosis in Patients With Type 2 Diabetes and Chronic Kidney Disease: The MAGMA Trial.

Persistent mineralocorticoid receptor activation is a pathologic response in type 2 diabetes and chronic kidney disease. Whereas mineralocorticoid receptor antagonists are beneficial in reducing cardiovascular complications, direct mechanistic pathways for these effects in humans are lacking. The MAGMA trial (Mineralocorticoid Receptor Antagonism Clinical Evaluation in Atherosclerosis) was a randomized, double-blind, placebo-controlled trial in patients with high-risk type 2 diabetes with chronic kidney disease (not receiving dialysis) on maximum tolerated renin-angiotensin system blockade. The primary end point was change in thoracic aortic wall volume, expressed as absolute or percent value (ΔTWV or ΔPWV), using 3T magnetic resonance imaging at 12 months. Secondary end points were changes in left ventricle (LV) mass; LV fibrosis, measured as a change in myocardial native T1; and 24-hour ambulatory and central aortic blood pressures. Tertiary end points included plasma proteomic changes in 7596 plasma proteins using an aptamer-based assay. A total of 79 patients were randomized to placebo (n=42) or 25 mg of spironolactone daily (n=37). After a modified intent-to-treat, including available baseline data of study end points, patients who completed the trial protocol were included in the final analyses. At the 12-month follow-up, the average change in PWV was 7.1±10.7% in the placebo group and 0.87±10.0% in the spironolactone group (P=0.028), and ΔTWV was 1.2±1.7 cm3 in the placebo group and 0.037±1.9 cm3 in the spironolactone group (P=0.022). Change in LV mass was 3.1±8.4 g in the placebo group and -5.8±8.4 g in the spironolactone group (P=0.001). Changes in LV T1 values were significantly different between the placebo and spironolactone groups (26.0±41.9 ms in the placebo group versus a decrease of -10.1±36.3 ms in the spironolactone group; P=6.33×10-4). Mediation analysis revealed that the spironolactone effect on thoracic aortic wall volume and myocardial mass remained significant after adjustment for ambulatory and central blood pressures. Proteomic analysis revealed a dominant effect of spironolactone on pathways involving oxidative stress, inflammation, and leukocyte activation. Among patients with diabetes with moderate to severe chronic kidney disease at elevated cardiovascular risk, treatment with spironolactone prevented progression of aortic wall volume and resulted in regression of LV mass and favorable alterations in native T1, suggesting amelioration of left-ventricular fibrosis. URL: https://www.clinicaltrials.gov; Unique identifier: NCT02169089.

Effect of chloroquine pre-treatment on the metoclopramide’s pharmacokinetics after their co-administration

ABSTRACT Background This study evaluated the pharmacokinetic interactions of orally administered chloroquine and metoclopramide. Methods The study employed a randomized and two-phase cross-over design with 4-week washout plan. Twelve healthy male volunteers were shortlisted according to the set criteria and were administered with metoclopramide 10 mg PO and chloroquine (a total of 1500 mg) at different intervals which were (500 mg at 0, 6, and 24 h). The concentration of chloroquine and metoclopramide in the blood samples was estimated using a validated HPLC-UV technique to affirm the maximum concentration (Cmax), time to reach Cmax (Tmax), and area under the curve (AUC). Results Cmax, T1/2, and AUC of metoclopramide were increased up to 20, 10, and 47.8%, respectively, by the concomitantly administering Chloroquine. Chloroquine-treated phase showed increased values of Cmax (ng/ml), AUC (ng.h/ml), and T½ (h), i.e. 41.35 ± 1.61, 504.12 ± 66.25, and 5.72 ± 2.63, as compared to that reference phase i.e. 34.52 ± 4.92, 341.14 ± 112.8, and 5.19 ± 1.14, respectively. Conclusions Chloroquine was found to attenuate CYP2D6 activity in healthy Pakistani male volunteers. Hence, patients that are prescribed with metoclopramide or other CYP2D6-substrate drugs require a dose adjustment when administered with chloroquine.

Evaluation of Oxidative Stress, Thyroid Hormones, Trace Elements and Some Biochemical Markers in Goats Naturally Infected with Theileria ovis.

Theileriosis is a tick-borne disease caused by protozoon species in the Theileria genus of the Theileriidae family. The biochemical changes induced by infection are considered to be an important understanding of the pathophysiology of caprine theileriosis. In this study, it was aimed to determine oxidative stress, thyroid hormones, trace elements, and biochemical parameters in theileriosis infection. A sample of 14 goat was used for this purpose, of which 7 were healthy and 7 were infected with Theileria ovis. Theileria infection was diagnosed from the polymerase chain reaction (PCR). Sera from blood samples was tested for total antioxidant capacity (TAC), total oxidant capacity (TOC), oxidative stress index (OSI), alanine aminotransferase (ALT), aspartate transaminase (AST), gamma glutamyl transferase (GGT), total protein, albumin, triglyceride, cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), urea, blood urea nitrogen (BUN), creatinine, triiodothyronine (T3), thyroxine (T4), copper (Cu), zinc (Zn), cobalt (Co), manganese (Mn), selenium (Se), iron (Fe). TOC, OSI, AST, ALT and GGT values were higher in the patient group than in the healthy group (P < 0.05). On the other hand, there were decreases in TAC, T3, T4, total protein, albumin, creatinine, Cu, Zn, Se, and Co values (P < 0.05). However, there was not found to be a statistical difference between the healthy and patient groups in terms of triglyceride, cholesterol, HDL, LDL, urea, BUN, Mn, and Fe values (P > 0.05). It can be stated that oxidative stress is a complication of caprine theileriosis and it may be accompanied with hypothyroidism and deficits in trace minerals.

Fat-signal suppression in breast diffusion-weighted imaging: the Good, the Bad, and the Ugly.

Fat-signal suppression is essential for breast diffusion magnetic resonance imaging (or diffusion-weighted MRI, DWI) as the very low diffusion coefficient of fat tends to decrease absolute diffusion coefficient (ADC) values. Among several methods, the STIR (short-tau inversion recovery) method is a popular approach, but signal suppression/attenuation is not specific to fat contrary to other methods such as SPAIR (spectral adiabatic (or attenuated) inversion recovery). This article focuses on those two techniques to illustrate the importance of appropriate fat suppression in breast DWI, briefly presenting the pros and cons of both approaches. We show here through simulation and data acquired in a dedicated breast DWI phantom made of vials with water and various concentrations of polyvinylpyrrolidone (PVP) how ADC values obtained with STIR DWI may be biased toward tissue componentswith the longest T1 values: ADC values obtained with STIR fat suppression may be over/underestimated depending on the T1 and ADC profile within tissues. This bias is also illustrated in twoclinical examples. Fat-specific methods should be preferred over STIR for fat-signal suppression in breast DWI, such as SPAIR which also provides a higher sensitivity than STIR for lesion detection. One should remain aware, however, that efficient fat-signal suppression with SPAIR requires good B0 shimming to avoid ADC underestimation from residual fat contamination. The spectral adiabatic (or attenuated) inversion recovery (SPAIR) method should be preferred over short-tau inversion recovery (STIR) for fat suppression in breast DWI. Fat-signal suppression is essential for breast DWI; the SPAIR method is recommended. Short-tau inversion recovery (STIR)is not specific to fat; as a result, SNR is decreased and ADC values may be over- or underestimated. The STIR fat-suppression method must not be used after the injection of gadolinium-based contrast agents.

The importance and prognostic effect of thyroid hormones in patients with transposition of the great arteries

Objectives: Transposition of the great arteries (TGA) is a rare congenital heart disease that occurs in 3 in 10,000 newborns and is rapidly fatal (90%) within one year if left untreated. The prognosis of this pathology changed after introducing an early arterial switch operation (ASO), while the left ventricle could still adapt to systemic high-pressure conditions. Appropriate regulation of thyroid hormones positively impacts metabolism, cardiac function, and postoperative recovery. Therefore, regular thyroid hormone monitoring and thyroid function monitoring of TGA patients may help to improve the health status and prognosis of this group of postoperative patients. Methods: In our study, 127 patients who underwent ASO at our pediatric cardiac surgery clinic between 01.01.2014 and 18.09.2021 were retrospectively analyzed and included. Among the patients, 43% (n=54) were females, and 57% (n=73) were males. Results: The coronary arteries were normal in 89.7% (n=114) and abnormal in 10.3% (n=13) of the patients. Twenty-one of the patients exited, and mortality was calculated to be 16.5%. There were no significant differences in mortality or thyroid stimulating hormone (TSH), free thyroxine (T4), or free triiodothyronine (T3) values (P=0.674, P=0.345, P=0.478). In our study, in which we investigated the effect of thyroid hormone levels on prognosis in neonatal patients with TGA with normal free T3, T4, and TSH values, we found that TSH levels were greater in the group with advanced aortic regurgitation and exitus, although the effect of thyroid hormones on postoperative results was not statistically significant. Conclusions: Congenital hypothyroidism is a common disease with cardiac effects. During the neonatal period, this disease may conceal itself. Careful, expert clinical follow-up and clinical trials are crucial to improve outcomes in the surgical treatment of transposition of the great arteries, a complex congenital heart disease.

Automatic pipeline for segmentation of LV myocardium on quantitative MR T1 maps using deep learning model and computation of radial T1 and ECV values.

Native T1 mapping is a non-invasive technique used for early detection of diffused myocardial abnormalities, and it provides baseline tissue characterization. Post-contrast T1 mapping enhances tissue differentiation, enables extracellular volume (ECV) calculation, and improves myocardial viability assessment. Accurate and precise segmenting of the left ventricular (LV) myocardium on T1 maps is crucial for assessing myocardial tissue characteristics and diagnosing cardiovascular diseases (CVD). This study presents a deep learning (DL)-based pipeline for automatically segmenting LV myocardium on T1 maps and automatic computation of radial T1 and ECV values. The study employs a multicentric dataset consisting of retrospective multiparametric MRI data of 332 subjects to develop and assess the performance of the proposed method. The study compared DL architectures U-Net and Deep Res U-Net for LV myocardium segmentation, which achieved a dice similarity coefficient of 0.84 ±0.43 and 0.85 ±0.03, respectively. The dice similarity coefficients computed for radial sub-segmentation of the LV myocardium on basal, mid-cavity, and apical slices were 0.77 ±0.21, 0.81 ±0.17, and 0.61 ±0.14, respectively. The t-test performed between ground truth vs. predicted values of native T1, post-contrast T1, and ECV showed no statistically significant difference (p> 0.05) for any of the radial sub-segments. The proposed DL method leverages the use of quantitative T1 maps for automatic LV myocardium segmentation and accurately computing radial T1 and ECV values, highlighting its potential for assisting radiologists in objective cardiac assessment and, hence, in CVD diagnostics.

T1 relaxation and axon fibre configuration in human white matter.

Understanding the effects of white matter (WM) axon fibre microstructure on T1 relaxation is important for neuroimaging. Here, we have studied the interrelationship between T1 and axon fibre configurations at 3T and 7T. T1 and S0 (=signal intensity at zero TI) were computed from MP2RAGE images acquired with six inversion recovery times. Multishell diffusion MRI images were analysed for fractional anisotropy (FA); MD; V1; the volume fractions for the first (f1), second (f2) and third (f3) fibre configuration; and fibre density cross-section images for the first (fdc1), second (fdc2) and third (fdc3) fibres. T1 values were plotted as a function of FA, f1, f2, f3, fdc1, fdc2 and fdc3 to examine interrelationships between the longitudinal relaxation and the diffusion MRI microstructural measures. T1 values decreased with increasing FA, f1 and f2 in a nonlinear fashion. At low FA values (from 0.2 to 0.4), a steep shortening of T1 was followed by a shallow shortening by 6%-10% at both fields. The steep shortening was associated with decreasing S0 and MD. T1 also decreased with increasing fdc1 values in a nonlinear fashion. Instead, only a small T1 change as a function of either f3 or fdc3 was observed. In WM areas selected by fdc1 only masks, T1 was shorter than in those with fdc2/fdc3. In WM areas with high single fibre populations, as delineated by f1/fdc1 masks, T1 was shorter than in tissue with high complex fibre configurations, as segmented by f2/fdc2 or f3/fdc3 masks. T1 differences between these WM areas are attributable to combined effects by T1 anisotropy and lowered FA. The current data show strong interrelationships between T1, axon fibre configuration and orientation in healthy WM. It is concluded that diffusion MRI microstructural measures are essential in the effort to interpret quantitative T1 images in terms of tissue state in health and disease.

Predicting efficacy of neoadjuvant chemotherapy in breast cancer patients with synthetic magnetic resonance imaging method MAGiC: An observational cohort study

ObjectiveMAGnetic resonance Imaging Compilation (MAGiC) is typical method of synthetic magnetic resonance imaging (MRI). The present aimed to investigate the role of MAGiC parameters of relaxation time (T1), transverse relaxation time (T2) and proton density (PD) to predict the treatment efficacy of breast cancer patients after neoadjuvant chemotherapy (NAC). MethodsThe present prospective cohort study enrolled 120 breast cancer patients who received NAC during 2021–2023. Demographic data and clinical characteristics including tumor node metastasis (TNM) stage, pathological type, molecular classification and lymph node metastasis were collected. The levels of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2) were measured. Patients were divided by treatment efficacy using the Miller-Payne grading as partial pathological response (pPR) group and pathological complete response (pCR). The values of MAGiC parameters of longitudinal T1, T2, and PD values were recorded. ResultsIn all 120 patients, 73 (60.83%) cases were with pPR and 47 (39.17%) cases were with pCR after treatment. T2 values were markedly lower in pPR patients compared with pCR patients. However, no significant difference was found for T1 and PD values. No significant correlation was observed between any of MAGiC parameters and HER-2, ER or PR. ROC curve showed T2 could be used for prediction of pPR with AUC 0.780. Lymph node metastasis and low levels of T2 were found as independent risk factors for pPR after treatment. ConclusionThe T2 value parameter from MAGiC is an independent risk factor for pPR following NAC in breast cancer patients, suggesting its potential as a biomarker for predicting treatment efficacy.

Investigation of the thyroid function in end-stage renal failure disease in a Baquba teaching hospital/Diyala governorate - Iraq

Renal failure is the inability of the kidneys to excrete nitrogenous waste products, resulting in their retention in the bloodstream. Several correlations exist between renal and thyroid functions; however, end-stage renal failure is unlikely to be influenced by thyroid hormone function and is connected to a higher prevalence of hypothyroidism. The purpose of this study is to ascertain how thyroid status and renal function relate to renal failure patients. Serum creatinine and urea levels were tested in 50 healthy persons and 100 patients with renal failure illness. The acquired data showed that, in comparison to the control group, the average levels of creatinine and urea were significantly higher. The sick group recorded (122.98 mg/dL and 6.55 mg/dL) and (28.38 mg/dL and 0.75 mg/dL) in comparison to the control group, which has urea and creatinine values within the virtually normal range, respectively. In contrast, TSH levels showed no significant differences and have values within the normal range of TSH values, with 2.33 mIU/L for the experimental group and 2.0 mIU/L for the control group. In contrast, T4 values of the experimental group showed significantly lower levels than the control group, with 83.42 ng/dL compared to 103.77 ng/dL. T3 values, however, showed no significant changes and remained within the normal range of 1.75 to 1.64 nmol/L. In addition, the results demonstrated significant differences in the mean levels of anti-TPO, anti-Tg, and anti-TSHR antibodies. The anti-Tg showed a significant decrease in mean values, which were 28.89 IU/ml and 79.49 IU/ml compared to the control group ranges of 34.41 and 86.68 IU/mL. Finally, anti-TSHR showed a significant increase in the mean, which was 1.24 IU/L compared to 1.18 IU/L in the control group.

Myocardial Fibrosis in Young and Veteran Athletes: Evidence from a Systematic Review of the Current Literature.

Background: Exercise is associated with several cardiac adaptations that can enhance one's cardiac output and allow one to sustain a higher level of oxygen demand for prolonged periods. However, adverse cardiac remodelling, such as myocardial fibrosis, has been identified in athletes engaging in long-term endurance exercise. Cardiac magnetic resonance (CMR) imaging is considered the noninvasive gold standard for its detection and quantification. This review seeks to highlight factors that contribute to the development of myocardial fibrosis in athletes and provide insights into the assessment and interpretation of myocardial fibrosis in athletes. Methods: A literature search was performed using the PubMed/Medline database and Google Scholar for publications that assessed myocardial fibrosis in athletes using CMR. Results: A total of 21 studies involving 1642 endurance athletes were included in the analysis, and myocardial fibrosis was found in 378 of 1595 athletes. A higher prevalence was seen in athletes with cardiac remodelling compared to control subjects (23.7 vs. 3.3%, p < 0.001). Similarly, we found that young endurance athletes had a significantly higher prevalence than veteran athletes (27.7 vs. 19.9%, p < 0.001), while male and female athletes were similar (19.7 vs. 16.4%, p = 0.207). Major myocardial fibrosis (nonischaemic and ischaemic patterns) was predominately observed in veteran athletes, particularly in males and infrequently in young athletes. The right ventricular insertion point was the most common fibrosis location, occurring in the majority of female (96%) and young athletes (84%). Myocardial native T1 values were significantly lower in athletes at 1.5 T (p < 0.001) and 3 T (p = 0.004), although they had similar extracellular volume values to those of control groups. Conclusions: The development of myocardial fibrosis in athletes appears to be a multifactorial process, with genetics, hormones, the exercise dose, and an adverse cardiovascular risk profile playing key roles. Major myocardial fibrosis is not a benign finding and warrants a comprehensive evaluation and follow-up regarding potential cardiac disease.

Myocardial hypertrophy: the differentiation of uremic, hypertensive, and hypertrophic cardiomyopathies by cardiac MRI

ObjectivesTo apply cardiac magnetic resonance imaging (CMR) for detailed myocardial characterization in uremic cardiomyopathy (UC), hypertensive cardiomyopathy (HTN), and hypertrophic cardiomyopathy (HCM) aiming to enrich the understanding of UC’s etiology and further support the development of therapeutic strategies.MethodsA total of 152 patients (age: 49.2 ± 9.9 years; 65.8% male) underwent routine CMR from June 2016 to March 2023. Retrospectively, 53 patients with UC, 39 patients with HTN, 30 patients with HCM, and 30 healthy controls were included. Functional analysis, feature tracking of the left ventricle and left atrium, and myocardial T1, T2, and T2* mapping were performed. Statistical analysis included Pearson correlation and ROC analysis to define correlations and discriminators between groups.ResultsUC patients demonstrated significantly higher native T1 (p < 0.001 for all) and T2 (p < 0.002 for all) values compared with the other three groups. UC patients revealed higher left atrial reservoir strain rate (p < 0.001 for all) and left atrial conduit strain rate (p < 0.001 for all) absolute values as compared with HTN and HCM patients. A significant correlation between T1 and T2 values in UC patients (r = 0.511, p < 0.001) was found. The combination of T1 values and strain parameters was the best discriminator between UC and HTN patients (AUC = 0.872, 95% CI: 0.801–0.943) and between UC and HCM patients (AUC = 0.840, 95% CI: 0.746–0.934).ConclusionUC reveals distinguishing tissue characteristics as evidenced by T1 and T2 mapping, as well as distinguishing functional strain parameters as compared with other hypertrophic phenotypes such as HTN and HCM.Critical relevance statementThe use of CMR imaging in UC patients offers incremental information to elucidate its complex etiology, contributing to ongoing discourse on effective treatment pathways.Key PointsThis study investigated uremic, hypertensive, and hypertrophic cardiomyopathies using cardiac MRI.UC patients have higher T1 and T2 values and better preserved cardiac function.Combined strain and T1 values distinguish UC from other cardiomyopathies.Graphical

The value of synthetic magnetic resonance imaging in the diagnosis and assessment of prostate cancer aggressiveness.

Synthetic magnetic resonance imaging (SyMRI) is a fast, standardized, and robust novel quantitative technique that has the potential to circumvent the subjectivity of interpretation in prostate multiparametric magnetic resonance imaging (mpMRI) and the limitations of existing MRI quantification techniques. Our study aimed to evaluate the potential utility of SyMRI in the diagnosis and aggressiveness assessment of prostate cancer (PCA). We retrospectively analyzed 309 patients with suspected PCA who had undergone mpMRI and SyMRI, and pathologic results were obtained by biopsy or PCA radical prostatectomy (RP). Pathological types were classified as PCA, benign prostatic hyperplasia (BPH), or peripheral zone (PZ) inflammation. According to the Gleason Score (GS), PCA was divided into groups of intermediate-to-high risk (GS ≥4+3) and low-risk (GS ≤3+4). Patients with biopsy-confirmed low-risk PCA were further divided into upgraded and nonupgraded groups based on the GS changes of the RP results. The values of the apparent diffusion coefficient (ADC), T1, T2 and proton density (PD) of these lesions were measured on ADC and SyMRI parameter maps by two physicians; these values were compared between PCA and BPH or inflammation, between the intermediate-to-high-risk and low-risk PCA groups, and between the upgraded and nonupgraded PCA groups. The risk factors affecting GS grades were identified via univariate analysis. The effects of confounding factors were excluded through multivariate logistic regression analysis, and independent predictive factors were calculated. Subsequently, the ADC+Sy(T2+PD) combined models for predicting PCA risk grade or GS upgrade were constructed through data processing analysis. The diagnostic performance of each parameter and the ADC+Sy(T2+PD) model was analyzed. The calibration curve was calculated by the bootstrapping internal validation method (200 bootstrap resamples). The T1, T2, and PD values of PCA were significantly lower than those of BPH or inflammation (P≤0.001) in both the PZ or transitional zone. Among the 178 patients with PCA, intermediate-to-high-risk PCA group had significantly higher T1, T2, and PD values but lower ADC values compared with the low-risk group (P<0.05), and the diagnostic efficacy of each single parameter was similar (P>0.05). The ADC+Sy(T2+PD) model showed the best performance, with an area under the curve (AUC) 0.110 [AUC =0.818; 95% confidence interval (CI): 0.754-0.872] higher than that of ADC alone (AUC =0.708; 95% CI: 0.635-0.774) (P=0.003). Among the 68 patients initially classified as PCA in the low-risk group by biopsy, PCA in the postoperative upgraded GS group had significantly higher T1, T2, and PD values but lower ADC values than did those in the nonupgraded group (P<0.01). In addition, the ADC+Sy(T2+PD) model better predicted the upgrade of GS, with a significant increase in AUC of 0.204 (AUC =0.947; 95% CI: 0.864-0.987) compared with ADC alone (AUC =0.743; 95% CI: 0.622-0.841) (P<0.001). Quantitative parameters (T1, T2, and PD) derived from SyMRI can help differentiate PCA from non-PCA. Combining SyMRI parameters with ADC significantly improved the ability to differentiate between intermediate-to-high risk PCA from low-risk PCA and could predict the upgrade of low-risk PCA as confirmed by biopsy.

Intracortical myelin across laminae in adult individuals with 47,XXX: a 7 Tesla MRI study.

47,XXX (Triple X syndrome) is a sex chromosome aneuploidy characterized by the presence of a supernumerary X chromosome in affected females and is associated with a variable cognitive, behavioral, and psychiatric phenotype. The effect of a supernumerary X chromosome in affected females on intracortical microstructure is currently unknown. Therefore, we conducted 7 Tesla structural MRI and compared T1 (ms), as a proxy for intracortical myelin (ICM), across laminae of 21 adult women with 47,XXX and 22 age-matched typically developing females using laminar analyses. Relationships between phenotypic traits and T1 values in 47,XXX were also investigated. Adults with 47,XXX showed higher bilateral T1 across supragranular laminae in the banks of the superior temporal sulcus, and in the right inferior temporal gyrus, suggesting decreases of ICM primarily within the temporal cortex in 47,XXX. Higher social functioning in 47,XXX was related to larger inferior temporal gyrus ICM content. Our findings indicate an effect of a supernumerary X chromosome in adult-aged women on ICM across supragranular laminae within the temporal cortex. These findings provide insight into the role of X chromosome dosage on ICM across laminae. Future research is warranted to further explore the functional significance of altered ICM across laminae in 47,XXX.

Significant reduction of anisotropy in stress relaxation aging and mechanical properties improvement for 2195 Al-Cu-Li alloy subjected to plastic loading

Although the plastic loading can enhance creep deformation and yield strength, the anisotropic Stress Relaxation Aging (SRA) behavior and mechanism under plastic loading remain unclear, which presents a significant challenge in accurately shaping aluminum alloy panels. In this study, the SRA behavior of 2195-T4 Al-Cu-Li alloys were thoroughly studied under initial loading stresses within the elastic (210/250 MPa) and plastic (380/420 MPa) ranges at 180 ℃ by stress relaxation and tensile tests as well as microstructure characterization. The findings reveal that compared with those under elastic loadings, in-plane anisotropy (IPA) values of the stress relaxation amount, yield strength and fracture elongation under plastic loadings are reduced by 60%-80%, 70%-90% and 72%-89%, respectively. Similarly, IPA values of precipitate size in grains and Precipitation-Free Zones (PFZ) width at grain boundaries under plastic loading decrease by 31.4% and 94.4% respectively. These results indicate plastic loading significantly weakens the anisotropic SRA behavior, owing to numerous uniformly distributed fine T1 phases and small IPA values of both T1 precipitates size and PFZ width in various loading directions. Compared with those of elastic loading-aged alloys, yield strength of plastic loading-aged alloys shows high strength-ductility because of the combined effect of closely dispersed fine T1 precipitates, narrowed PFZ and numerous sheared and rotated T1 phases at different locations during tensile process. The uniformly distributed larger Kernel Average Misorientation (KAM) and Schmidt factor values of the plastic loading-aged alloy, as well as the cross-slip generated, also help to enhance the strength and ductility of the alloy.

Association between cardiovascular inflammation and alterations in immune system induced by HIV infection detected on [18F]FDG PET/MRI

ObjectiveTo assess by [18F]FDG PET/MR the biomarkers of HIV-induced inflammation at baseline and 1 year post-antiretroviral therapy (ART). MethodsProspective study, 14 patients, newly diagnosed HIV-positive, asymptomatic.[18F]FDG PET/MRI (PET/MR-3.0T, Signa.GE) whole body and heart was performed, baseline and 1 year post-ART.Qualitative vascular assessment (hepatic reference). Quantitative assessment (SUVmax) of the whole body. T1 and T2 value estimation in 16 myocardial segments. ResultsBaseline CMR showed in 3 (21.4%) a decreased LVEF, normalising post-TAR. Fibrosis was ruled out (T1), with no signs of myocardial oedema (T2) at baseline or post-TAR.Four (28.6%) showed baseline vascular [18F]FDG uptake, two in ascending thoracic aorta and two in ascending and descending thoracic aorta, normalising post-TAR.All (100%) showed basal lymph-nodes activity; supra (n:14) and infradiaphragmatic (n:13), laterocervical (n:14) and inguinal (n:13), with variable number of territories (9 patients >6;64.3%). Post-ART, 7 patients (50%) showed resolution and the other 7 reduction in extension (0 patients >5): 7 supra (100%) and 2 infradiaphragmatic (28.6%), 5 in the axilla and 2 in the groin.All (100%) had persistent basal adenoid uptake post-ART, 9 (64.3%) splenic all resolved post-ART and 7 (50.5%) gastric, persistent 3 post-ART. ConclusionsCardiovascular biomarkers by [18F]FDG PET/MR have shown baseline 28.6% of patients with large vessel activity and 21.4% with low LVEF, normalising post-ART.Inflammatory/immune biomarkers showed baseline activity in 100% of lymph-nodes, 100% adenoids, 64.3% splenic and 50.5% gastric. Post-TAR the reduction was 50% lymph-nodes, 0% adenoid, 100% splenic and 57.1% gastric.

Native T1 Values are Elevated in Patients With Extra-Cardiac Sarcoid Without Conventional MRI Evidence of Cardiac Involvement

Native T1 Values are Elevated in Patients With Extra-Cardiac Sarcoid Without Conventional MRI Evidence of Cardiac Involvement

Effect of Dietary Zinc on the Antioxidant Parameters of Juvenile Common Carp (Cyprinus carpio)

Zinc (Zn) is an essential micro mineral needed for the proper growth and immune function of fish. This investigation was designed to examine the antioxidant role of a fortified diet with different Zn levels in the muscle and liver tissues of carp fry. A four-iso-nitrogen (35% crude protein) practical diet was produced that included graded levels of dietary zinc sulphate as a nutritional zinc resource in the fundamental diet supplemented with increased zinc levels (T1, control, 85 mg Zn kg-1, T2 105 mg Zn kg-1, T3, 125 mg Zn kg-1 and T4, 145 mg Zn kg-1). Even though the SOD and CAT analysis results did not show a linear increase in the increasing Zn ratio in the diets, higher values were obtained compared to the control groups. SOD highest values in T3 for the liver (0.713 ± 0.220 U/ml) and T1 for muscle (0.751 ± 0.144 U/ml), CAT values were highest in T2 for the liver (0.849 ± 0.115 nmol/dk/m) and T2 for muscle (1.059 ± 0.148 nmol/dk/m) was obtained. MDA values were completely higher for the muscle than for the control group, and for the liver, a lower value was obtained in the T2 trial group than in the control group (1.671 ± 0.230 µM). The results of the study showed that Zn contributed significantly to the nutrition of carp fish. It can be concluded that the findings of SOD and CAT analysis endorse the positive contributions of using 105 mg Zn in the diets to promote the antioxidant defense of juvenile carp fish.

Impact of undersampling on preclinical lung T2* mapping with 3D radial UTE MRI at 7 T

Lung diseases are almost invariably heterogeneous and progressive, making it imperative to capture temporally and spatially explicit information to understand the disease initiation and progression. Imaging the lung with MRI—particularly in the preclinical setting—has historically been challenging because of relatively low lung tissue density, rapid cardiac and respiratory motion, and rapid transverse (T2*) relaxation. These limitations can largely be mitigated using ultrashort-echo-time (UTE) sequences, which are intrinsically robust to motion and avoid significant T2* decay. A significant disadvantage of common radial UTE sequences is that they require inefficient, center-out k-space sampling, resulting in long acquisition times relative to conventional Cartesian sequences. Therefore, pulmonary images acquired with radial UTE are often undersampled to reduce acquisition time. However, undersampling reduces image SNR, introduces image artifacts, and degrades true image resolution. The level of undersampling is further increased if offline gating techniques like retrospective gating are employed, because only a portion (∼40–50%) of the data is used in the final image reconstruction. Here, we explore the impact of undersampling on SNR and T2* mapping in mouse lung imaging using simulation and in-vivo data. Increased scatter in both metrics was noticeable at around 50% sampling. Parenchymal apparent SNR only decreased slightly (average decrease ∼ 1.4) with as little as 10% sampling. Apparent T2* remained similar across undersampling levels, but it became significantly increased (p < 0.05) below 80% sampling. These trends suggest that undersampling can generate quantifiable, but moderate changes in the apparent value of T2*. Moreover, these approaches to assess the impact of undersampling are straightforward to implement and can readily be expanded to assess the quantitative impact of other MR acquisition and reconstruction parameters.