NiMOF-Derived MoSe2/NiSe Hollow Nanoflower Structures as Electrocatalysts for Hydrogen Evolution Reaction in Alkaline Medium.

Metal-organic frameworks (MOFs) are crystalline porous materials for storage and energy conversion applications with three-dimensional pore structure, high porosity, and specific surface area, which are widely utilized in electrocatalysis. Herein, MoSe2/NiSe composites were synthesized by selenization reaction using NiMOF as the precursor. The composites were hollow nanoflower structures with a synergistic effect between MoSe2 and NiSe to promote rapid electron transfer, which exhibited good hydrogen evolution reaction performance in an alkaline medium. At a current density of 10 mA/cm2, the HER overpotential reaches 80 mV, the Tafel slope is 33.86 mV/dec, and the material has good stability, with polarization curves remaining essentially unchanged after 3000 cycles. These results indicate that the method has a promising application in the preparation of efficient and sustainable catalysts for hydrogen production in alkaline medium.

Clinicopathological significance of cancer stem cell marker CD44/SOX2 in esophageal squamous cell carcinoma (ESCC) patients and construction of a nomogram to predict overall survival.

Background: Esophageal squamous cell carcinoma (ESCC), a prevalent malignancy within the upper gastrointestinal system, is characterized by its unfavorable prognosis and the absence of specific indicators for outcome prediction and high-risk case identification. In our research, we examined the expression levels of cancer stem cells (CSCs), markers CD44/SOX2 in ESCC, scrutinized their association with clinicopathological parameters, and developed a predictive nomogram model. This model, which incorporates CD44/SOX2, aims to forecast the overall survival (OS) of patients afflicted with ESCC. Methods: Immunohistochemistry was utilized to detect the expression levels of CD44 and SOX2 in both cancerous and paracancerous tissues of 68 patients with ESCC. The correlation between CD44/SOX2 expression and clinicopathological parameters was subsequently analyzed. Factors impacting the prognosis of ESCC patients were assessed through univariate and multivariate Cox regression analyses. Leveraging the results of these multivariate regression analyses, a nomogram prognostic model was established to provide individualized predictions of ESCC patient survival outcomes. The predictive accuracy of the nomogram prognostic model was evaluated using the consistency index (C-index) and calibration curves. Results: The expression levels of CD44 were markedly elevated in the tumor tissues of ESCC patients. Similarly, SOX2 was significantly overexpressed in the tumor tissues of ESCC patients. The positive expression of SOX2 in ESCC demonstrated a strong correlation with both the pathological T-stage and the presence of carcinoembryonic antigen. CD44 and SOX2 co-positive expression was significantly associated with the pathological T-stage and tumor node metastasis (TNM) stage. Furthermore, ESCC patients exhibiting CD44-positive expression in their tumor tissue generally had a more adverse prognosis. The co-expression of CD44 and SOX2 resulted in a grimmer prognosis compared to patients with other combinations. Multivariate Cox regression analysis identified the co-expression of CD44 and SOX2, the pathological T-stage, and lymph node metastasis as independent prognostic indicators for ESCC patients. The three identified variables were subsequently incorporated into a nomogram for predicting OS. The C-index of the measurement model and the area under the curve of the subjects' work characteristics showed good individual prediction. This prognostic model stratified patients into low- and high-risk categories. Analysis revealed that the 5-year OS rate was significantly higher in the low-risk group compared to the high-risk group. Conclusions: Elevated CD44 levels, indicative of CSC presence, are intimately linked with the oncogenesis of ESCC and are strongly predictive of unfavorable patient outcomes. Concurrently, the SOX2 gene exhibits a heightened expression in ESCC, markedly accelerating tumor progression and fostering more extensive disease infiltration. The co-expression of CD44 and SOX2 correlates significantly with ESCC patient prognosis, serving as a reliable, independent prognostic marker. Our constructed nomogram, incorporating CD44/SOX2 expression, enhances the prediction of OS and facilitates risk stratification in ESCC patients.

Expression and Clinicopathological Significance of Extracellular Matrix Remodeling Markers in Esophageal Squamous Carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a common malignancy of the gastrointestinal tract with a single therapeutic option and a lack of effective clinical therapeutic biomarkers. Extracellular matrix (ECM) remodeling plays a pro-carcinogenic role in a variety of malignancies, but its role in esophageal squamous carcinoma remains to be elucidated. In this study, we examined the expression levels of ECM remodeling markers in 71 pairs of esophageal squamous carcinoma tissues and normal tissues adjacent to the carcinoma using immunohistochemical staining, and analyzed their relationship with clinicopathological features and prognosis. The results suggested that extracellular matrix remodeling markers (integrin αV, fibronectin, MMP9) were abnormally highly expressed in esophageal squamous carcinoma tissues. There was a statistically significant difference between the positive expression of ECM remodeling and the TNM stage of esophageal squamous carcinoma, and there was no statistically significant correlation with age, gender and carcinoembryonic antigen expression, differentiation degree, T stage, and lymph node metastasis. Overall survival rate and overall survival time were significantly lower in patients with positive ECM remodeling expression, which was an independent risk factor for poor prognosisof esophageal squamous carcinoma.

Motion-robust free-running volumetric cardiovascular MRI.

PURPOSE: To present and assess an outlier mitigation method that makes free-running volumetric cardiovascular MRI (CMR) more robust to motion. METHODS: The proposed method, called compressive recovery with outlier rejection (CORe), models outliers in the measured data as an additive auxiliary variable. We enforce MR physics-guided group sparsity on the auxiliary variable, and jointly estimate it along with the image using an iterative algorithm. For evaluation, CORe is first compared to traditional compressed sensing (CS), robust regression (RR), and an existing outlier rejection method using two simulation studies. Then, CORe is compared to CS using seven three-dimensional (3D) cine, 12 rest four-dimensional (4D) flow, and eight stress 4D flow imaging datasets. RESULTS: Our simulation studies show that CORe outperforms CS, RR, and the existing outlier rejection method in terms of normalized mean square error and structural similarity index across 55 different realizations. The expert reader evaluation of 3D cine images demonstrates that CORe is more effective in suppressing artifacts while maintaining or improving image sharpness. Finally, 4D flow images show that CORe yields more reliable and consistent flow measurements, especially in the presence of involuntary subject motion or exercise stress. CONCLUSION: An outlier rejection method is presented and tested using simulated and measured data. This method can help suppress motion artifacts in a wide range of free-running CMR applications.

Cardiac and respiratory motion extraction for MRI using pilot tone-a patient study.

This study aims to evaluate the accuracy and reliability of the cardiac and respiratory signals extracted from Pilot Tone (PT) in patients clinically referred for cardiovascular MRI. Twenty-three patients were scanned under free-breathing conditions using a balanced steady-state free-precession real-time (RT) cine sequence on a 1.5T scanner. The PT signal was generated by a built-in PT transmitter integrated within the body array coil, and retrospectively processed to extract respiratory and cardiac signals. For comparison, ECG and BioMatrix (BM) respiratory sensor signals were also synchronously recorded. To assess the performances of PT, ECG, and BM, cardiac and respiratory signals extracted from the RT cine images were used as the ground truth. The respiratory motion extracted from PT correlated positively with the image-derived respiratory signal in all cases and showed a stronger correlation (absolute coefficient: 0.95 ± 0.09) than BM (0.72 ± 0.24). For the cardiac signal, PT trigger jitter (standard deviation of PT trigger locations relative to ECG triggers) ranged from 6.6 to 83.3 ms, with a median of 21.8 ms. The mean absolute difference between the PT and corresponding ECG cardiac cycle duration was less than 5% of the average ECG RR interval for 21 out of 23 patients. We did not observe a significant linear dependence (p > 0.28) of PT delay and PT jitter on the patients' BMI or cardiac cycle duration. This study demonstrates the potential of PT to monitor both respiratory and cardiac motion in patients clinically referred for cardiovascular MRI.

The effect of Maslow's theory-based case management model on the care of stroke patients.

OBJECTIVE: To explore the application value of a case management model based on Maslow's theory in stroke patients. METHODS: A total of 136 stroke patients admitted in the Number Two Hospital of Baoding from November 2019 to January 2023 were selected retrospectively. Based on the nursing measurements, 68 patients receiving conventional care were assigned to the control group, and 68 patients receiving case management nursing based on Maslow's theory were assigned to the observation group. The basic information of two groups of patients were compared; besides, the neurological function, daily living ability (ADL), quality of life (Stroke Impact Scale, SIS), self-care ability, functional outcomes (Modified Rankin Scale, mRS), complications, and nursing satisfaction of two groups of patients were also compared before and after nursing care. RESULTS: After nursing, the observation group showed more significant improvements in neurological function, daily living ability, quality of life, self-care ability, and functional outcomes (all P<0.05), but lower incidence in complications (P<0.05) than the control group. In addition, the patient satisfaction rate was significantly higher in the observation group than that in the control group. CONCLUSION: Case management guidance based on Maslow's theory for stroke patients can improve patient rehabilitation outcomes and satisfaction with care. The model achieves continuity of information, resources, and personnel for stroke patients after discharge, coordinates multidisciplinary management, and ensures the rational utilization of medical resources. It is an effective way of health care and worthy of clinical promotion.

Clinical effect and safety analysis of long-round needle usage in treating cervical spondylotic radiotelegraphy and its effect on pain and functional recovery.

BACKGROUND: Long-round needle usage can treat muscular pain, but there is little research on cervical spondylotic radiculopathy (CSR). OBJECTIVE: To explore the efficacy and safety of long-round needle usage in treating CSR. METHODS: Ninety-eight patients with CSR were randomly divided into control and observation groups. They were treated with filiform needles and long-round needles, respectively. The therapeutic effect, safety, inflammatory factors and neck dysfunction index (NDI), McGill pain questionnaire (MPQ) and Generic Quality of Life Inventory-74 (GQOL-74) scores were compared between the two groups. RESULTS: After treatment, the effective rate and safety of the observation group were better than those of the control group. The NDI and MPQ scores in the observation group were significantly lower than those in the control group, and the GQOL-74 score was higher than that in the control group. The level of interleukin-8 in the observation group was significantly lower than that in the control group, and the level of interleukin-10 was significantly higher than that in the control group. CONCLUSIONS: Long-round needle therapy has a good effect on patients with CSR, which can safely improve the quality of life of patients with mild local inflammatory damage.

Application of role reversal and standardized patient simulation (SPS) in the training of new nurses.

PURPOSE: To explore the effect of role reversal and standardized patient simulation on the training of new nurses. METHOD: This study was conducted in a territory hospital in China between August 2021 and August 2022. The selected staff were all newly recruited and trained nurses, with a total of 58 cases. This study is a randomised controlled trial. The selected nurses were randomly divided into two groups. One group of 29 nurses (the control group) received routine training and assessment; the other group (the experimental group) was given role reversal combined with a standardized vertebral patient training examination. The implementation effects of different training and assessment methods were compared and analysed. RESULTS: Before the training, the core competence scores of nurses in the two groups were lower, and there was no significant data difference (P > 0.05). After training, the core competence scores of nurses were improved, and the score of nurses in the experimental group was 165.49 ± 22.34. The difference was statistically significant when compared with the score of nurses in the control group (P < 0.05), indicating that nurses in the experimental group had better abilities. At the same time, the satisfaction of the two groups of nurses with the training was 96.55% (experimental group) and 75.86% (control group), and the difference in data was significant (P < 0.05). The satisfaction of the experimental group of nurses was higher, and the training effect was better. CONCLUSION: In the training of new nurses, the combined application of role interchange and standardized patient training and assessment methods has significant effects, which can improve the core competency of nurses and improve the training satisfaction of nurses, which is significant.

Building a comprehensive cardiovascular magnetic resonance exam on a commercial 0.55 T system: A pictorial essay on potential applications.

Background: Contemporary advances in low-field magnetic resonance imaging systems can potentially widen access to cardiovascular magnetic resonance (CMR) imaging. We present our initial experience in building a comprehensive CMR protocol on a commercial 0.55 T system with a gradient performance of 26 mT/m amplitude and 45 T/m/s slew rate. To achieve sufficient image quality, we adapted standard imaging techniques when possible, and implemented compressed-sensing (CS) based techniques when needed in an effort to compensate for the inherently low signal-to-noise ratio at lower field strength. Methods: A prototype CMR exam was built on an 80 cm, ultra-wide bore commercial 0.55 T MR system. Implementation of all components aimed to overcome the inherently lower signal of low-field and the relatively longer echo and repetition times owing to the slower gradients. CS-based breath-held and real-time cine imaging was built utilizing high acceleration rates to meet nominal spatial and temporal resolution recommendations. Similarly, CS 2D phase-contrast cine was implemented for flow. Dark-blood turbo spin echo sequences with deep learning based denoising were implemented for morphology assessment. Magnetization-prepared single-shot myocardial mapping techniques incorporated additional source images. CS-based dynamic contrast-enhanced imaging was implemented for myocardial perfusion and 3D MR angiography. Non-contrast 3D MR angiography was built with electrocardiogram-triggered, navigator-gated magnetization-prepared methods. Late gadolinium enhanced (LGE) tissue characterization methods included breath-held segmented and free-breathing single-shot imaging with motion correction and averaging using an increased number of source images. Proof-of-concept was demonstrated through porcine infarct model, healthy volunteer, and patient scans. Results: Reasonable image quality was demonstrated for cardiovascular structure, function, flow, and LGE assessment. Low-field afforded utilization of higher flip angles for cine and MR angiography. CS-based techniques were able to overcome gradient speed limitations and meet spatial and temporal resolution recommendations with imaging times comparable to higher performance scanners. Tissue mapping and perfusion imaging require further development. Conclusion: We implemented cardiac applications demonstrating the potential for comprehensive CMR on a novel commercial 0.55 T system. Further development and validation studies are needed before this technology can be applied clinically.

Phosphorylation of AKT by lysyl oxidase-like 2 activates the PI3K/AKT signaling pathway to promote proliferation, invasion and metastasis in esophageal squamous carcinoma.

OBJECTIVE: Esophageal squamous cell carcinoma (ESCC) is a common and aggressive malignancy of the gastrointestinal tract for which therapeutic options are scarce. This study screens for LOXL2, a key gene in ESCC, and explains the molecular mechanism by which it promotes the progression of ESCC. METHODS: Immunohistochemical staining was performed to detect the expression level of LOXL2 in ESCC tissues and paraneoplastic tissues. CCK-8 and Transwell assays were performed to assess the effects of LOXL2 knockdown and overexpression on the proliferation, apoptosis, migration and invasion ability of ESCC cells. High-throughput sequencing analysis screens for molecular mechanisms of action by which LOXL2 promotes ESCC progression. Western blotting and qRT-PCR were used to determine the expression levels of relevant markers. RESULTS: LOXL2 is positively expressed in ESCC and highly correlated with poor prognosis. Silencing LOXL2 significantly inhibited the proliferation, migration and invasive ability of ESCC cells, whereas overexpression showed the opposite phenotype. High-throughput sequencing suggested that LOXL2-associated differentially expressed genes were highly enriched in the PI3K/AKT signaling pathway. In vitro cellular assays confirmed that silencing LOXL2 significantly reduced PI3K, p-AKTThr308 and p-AKTSer473 gene and protein expression levels, while overexpression increased all three gene and protein levels, while AKT gene and protein expression levels were not significantly different. CONCLUSION: This study found that LOXL2 may regulate the PI3K/AKT signaling pathway and exert protumor effects on ESCC cells through phosphorylation of AKT. LOXL2 may be a key clinical warning biomarker or therapeutic target for ESCC.

Clinical study on flipped classroom and mind map in newly recruited nurses' pre-job training.

BACKGROUND: Traditional pre-job training mainly provides theoretical lectures and operational skill training for new nurses. However, it has a single teaching method, lacks in comprehensiveness and flexibility, and has unsatisfactory teaching effects. The purpose of this article is to evaluate the influence of the flipped classroom and mind map in the pre-job training of newly recruited nurses. METHOD: A total of 92 nurses newly recruited in 2019 were included in the present study and randomly divided into two groups: the intervention group and the control group (n = 46, each). An ordinary training program was applied in the control group, and the flipped classroom + mind map training method was applied in the intervention group. All the new nurses were evaluated using the autonomous learning ability scale before and after pre-job training. RESULTS: The results of the present study showed that before the pre-job training, the total scores of independent learning ability, learning motivation, self-management ability, learning cooperation ability and information quality of nursing staff were similar in the control group and the intervention group; the differences were not statistically significant (P > 0.05). After the application of different training methods, the total score of independent learning ability (84.95 ± 5.146 vs. 66.73 ± 11.213), learning motivation (28.65 ± 3.198 vs. 22.78 ± 5.995), self-management ability (24.97 ± 3.586 vs. 17.89 ± 4.153), learning and cooperation ability (14.391 ± 1.584 vs. 12.17 ± 2.584) and information quality score (16.93 ± 1.306 vs. 13.89 ± 2.651) in the intervention group were significantly higher than in the control group; the differences were statistically significant (P < 0.05). CONCLUSION: The flipped classroom + mind map training method can effectively improve the autonomous learning ability of newly recruited nurses.

Ensuring respiratory phase consistency to improve cardiac function quantification in real-time CMR.

PURPOSE: To develop an automatic method for selecting heartbeats with consistent respiratory phase to improve accuracy of cardiac function quantification in real-time (RT) cardiac MRI. METHODS: The respiratory signal is extracted by a principal component analysis method from RT cine images. Then, a two-step procedure is used to determine the directionality (sign) of the respiratory signal. With the motion in a manually selected region-of-interest as a reference, the quality of the extracted respiratory signal is assessed using multislice RT cine data from 11 volunteers and 10 patients. In addition, the impact of selecting heartbeats with consistent respiratory phase on the cardiac function quantification is evaluated. RESULTS: The extracted respiratory signal using the proposed method exhibits a high, positive correlation with the reference in all cases and is more robust compared to a recently proposed method. Also, for right ventricular function quantification, selecting heartbeats at expiratory position improves agreement between RT cine and breath-held reference. CONCLUSION: The proposed method enables fully automatic extraction and directionality determinations of respiratory signal from RT cardiac cine images, allowing accurate cardiac function quantification.

Fully self-gated whole-heart 4D flow imaging from a 5-minute scan.

PURPOSE: To develop and validate an acquisition and processing technique that enables fully self-gated 4D flow imaging with whole-heart coverage in a fixed 5-minute scan. THEORY AND METHODS: The data are acquired continuously using Cartesian sampling and sorted into respiratory and cardiac bins using the self-gating signal. The reconstruction is performed using a recently proposed Bayesian method called ReVEAL4D. ReVEAL4D is validated using data from 8 healthy volunteers and 2 patients and compared with compressed sensing technique, L1-SENSE. RESULTS: Healthy subjects-Compared with 2D phase-contrast MRI (2D-PC), flow quantification from ReVEAL4D shows no significant bias. In contrast, the peak velocity and peak flow rate for L1-SENSE are significantly underestimated. Compared with traditional parallel MRI-based 4D flow imaging, ReVEAL4D demonstrates small but significant biases in net flow and peak flow rate, with no significant bias in peak velocity. All 3 indices are significantly and more markedly underestimated by L1-SENSE. Patients-Flow quantification from ReVEAL4D agrees well with the 2D-PC reference. In contrast, L1-SENSE markedly underestimated peak velocity. CONCLUSIONS: The combination of highly accelerated 5-minute Cartesian acquisition, self-gating, and ReVEAL4D enables whole-heart 4D flow imaging with accurate flow quantification.

Hierarchically porous hydrangea-like In2S3/In2O3 heterostructures for enhanced photocatalytic hydrogen evolution.

Semiconductor-based photocatalytic hydrogen evolution is considered to be a promising and cost-effective approach to address the environmental issues and energy crisis. It still remains a great challenge to design highly-efficient semiconductor photocatalysts via a facile method. Herein, hierarchically porous hydrangea-like In2S3/In2O3 heterostructures are successfully synthesized via a simple in situ oxidization process. The formed In2S3/In2O3 heterostructures exhibit superior photocatalytic activity to the counterpart In2S3 and In2O3. The boosted photocatalytic performance is ascribed to the formed heterostructures, which greatly facilitate the interfacial charge transfer. Moreover, the formation of hierarchically porous heterostructures increases the number of active sites and improves the permeability, and thus significantly promotes the photocatalytic H2 evolution activity. This work may provide a new insight for designing In2S3-based heterostructures for efficient solar light conversion.

Prospective correction of patient-specific respiratory motion in myocardial T1 and T2 mapping.

PURPOSE: Respiratory motion in cardiovascular MRI presents a challenging problem with many potential solutions. Current approaches require breath-holds, apply retrospective image registration, or significantly increase scan time by respiratory gating. Myocardial T1 and T2 mapping techniques are particularly sensitive to motion as they require multiple source images to be accurately aligned prior to the estimation of tissue relaxation. We propose a patient-specific prospective motion correction (PROCO) strategy that corrects respiratory motion on the fly with the goal of reducing the spatial variation of myocardial parametric mapping techniques. METHODS: A rapid, patient-specific training scan was performed to characterize respiration-induced motion of the heart relative to a diaphragmatic navigator, and a parametric mapping pulse sequence utilized the resulting motion model to prospectively update the scan plane in real-time. Midventricular short-axis T1 and T2 maps were acquired under breath-hold or free-breathing conditions with and without PROCO in 7 healthy volunteers and 3 patients. T1 and T2 were measured in 6 segments and compared to reference standard breath-hold measurements using Bland-Altman analysis. RESULTS: PROCO significantly reduced the spatial variation of parametric maps acquired during free-breathing, producing limits of agreement of -47.16 to 30.98 ms (T1 ) and -1.35 to 4.02 ms (T2 ), compared to -67.77 to 74.34 ms (T1 ) and -2.21 to 5.62 ms (T2 ) for free-breathing acquisition without PROCO. CONCLUSION: Patient-specific respiratory PROCO method significantly reduced the spatial variation of myocardial T1 and T2 mapping, while allowing for 100% efficient free-breathing acquisitions.

Co-delivery of Doxorubicin and Curcumin with Polypeptide Nanocarrier for Synergistic Lymphoma Therapy.

The traditional chemotherapy, including Adriamycin (Doxorubicin, DOX), is widely used and is part of the first-line chemotherapy of invasive B cell lymphoma. DOX is nonselective cytotoxic drug and has many adverse effects, which limit its clinical application in combination with other anti-cancer drugs. Optimization of the delivery system targeting tumor microenvironment could be a feasible approach that may have significant clinical significance. Further, combination of DOX with other anticancer drugs, such as curcumin, can enhance the synergistic effects, possibly through epigenetic mechanisms. Hence, we evaluated the efficacy and toxicity of novel nanoparticles that enable the co-delivery of DOX and curcumin in the treatment of invasive B cell lymphoma both in vivo and vitro. The polymer nano materials [mPEG-b-P(Glu-co-Phe)] was used to co-load DOX and curcumin (CUR): L-DOX + CUR. DOX signal was measured to determine the ability of the drugs entering the cells by flow cytometry, and the different enrichment areas in the cells were directly observed by confocal microscope. The toxicity of LDOX + CUR was tested by CCK-8 assay in different cells, and the synergistic coefficients were calculated. The cell apoptosis and the possible mechanisms of apoptosis pathways regulation by L-DOX + CUR were examined using flow cytometry and Western Blot. The MTD (maximum tolerable dose) test was performed in mice. Tumor-bearing SCID mice (i.e., BJAB cell) were used to evaluate the in vivo efficacy of L-DOX + CUR. L-DOX + CUR, was prepared successfully, and the mole ratio of DOX and CUR fixed in 1.0:1.2. (DOX loading rate 9.7%, CUR loading rate 8.1%). L-DOX + CUR exhibited increased intracellular delivery and the main enrichment area of DOX was nucleus. L-DOX + CUR increased cytotoxicity, induced higher rates of apoptosis, and had synergistic effect, especially in BJAB cells (min CI 0.019). It even had epigenetic effect and affected miRNA levels favorably by down-regulating miR-21, miR-199a and up-regulating miR-98 and miR-200c. Additionally, L-DOX + CUR increased MTD in Kunming mice (i.e., 25 mg/kg), compared to DOX (10 mg/kg) and L-DOX (20 mg/kg). In BJAB cell bearing SCID mice, L-DOX + CUR treatment suppressed tumor growth compared to DOX or L-DOX alone, and exhibited less weight loss in mice. We developed new polymer nanoparticles-mPEG-b-P (Glu-co-Phe) co-loaded with DOX and DUR. L-DOX + CUR exhibited synergistic cytotoxic and apoptotic effects on invasive B cell lymphoma. Treatment of L-DOX + CUR potentiated tumor killing in xenografts and reduced toxicity in vivo.

Assessment of cardiac function, blood flow and myocardial tissue relaxation parameters at 0.35 T.

A low field strength (B0) system could increase cardiac MRI availability for patients otherwise contraindicated at higher field. Lower equipment costs could also broaden cardiac MR accessibility. The current study investigated the feasibility of cardiac function with steady-state free precession and flow assessment with phase contrast (PC) cine images at 0.35 T, and evaluated differences in myocardial relaxation times using quantitative T1, T2 and T2* maps by comparison with 1.5 and 3 T results in a small cohort of six healthy volunteers. Signal-to-noise ratio (SNR) differences across systems were characterized with proton density-weighted spin echo phantom data. SNR at 0.35 T was lower by factors of 5.5 and 15.0 compared with the 1.5 and 3 T systems used in this study. All cine images at 0.35 T scored 3 or greater on a five-point image quality scale. Normalized blood-myocardium contrast in cine images, left ventricular volumes (end diastolic volume, end systolic volume) and function (ejection fraction and stroke volume) measures at 0.35 T matched 1.5 and 3 T results. Phase-to-noise ratio in 0.35 T PC images (11.7 ± 1.9) was lower than 1.5 T (18.7 ± 5.2) and 3 T (44.9 ± 16.5). Peak velocity and stroke volume determined from PC images were similar across systems. Myocardial T1 increased (564 ± 13 ms at 0.35 T, 955 ± 19 ms at 1.5 T and 1200 ± 35 ms at 3 T) while T2 (59 ± 4 ms at 0.35 T, 49 ± 3 ms at 1.5 T and 40 ± 2 ms at 3 T) and T2* (42 ± 8 ms at 0.35 T, 33 ± 6 ms at 1.5 T and 24 ± 3 ms at 3 T) decreased with increasing B0. Despite SNR deficits, cardiovascular function, flow assessment and myocardial relaxation parameter mapping is feasible at 0.35 T using standard cardiovascular imaging sequences.

A multi-vendor, multi-center study on reproducibility and comparability of fast strain-encoded cardiovascular magnetic resonance imaging.

Myocardial strain is a convenient parameter to quantify left ventricular (LV) function. Fast strain-encoding (fSENC) enables the acquisition of cardiovascular magnetic resonance images for strain-measurement within a few heartbeats during free-breathing. It is necessary to analyze inter-vendor agreement of techniques to determine strain, such as fSENC, in order to compare existing studies and plan multi-center studies. Therefore, the aim of this study was to investigate inter-vendor agreement and test-retest reproducibility of fSENC for three major MRI-vendors. fSENC-images were acquired three times in the same group of 15 healthy volunteers using 3 Tesla scanners from three different vendors: at the German Heart Institute Berlin, the Charité University Medicine Berlin-Campus Buch and the Theresien-Hospital Mannheim. Volunteers were scanned using the same imaging protocol composed of two fSENC-acquisitions, a 15-min break and another two fSENC-acquisitions. LV global longitudinal and circumferential strain (GLS, GCS) were analyzed by a trained observer (Myostrain 5.0, Myocardial Solutions) and for nine volunteers repeatedly by another observer. Inter-vendor agreement was determined using Bland-Altman analysis. Test-retest reproducibility and intra- and inter-observer reproducibility were analyzed using intraclass correlation coefficient (ICC) and coefficients of variation (CoV). Inter-vendor agreement between all three sites was good for GLS and GCS, with biases of 0.01-1.88%. Test-retest reproducibility of scans before and after the break was high, shown by ICC- and CoV values of 0.63-0.97 and 3-9% for GLS and 0.69-0.82 and 4-7% for GCS, respectively. Intra- and inter-observer reproducibility were excellent for both parameters (ICC of 0.77-0.99, CoV of 2-5%). This trial demonstrates good inter-vendor agreement and test-retest reproducibility of GLS and GCS measurements, acquired at three different scanners from three different vendors using fSENC. The results indicate that it is necessary to account for a possible bias (< 2%) when comparing strain measurements of different scanners. Technical differences between scanners, which impact inter-vendor agreement, should be further analyzed and minimized.DRKS Registration Number: 00013253.Universal Trial Number (UTN): U1111-1207-5874.

CArtesian sampling with Variable density and Adjustable temporal resolution (CAVA).

PURPOSE: To develop a variable density Cartesian sampling method that allows retrospective adjustment of temporal resolution for dynamic MRI applications and to validate it in real-time phase contrast MRI (PC-MRI). THEORY AND METHODS: The proposed method, called CArtesian sampling with Variable density and Adjustable temporal resolution (CAVA), begins by producing a sequence of phase encoding indices based on the golden ratio increment. Then, variable density is introduced by nonlinear stretching of the indices. Finally, the elements of the resulting sequence are rounded up to the nearest integer. The performance of CAVA is evaluated using PC-MRI data from a pulsatile flow phantom and real-time, free-breathing data from ten healthy volunteers. RESULTS: CAVA enabled image recovery at various temporal resolutions that were selected retrospectively. For the pulsatile flow phantom, image quality and flow quantification accuracy from CAVA were comparable to that from another pseudo-random sampling pattern with fixed temporal resolution. In addition, flow quantification results based on CAVA were in good agreement with a breath-held segmented acquisition. CONCLUSIONS: By allowing retrospective binning of the MRI data, CAVA provides an avenue to retrospectively adjust the temporal resolution of PC-MRI.

Curcumin improves asthenozoospermia by inhibiting reactive oxygen species reproduction through nuclear factor erythroid 2-related factor 2 activation.

We conducted this study for the purpose of evaluating the protective mechanisms of curcumin against oxidative stress in asthenozoospermic individuals. Asthenozoospermic individuals were grouped into AS group, curcumin treatment group and brusatol + curcumin treatment group. The sperm motility was measured by computer-aided sperm analysis. We conducted flow cytometry and spectrophotometry to assess the levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Chlortetracycline (CTC) was used to examine the acrosomal reaction of spermatozoa. Also, Western blotting was carried to measure antioxidant gene Nrf2 (nuclear factor erythroid 2-related factor) expression level. As our results shown, treatment with curcumin significantly decreased ROS formation and MDA production, compared with spermatozoa of AS group; however, Nrf2 inhibitor, Brusatol, inhibited Nrf2 expression and sperm function. Our results have shown that curcumin might protect spermatozoa by regulating Nrf2 level.