MRI study on the influence of lumbosacral vertebral body and disc factors on lumbar lordosis in children.

PURPOSE: To evaluate the influence of vertebral and disc wedging on the contribution of lumbar lordosis and the change of disc thickness before and after walking based on MRI. METHODS: Cross-sectional study. A total of 96 normally developing children, aged 5.7 ± 3.0 years old, 55 boys and 41 girls. They were divided into 3 groups: Pre-walking group, Walking group, and Post-walking group. PARAMETERS: lumbar lordosis Angle (LLA), the sum of the lumbar disc wedge Angle (∑D), the sum of the lumbar vertebral body wedge Angle (∑B), disc height (DH). RESULTS: (1) LLA, ∑D, ∑B, and DHL1-S1 were 33.2 ± 8.7°, 14.1 ± 8.6°, 11.9 ± 8.6°, and 6.9 ± 1.2 mm, 7.6 ± 1.4 mm, 8.2 ± 1.6 mm, 8.9 ± 1.7 mm, 8.5 ± 1.8 mm. (2) The difference in LLA values between the Pre-walking and the Post-walking group was statistically significant. DH were significantly different among the three groups. (3) In the Post-walking group, LLA value of girls was significantly higher than that of boys, and DHL3 - 4 and DHL4 - 5 values of girls were significantly lower than that of boys. (4) Age had a low positive correlation with LLA and ∑D and a moderate to strong positive correlation with DH; LLA showed a moderate positive correlation with ∑D, and a low positive correlation with ∑B and DH. CONCLUSION: Age and walking activity are the influencing factors of lumbar lordosis and disc thickening. Walking activity can significantly increase lumbar lordosis, and age is the main factor promoting lumbar disc thickening. DHL4-5 was the thickest lumbar intervertebral disc with the fastest intergroup thickening. Disc wedging contributes more to lumbar lordosis than vertebral wedging.

Predictors of lung cancer subtypes and lymph node status in non-small-cell lung cancer: intravoxel incoherent motion parameters and extracellular volume fraction.

OBJECTIVE: To determine the performance of intravoxel incoherent motion (IVIM) parameters and the extracellular volume fraction (ECV) in distinguishing between different subtypes of lung cancer and predicting lymph node metastasis (LNM) status in patients with non-small-cell lung cancer (NSCLC). METHODS: One hundred sixteen patients with lung cancer were prospectively recruited. IVIM, native, and postcontrast T1 mapping examinations were performed, and the T1 values were measured to calculate the ECV. The differences in IVIM parameters and ECV were compared between NSCLC and small-cell lung cancer (SCLC), adenocarcinoma (Adeno-Ca) and squamous cell carcinoma (SCC), and NSCLC without and with LNM. The assessment of each parameter's diagnostic performance was based on the area under the receiver operating characteristic curve (AUC). RESULTS: The apparent diffusion coefficient (ADC), true diffusion coefficient (D), and ECV values in SCLC were considerably lower compared with NSCLC (all p < 0.001, AUC > 0.887). The D value in SCC was substantially lower compared with Adeno-Ca (p < 0.001, AUC = 0.735). The perfusion fraction (f) and ECV values in LNM patients were markedly higher compared with those without LNM patients (p < 0.01, < 0.001, AUC > 0.708). CONCLUSION: IVIM parameters and ECV can serve as non-invasive biomarkers for assisting in the pathological classification and LNM status assessment of lung cancer patients. CRITICAL RELEVANCE STATEMENT: IVIM parameters and ECV demonstrated remarkable potential in distinguishing pulmonary carcinoma subtypes and predicting LNM status in NSCLC. KEY POINTS: Lung cancer is prevalent and differentiating subtype and invasiveness determine the treatment course. True diffusion coefficient and ECV showed promise for subtyping and determining lymph node status. These parameters could serve as non-invasive biomarkers to help determine personalized treatment strategies.

Role of Dynamic Contrast-Enhanced Magnetic Resonance Imaging Parameters and Extracellular Volume Fraction as Predictors of Lung Cancer Subtypes and Lymph Node Status in Non-Small-Cell Lung Cancer Patients.

Objective: The aim of this study is to determine whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)-based quantitative parameters and the extracellular volume fraction (ECV) can differentiate small-cell lung cancer (SCLC) from non-small-cell lung cancer (NSCLC), squamous-cell carcinoma (SCC) from adenocarcinoma (Adeno-Ca), and NSCLC with lymph node metastasis from NSCLC without lymph node metastasis. Materials and methods: We prospectively enrolled patients with lung cancer (41 Adeno-Ca, 29 SCC, and 23 SCLC) who underwent DCE-MRI and enhanced T1 mapping prior to histopathological confirmation. Quantitative parameters based on DCE-MRI and ECV based on T1 mapping were compared between SCLC and NSCLC patients, between SCC and Adeno-Ca patients, and between NSCLC patients with and without lymph node metastasis. The area under the receiver-operating characteristic curve (AUC) was used to evaluate the diagnostic performance of each parameter. Spearman rank correlation was used to clarify the associations between ECV and DCE-MRI-derived parameters. Results: Ktrans, Kep, Ve, and ECV all performed well in differentiating SCLC from NSCLC (AUC > 0.729). Ktrans showed the best performance in differentiating SCC from Adeno-Ca (AUC = 0.836). ECV could differentiate NSCLCs with and without lymph node metastases (AUC = 0.764). ECV showed a significant positive correlation with both Ktrans and Ve. Conclusions: Ktrans is the most promising imaging parameter to differentiate SCLC from NSCLC, and Adeno-Ca from SCC. ECV was helpful in detecting lymph node metastasis in NSCLC. These imaging parameters may help guide the selection of lung cancer treatment.

Brain structural changes in preschool children with MRI-negative epilepsy.

PURPOSE: To investigate abnormalities in cortical and subcortical structures of the brain in preschool children with MRI-negative epilepsy. METHODS: Cortical thickness, cortical mean curvature, cortical surface area, cortical volume, and volumes of subcortical structures were measured using Freesurfer software in preschool children with epilepsy and age-matched controls. RESULTS: Findings showed cortical thickening in the left fusiform gyrus, left middle temporal gyrus, right suborbital sulcus, and right gyrus rectus, and cortical thinning mainly in the parietal lobe of preschool children with epilepsy compared to controls. The difference in cortical thickness in the left superior parietal lobule remained after correction for multiple comparisons and was negatively correlated with duration of epilepsy. Cortical mean curvature, surface area, and volume were mainly altered in the frontal and temporal lobes. Changes in mean curvature in the right pericallosal sulcus were positively correlated with age at seizure onset, and changes in mean curvature in the left intraparietal sulcus and transverse parietal sulcus were positively correlated with frequency of seizures. There were no significant differences in the volumes of the subcortical structures. CONCLUSION: Changes in preschool children with epilepsy occur in the cortical rather than subcortical structures of the brain. These findings further our understanding of the effects of epilepsy in preschool children and will inform management of epilepsy in this patient population.

Modification of Chloroplast Antioxidant Capacity by Plastid Transformation.

As immobile organisms, green plants must be frequently challenged by a broad range of environmental stresses. During these constantly adverse conditions, reactive oxygen species (ROS) levels can rise extremely in plants, leading to cellular dysfunction and cell death presumably due to irreversible protein overoxidation. Once considered merely as deleterious molecules, cells seek to remove them as efficiently as possible. To enhance ROS scavenging capacity, genes encoding antioxidative enzymes can be directly expressed from the genome of plastid (chloroplast), a major compartment for ROS production in photosynthetic organisms. Thus, overexpression of antioxidant enzymes by plastid engineering may provide an alternative to enhance plant's tolerance to stressful conditions specifically related with chloroplast-derived ROS. Here, we describe basic procedures for expressing glutathione reductase, a vital component of ascorbate-glutathione pathway, in tobacco via plastid transformation technology.

Genetic Manipulation of Reactive Oxygen Species (ROS) Homeostasis Utilizing CRISPR/Cas9-Based Gene Editing in Rice.

Reactive oxygen species (ROS) are now recognized as key signals in plant stress responses. Adverse environmental conditions can either promote ROS production or downregulate antioxidative enzymes, leading to the alteration of redox homeostasis and activation of ROS-linked stress signaling. To uncover their signaling mechanisms and to characterize related components, genetic modification of ROS homeostasis is a central approach. CRISPR/Cas9-based genome editing system has become a powerful tool for gene mutation in a variety of organisms, including plants. Within this chapter, we describe a method that can be applied to manipulate ROS homeostasis in rice (Oryza sativa L.) utilizing CRISPR/Cas9 technology. Step-by-step protocols including the design and construction of Cas9/sgRNA, agrobacterium-mediated transformation, and mutation characterization are described. Application of this system in editing a rice catalase gene CatC, a key antioxidative enzyme in controlling ROS homeostasis, is also presented.

Morphological development of the human fetal striatum during the second trimester.

The morphological development of the fetal striatum during the second trimester has remained poorly described. We manually segmented the striatum using 7.0-T MR images of the fetal specimens ranging from 14 to 22 gestational weeks. The global development of the striatum was evaluated by volume measurement. The absolute volume (Vabs) of the caudate nucleus (CN) increased linearly with gestational age, while the relative volume (Vrel) showed a quadratic growth. Both Vabs and Vrel of putamen increased linearly. Through shape analysis, the changes of local structure in developing striatum were specifically demonstrated. Except for the CN tail, the lateral and medial parts of the CN grew faster than the middle regions, with a clear rostral-caudal growth gradient as well as a distinct "outside-in" growth gradient. For putamen, the dorsal and ventral regions grew obviously faster than the other regions, with a dorsal-ventral bidirectional developmental pattern. The right CN was larger than the left, whereas there was no significant hemispheric asymmetry in the putamen. By establishing the developmental trajectories, spatial heterochrony, and hemispheric dimorphism of human fetal striatum, these data bring new insight into the fetal striatum development and provide detailed anatomical references for future striatal studies.

Putrescine regulates stomatal opening of cucumber leaves under salt stress via the H2O2-mediated signaling pathway.

The stomatal aperture is imperative for photosynthesis in higher plants. The function of polyamines (PAs) in stomatal regulation under a stressful environment has not been fully determined. In this study, we demonstrated the mechanism by which putrescine (Put) regulates stomatal changes in cucumber leaves under salt stress. The results showed that foliar application of Put alleviated the decrease of stomatal aperture and photosynthesis caused by salt stress and promoted plant growth. Exogenous Put caused a significant increase in endogenous PAs and hydrogen peroxide (H2O2) levels by 105.43% and 27.97%, respectively, while decreased abscisic acid (ABA) content by 67.68% under salt stress. However, application of inhibitors of aminoguanidine hydrochloride (AG), 1, 8-diaminooctane (1, 8-DO), diphenyleneiodonium chloride (DPI) and salicylhydroxamic acid (SHAM) upregulated the 9-cis-cyclocarotenoid dioxygenase (NCED) gene and downregulated the reduced glutathione synthetase (GSHS) gene. These inhibitors also decreased the stomatal aperture, levels of H2O2 and reduced glutathione (GSH), but increased the ABA content under salt stress and Put treatment conditions. The order of influence is AG > 1, 8-DO > DPI > SHAM. However, Put-induced downregulation of ABA content and upregulation of GSH content under salt stress were effectively blocked by N, N'-dimethylthiourea (DMTU, H2O2 scavenger) and 1-chloro-2,4-dinitrobenzene (CDNB, GSH scavenger) treatments. Taken together, these results suggest that Put induced the formation of H2O2 signaling mediates the degradation of PAs by diamine oxidase (DAO), increasing GSH content and inhibiting the accumulation of ABA in leaves, thereby promoting stomatal opening in salt-stressed cucumber leaves.

Inhibitory effect of pirfenidone on pulmonary fibrosis in patients with acute paraquat poisoning.

OBJECTIVE: To study the efficacy of pirfenidone (PFD) on patients with pulmonary fibrosis caused by acute paraquat (PQ) poisoning. METHODS: A total of 86 patients with pulmonary fibrosis caused by acute PQ poisoning admitted to our hospital were analyzed retrospectively. All of them successfully received the standard 21-day treatment based on "Taishan Consensus", and they were assigned to the PFD group or the NO-PFD group according to whether they received PFD treatment (at 200 mg/time, 3 times/day) for 6 months after discharge. The two groups were compared in effective treatment rate, mortality and incidence of adverse reactions such as liver and kidney function damage, pulmonary fibrosis-associated indexes, pulmonary function-associated indexes, and arterial blood gas indexes before and after therapy. RESULTS: The PFD group showed a notably higher effective treatment rate than the NO-PFD group (P<0.05). Additionally, the PFD group showed notably lower levels of serum hyaluronic acid (HA), laminin (LN), type IV collagen (CIV), and type III procollagen (PCIII), and notably higher levels of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC than the NO-PFD group (all P<0.001), and the PFD group also showed significantly higher levels of arterial blood gas indexes including arterial partial pressure of oxygen (PaO2) and PaO2/inspired oxygen (FIO2) than the NO-PFD group (both P<0.001). Moreover, the Kaplan-Meier survival curves showed that the survival rate of the patients in PFD group was significantly higher than that in the NO-PFD group (P<0.05). CONCLUSION: With a high safety, PFD can effectively improve the treatment efficacy in patients with pulmonary fibrosis caused by acute PQ poisoning. PFD can improve the pulmonary function and arterial blood gas status of patients, without causing obvious liver and kidney damage.

Normal fetal development of the cervical, thoracic, and lumbar spine: A postmortem study based on magnetic resonance imaging.

OBJECTIVE: Before evaluating spinal pathology, it is essential to have knowledge of the normal spinal development at different gestational ages. This study aims to characterize normal spinal growth in human fetuses during the second and third trimesters. METHODS: Postmortem 3.0 T magnetic resonance imaging (MRI) was performed on 55 fetuses at 17-42 gestational weeks by using three-dimensional T2-weighted sequences. Morphological changes and quantitative measurements of the fetal spine were assessed. The correlation between centrum ossification center volume (COCV) and gestational age was investigated. RESULTS: The cervical, thoracic, and lumbar COCVs showed a positive relationship with gestational age (p < 0.05). No gender differences were found in the volumetric development of the cervical, thoracic, and lumbar centrum ossification centers (COCs). The average volumetric growth rate per COC was larger in the lumbar spine than in the cervical and thoracic spine. The L1-L5 COCVs also showed a linear positive relationship with gestational age. CONSULTS: Postmortem 3.0 T MRI clearly demonstrated spinal changes in external contour and internal structure with gestational age. These findings expand our understanding of the early growth pattern of the human spine and could be further used to assess the developmental conditions of the fetal spine.

Hydrogen sulfide: a multi-tasking signal molecule in the regulation of oxidative stress responses.

Accumulating evidence suggests that hydrogen sulfide (H2S) is an important signaling molecule in plant environmental interactions. The consensus view amongst plant scientists is that environmental stress leads to enhanced production and accumulation of reactive oxygen species (ROS). H2S interacts with the ROS-mediated oxidative stress response network at multiple levels, including the regulation of ROS-processing systems by transcriptional or post-translational modifications. H2S-ROS crosstalk also involves other interacting factors, including nitric oxide, and can affect key cellular processes like autophagy. While H2S often functions to prevent ROS accumulation, it can also act synergistically with ROS signals in processes such as stomatal closure. In this review, we summarize the mechanisms of H2S action and the multifaceted roles of this molecule in plant stress responses. Emphasis is placed on the interactions between H2S, ROS, and the redox signaling network that is crucial for plant defense against environmental threats.

Synthesis of gemini ammonium sulfobetaine and its proppant suspension and gel-breaking mechanisms.

In this study, gemini ammonium sulfobetaine (GAS) is designed and synthesized using isophorone diisocyanate connecting the ammonium sulfobetaines (AS) to obtain a viscoelastic surfactant exhibiting better viscosification and salt resistance. AS is prepared using the monomers of erucic acid, N-dimethyl-1,3-propanediamine, and 3-chloro-2-hydroxypropanesulfonic acid sodium. The properties of GAS and its proppant suspension as well as the gel-breaking mechanisms are investigated. The critical micelle concentration of GAS is 2.1 × 10-7 mol mL-1. GAS exhibits good salt resistance, and the viscosity is considerably high under acidic conditions. At 0.5 Hz, the storage modulus G' of GAS is 60, 120, and 640 mPa when the concentration is 0.3, 0.5, and 1.0 wt%, respectively. Its proppant suspension is optimal under acidic conditions. When the pH is high, the setting velocities are clearly observed to increase. When the pH is 12, the rate of decline is more than 50% after 200 min. Some of the worm-like micelles adsorbed on the proppant surface participate in the formation of the three-dimensional network, appropriately supporting the proppant-carrying performance. When potassium permanganate is used as the gel breaker, the characterization of the GAS gel-breaking liquid indicates that the double bond is disintegrrated by the gel breaker. Upon gel breaking, the average hydrodynamic radius of the GAS gel-breaking solution decreases to 176.2 nm from 492.3 nm.

Accurate diagnosis of fetal cleft lip/palate by typical signs of magnetic resonance imaging.

OBJECTIVE: This study aims to evaluate the accuracy of magnetic resonance imaging (MRI) in diagnosing orofacial clefts and proposes specific signs for determining the type of cleft. METHODS: Pregnant women in whom fetal facial malformations are suspected by ultrasonography (US) underwent 1.5 T MRI. The accuracy of the prenatal US and MRI diagnosis was compared with the postnatal findings. RESULTS: A total of 71 fetuses were included in the final analysis, which comprised of 35 cases of isolated cleft lip, six cases of cleft lip and alveolus, 21 cases of cleft lip and palate, four cases of isolated cleft palate, and five normal fetuses. MRI was more sensitive than US (MRI 100%, US 77.5%; Fisher's exact test: MRI vs US P=0.000). The accuracy of MRI for all types was 100%. Specific signs (Inverted T, L/anti-L, U, and "Notch" signs) were proposed, indicating the normal hard, unilateral cleft, bilateral cleft, and cleft soft palates, respectively, which can facilitate the identification of different types of cleft palates. CONCLUSION: MRI can accurately diagnose the type of cleft based on typical signs, which can serve as a definite diagnostic modality and an effective supplement of US.

Normal development of costal element ossification centers of sacral vertebrae in the fetal spine: a postmortem magnetic resonance imaging study.

PURPOSE: This postmortem magnetic resonance imaging (MRI) study of the fetal spine aimed to describe the timing of appearance, shape, volume, and relative positions of the S1-S3 costal element ossification centers (CEOCs). METHODS: We obtained sagittal 3D dual-echo steady-state with water excitation T2 images of the entire spine in 71 fetuses (gestational ages (GAs), 17-42 weeks). Computed tomography and histological examinations were performed on two fetal specimens (GAs, 21 and 30 weeks) to validate the MR images. The presence/absence of each sacral CEOC was recorded according to the GA. CEOC volume was measured. We analyzed the CEOC position relative to the vertebral column and ilium. RESULTS: The S1, S2, and S3 CEOCs first appeared at 23, 22, and 29 weeks, respectively. The S1 and S2 CEOCs could be detected in all fetuses with GAs of ≥ 30 weeks and ≥ 35 weeks, respectively, while the S3 CEOCs were variably present until term. The percentages of detection of the S1 and S2 CEOCs were significantly greater than that of the S3 CEOCs at each GA. At S1 and S2, the CEOC volume increased exponentially with GA. The relative positions of the S1 and S2 CEOCs, but not the S3 CEOCs, significantly correlated with GA (P < 0.001). CONCLUSION: We have described the timeline of appearance as well as the volume and position of the S1-S3 CEOCs in the fetal spine on postmortem MRI according to GA.

Peroxisome proliferator-activated receptor-gamma activation attenuates diabetic cardiomyopathy via regulation of the TGF-ß/ERK pathway and epithelial-to-mesenchymal transition.

Diabetic cardiomyopathy (DCM) is a kind of disease caused by metabolic disorders and microangiopathy. The main pathophysiological changes of DCM include fibrosis, myocardial cell apoptosis and autonomic neuropathy. Therefore, treatment aimed at these processes may benefit patients with DCM. We designed an experiment with the peroxisome proliferator-activated receptor-gamma (PPARγ) agonist GW 1929 to detect whether the activation of PPARγ could alleviate the degree of DCM. To further detect the mechanism of PPARγ in DCM, we used the PPARγ antagonist GW 9662 and ERK antagonist PD 098059 both in vitro and in vivo and found that PPARγ functioned by inhibiting ERK. We also performed Western blot, PCR, ELISA, immunohistochemistry, TUNEL assay, Sirius red staining and gelatin zymography to investigate inflammation, apoptosis, MMP activity and epithelial-to-mesenchymal transition (EMT). The results showed that the activation of PPARγ inhibited these reactions and inhibiting ERK also simulated this phenomenon. In conclusion, these results demonstrated that PPARγ activation in the diabetic myocardium of mice reduces myocardial fibrosis via regulation of the TGF-ß/ERK pathway and EMT.

Normal development of sacrococcygeal centrum ossification centers in the fetal spine: a postmortem magnetic resonance imaging study.

PURPOSE: To describe the temporal pattern of the appearance of the S1-Co1 centrum ossification centers (COCs) and provide reference data for the S1-S5 COCs and sacral length at various gestational ages (GAs). METHODS: Postmortem magnetic resonance imaging (MRI) was performed on 71 fetuses (GA, 17-42 weeks) using the 3D dual-echo steady-state with water excitation T2 sequence in the sagittal plane. To confirm the reliability of this sequence, the MRI data were compared with the CT and histologic data obtained from two fetuses (GAs, 21 and 30 weeks). The presence or absence of each sacrococcygeal COC was recorded. Sacral length and S1-S5 COC height, sagittal diameter, transverse diameter, cross-sectional area, and volume were measured. RESULTS: All fetuses showed S1-S3 COCs by 17 weeks, S4 COCs by 19 weeks, and S5 COCs by 28 weeks. The S4, S5, and Co-1 COCs were visualized in 70 (98.59%), 51 (71.83%), and 21 (29.58%) fetuses, respectively. Sacral length, height, sagittal, and transverse diameters increased linearly, while cross-sectional area and volume increased exponentially with advancing GA. Mean growth rates of the sagittal and transverse diameters, cross-sectional area, and volume, but not of height, significantly differed among the S1-S5 vertebrae. CONCLUSION: We have presented the timing of appearance of individual sacrococcygeal COCs and the age-specific, normative MRI reference values for sacral length and the morphometric parameters of the sacral COCs, which are of clinical importance in the diagnosis of congenital sacral abnormalities and skeletal dysplasia.