Augmenter of liver regeneration promotes mitochondrial biogenesis in renal ischemia-reperfusion injury.

Mitochondria are the center of energy metabolism in the cell and the preferential target of various toxicants and ischemic injury. Renal ischemia-reperfusion (I/R) injury triggers proximal tubule injury and the mitochondria are believed to be the primary subcellular target of I/R injury. The promotion of mitochondrial biogenesis (MB) is critical for the prevention I/R injury. The results of our previous study showed that augmenter of liver regeneration (ALR) has anti-apoptotic and anti-oxidant functions. However, the modulatory mechanism of ALR remains unclear and warrants further investigation. To gain further insight into the role of ALR in MB, human kidney (HK)-2 cells were treated with lentiviruses carrying ALR short interfering RNA (siRNA) and a model of hypoxia reoxygenation (H/R) injury in vitro was created. We observed that knockdown of ALR promoted apoptosis of renal tubular cells and aggravated mitochondrial injury, as evidenced by the decrease in the mitochondrial respiratory proteins adenosine triphosphate (ATP) synthase subunit ß, cytochrome c oxidase subunit 1, and nicotinamide adenine dinucleotide dehydrogenase (ubiquinone) beta subcomplex 8. Meanwhile, the production of reactive oxygen species was increased and ATP levels were decreased significantly in HK-2 cells, as compared with the siRNA/control group (p < 0.05). In addition, the mitochondrial DNA copy number and membrane potential were markedly decreased. Furthermore, critical transcriptional regulators of MB (i.e., peroxisome proliferator-activated receptor-gamma coactivator 1 alpha, mitochondrial transcription factor A, sirtuin-1, and nuclear respiratory factor-1) were depleted in the siRNA/ALR group. Taken together, these findings unveil essential roles of ALR in the inhibition of renal tubular cell apoptosis and attenuation of mitochondrial dysfunction by promoting MB in AKI.

Risk factors for severe COVID-19 infection and the impact of COVID-19 infection on disease progression among patients with AAV.

To identify risk factors for COVID-19 infection and investigate the impact of COVID-19 infection on chronic kidney disease (CKD) progression and vasculitis flare in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). This cohort study retrospectively analyzed the prevalence and severity of COVID-19 infection in 276 patients with AAV who were followed up. Logistic regression was employed to estimate the risk of COVID-19 infection as well as CKD progression and vasculitis flare upon COVID-19 infection. During the 6-month observation period, 213 (77.2%) of 276 patients were diagnosed with COVID-19 infection. Of these 213 patients, 49 (23.0%) had a COVID-19-related inpatient admission, including 17 patients who died of COVID-19 infection. AAV patients with severe COVID-19 infection were more likely to be male (OR 1.921 [95% CI 1.020-3.619], P = 0.043), suffered from worse kidney function (serum creatinine [Scr], OR 1.901 [95% CI 1.345-2.687], P < 0.001), had higher C-reactive protein (CRP) (OR 1.054 [95% CI 1.010-1.101], P = 0.017) and less likely to have evidence of initial vaccination (OR 0.469 [95% CI 0.231-0.951], P = 0.036), and Scr and COVID-19 vaccination were proven to be significantly associated with severe COVID-19 infection even after multivariable adjustment. Severe COVID-19 infection was significantly associated with subsequent CKD progression (OR 7.929 [95% CI 2.030-30.961], P = 0.003) and vasculitis flare (OR 11.842 [95% CI 1.048-133.835], P = 0.046) among patients with AAV. AAV patients who were male, and with worse kidney function were more susceptible to severe COVID-19 infection, which subsequently increased the risk of CKD progression and vasculitis flare.

Effects and molecular mechanism of pachymic acid on ferroptosis in renal ischemia reperfusion injury.

Acute kidney injury (AKI) is a common clinical disease. Ferropotosis, a new type of regulatory cell death, serves an important regulatory role in AKI. Pachymic acid (PA), a lanostane­type triterpenoid from Poria cocos, has been reported to be protective against AKI. However, the protective mechanism of PA in AKI is not yet fully understood. The present study aimed to investigate the effect and molecular mechanism of PA on ferroptosis in renal ischemia reperfusion injury in vivo. A total of 30 mice were intraperitoneally injected with 5, 10 and 20 mg/kg PA for 3 days. A bilateral renal pedicle clip was used for 40 min to induce renal ischemia­reperfusion injury and establish the model. The results demonstrated that treatment with PA decreased serum creatinine and blood urea nitrogen, and ameliorated renal pathological damage. Transmission electron microscopy revealed no characteristic changes in ferroptosis in the mitochondria of the renal tissue in the high­dose PA group, and only mild edema. Furthermore, treatment with PA increased glutathione expression, and decreased the expression levels of malondialdehyde and cyclooxygenase 2. Treatment with PA enhanced the protein and mRNA expression levels of the ferroptosis related proteins, glutathione peroxidase 4 (GPX4), solute carrier family 7 (cationic amino acid transporter, y+ system) member 11 (SLC7A11) and heme oxygenase 1 (HO­1) in the kidney, and increased the expression levels of nuclear factor erythroid derived 2 like 2 (NRF2) signaling pathway members. Taken together, the results of the present study suggest that PA has a protective effect on ischemia­reperfusion induced acute kidney injury in mice, which may be associated with the inhibition of ferroptosis in the kidneys through direct or indirect activation of NRF2, and upregulation of the expression of the downstream ferroptosis related proteins, GPX4, SLC7A11 and HO­1.

Effect of Novel Rhythmic Physical Activities on Fundamental Movement Skills in 3- to 5-Year-Old Children.

Based on traditional rhythmic physical activities (TRPA), we created novel rhythmic physical activities (NRPA). The purpose of this study was to verify the effectiveness of NRPA in improving children's fundamental movement skills (FMS). 289 children (135 boys, 154 girls) from 3 to 5 years old were randomly divided into an experimental group and a control group. Tools of Test of Gross Motor Development-2, Tekscan instrument, and balance beam were to assess children's FMS. Two-way repeated measures ANOVA was used to analyze and compare the changes in the related parameters of locomotor, manipulative, and balance movement skills before and after intervention (groups × time). NRPA performed significantly better than TRPA from pre- to posttest for FMS. Furthermore, NRPA had significantly higher posttest scores than TRPA. Therefore, NRPA could effectively promote the development of children's FMS due to the concept of the sensitive period of motor development, the variability of movement parameters, and the incomplete repeatability of practice methods.

Augmenter of Liver Regeneration Alleviates Renal Hypoxia-Reoxygenation Injury by Regulating Mitochondrial Dynamics in Renal Tubular Epithelial Cells.

Mitochondria are highly dynamic organelles that constantly undergo fission and fusion processes that closely related to their function. Disruption of mitochondrial dynamics has been demonstrated in acute kidney injury (AKI), which could eventually result in cell injury and death. Previously, we reported that augmenter of liver regeneration (ALR) alleviates renal tubular epithelial cell injury. Here, we gained further insights into whether the renoprotective roles of ALR are associated with mitochondrial dynamics. Changes in mitochondrial dynamics were examined in experimental models of renal ischemia-reperfusion (IR). In a model of hypoxia-reoxygenation (HR) injury in vitro , dynamin-related protein 1 (Drp1) and mitochondrial fission process protein 1 (MTFP1), two key proteins of mitochondrial fission, were downregulated in the Lv-ALR + HR group. ALR overexpression additionally had an impact on phosphorylation of Drp1 Ser637 during AKI. The inner membrane fusion protein, Optic Atrophy 1 (OPA1), was significantly increased whereas levels of outer membrane fusion proteins Mitofusin-1 and -2 (Mfn1, Mfn2) were not affected in the Lv-ALR + HR group, compared with the control group. Furthermore, the mTOR/4E-BP1 signaling pathway was highly activated in the Lv-ALR + HR group. ALR overexpression led to suppression of HR-induced apoptosis. Our collective findings indicate that ALR gene transfection alleviates mitochondrial injury, possibly through inhibiting fission and promoting fusion of the mitochondrial inner membrane, both of which contribute to reduction of HK-2 cell apoptosis. Additionally, fission processes are potentially mediated by promoting tubular cell survival through activating the mTOR/4E-BP1 signaling pathway.

Balance, Proprioception, and Gross Motor Development of Chinese Children Aged 3 to 6 Years.

The authors' aim was to find the features of balance, proprioception, and gross motor development of Chinese children 3-6 years old and their correlations, provide theoretical support for promoting children's motor development, and enrich the world theoretical system of motor development. This study used a Tekscan foot pressure measurement instrument (Tekscan, Inc., Boston, MA), walking on a balance beam, Xsens 3-dimensional positional measuring system (Xsens Technologies, Enschede, the Netherlands), and Test of Gross Motor Development-2 to assess static balance, dynamic balance, knee proprioception, and levels of gross motor development (GMD) of 3- to 6-year-old children (n = 60) in Beijing. The results are as follows: children had significant age differences in static balance, dynamic balance, proprioception, and levels of GMD; children had significant gender differences in static balance, proprioception, and levels of GMD; children's static balance, dynamic balance, and proprioception had a very significant positive correlation with GMD (p < .01), but no significant correlation with body mass index.

[Inverse iterative correction for translational motion artifact of magnetic resonance imaging based on histogram entropy minimization].

During the acquisition of a magnetic resonance images (MRI), blurring and ghosting artifacts caused by the patient's motion can seriously affect the result of diagnosis. A novel automatic post-processing strategy, inverse iterative correction (IIC), has been developed to suppress MRI artifacts due to the object's in-plane rigid-body motion. By means of the proposed histogram-based entropy function, IIC method uses two successive steps to reduce the simulated motion artifacts: first, the inverse phase errors are added to all possible simulated patient's motion directions, and in the second step, the actual directions and displacement from the patient's motion are estimated to properly correct the phase, hence remove the artifacts after searching all the trial directions. To verify its feasibility, the proposed method was used to reduce rigid-motion artifacts due to simulated motion in MRI images. The experimental results showed that the new algorithm significantly outperforms over the entropy auto-focus compensation algorithm on the quality of corrections for the motion artifacts and computational cost.

[Three-dimensional reconstruction of human organs based on magnetic resonance imaging data].

OBJECTIVE: To build proper three-dimensional models of human organs for radiation dose calculation. METHOD: Human organ models were built by contour reconstruction algorithm conforming to 4 criteria. The contours of the organs were extracted based on the contours of the reconstructed organ surfaces, and the three-dimensional models with smooth surface, exact structure and good visibility were completed by computer graphic techniques such as lighting, smoothing, and normal average. RESULT AND CONCLUSION: Several organ models were successfully reconstructed, suggesting that this method is suitable for building three-dimensional digital human organ models which can meet the need for dose calculation.

Registration of serial tissue section images.

OBJECTIVE: This study aims to tackle the problem of image registration during computer-assisted three-dimensional (3D) reconstruction of serial tissue sections. METHODS: We proposed segmentation-counting algorithm for computerized image registration on the basis of joint histogram. This approach utilizes thresholding of the 2 images to be registered, and the criterion function is defined as the counting in a specific region of the joint histogram. The registration parameters can be obtained by optimizing the criterion function. RESULTS: In the trial application of this approach in image registration for the serial tissue sections of mouse wse embryos, a more efficient result was achieved. CONCLUSION: The method can rapidly accomplish the image registration task for serial tissue sections with simpler calculation processes.

Elastic registration of medical images through multiquadric method.

OBJECTIVE: To improve the precision and reliability of elastic registration of the medical images and to simplify the registration process. METHODS: Previous study concerning elastic registration mostly focused on manual selection of the landmarks and then use of adequate interpolating for elastic transformation. The landmarks extraction, however, was prone to error that often showed impact on the registration results, besides the difficulty and time consumption of manual identification of the landmarks. On the basis of Multiquadric method that allowed smooth adjustment of the parameters, we utilized a semi-automatic method to extract the landmarks by combining these 2 steps, and proposed a novel registration method. RESULTS: Using this method for medical image elastic registration, rapid and accurate registration between standard and deformed images was achieved. CONCLUSION: The method proposed presently is accurate, convenient and reliable.

[Risks related to disability on children aged 0-4 in China: analysis on the supporting effects from family].

OBJECTIVE: This study aimed to explore the correlated effects of family environment on children aged 0-4 who were suffered from disabilities. Economic conditions of the families and socio-economic status of the parents were also analyzed. METHODS: Based on the database from the National Sample Survey on Disability in 2006, a new database was intercepted with the information of children aged 0-4 and their parents. The total sample size was 73 394. Descriptive analysis and binary logistic regression were used to explore the effects related to family environment. Software used in statistical analysis was SPSS 16.0. RESULTS: The risks of disability started before the age of 3, and increased along with age (the odds ratios on children at 0 to 4 years old were 0.47, 0.66, 0.90, 1.56 and 1.47), which described the "cumulative" nature of prevalence levels of disability. The risk of disability among male children was higher than female (OR = 0.82). The lower the per capita household income was, the higher the risks of disability of the children (OR(≤683) = 1.80; OR(684-944) = 1.79; OR(945-2948) = 1.23; OR(2949-7254) = 0.71; OR(≥7255) = 0.34) appeared. When living together with parents under the same roof, the risk of disability was significantly correlated with their parents' schooling: literate vs. illiteracy (with father P ≤ 0.001, OR = 2.18 and mother P = 0.02, OR = 1.82). Regarding the parents elementary school education, it appeared that only on father, the result was P = 0.05, OR = 1.56. Employment status of the father was not significantly correlated with children's incidence of disability, while the mother's employment status was significant (P = 0.02, OR = 1.19). Data from the descriptive analysis showed that factors as first marriage and remarriage of the mother were significantly correlated to their children's occurrence of disability while remarriage of the father was also a significant factor. However, in multivariate analysis, both father and mother's marriage status were not significantly important. CONCLUSION: Reducing the risk of disability was important on the health of children. Among younger children, the family environment appeared to have the direct impact on the occurrence of disability.

[Virtual colonoscopy navigation based on colon division].

OBJECTIVE: To develop a virtual navigation mode to enlarge the field of view and decrease the deformation of the visual area. METHOD: The method was implemented in 3 steps. The entire colon was first divided into consecutive sections, and each section was split into two halves by a plane. The virtual camera was finally assigned onto each half of the sections for navigation. RESULTS: Adequate subsections were achieved with this method, which also offer an enlarged field of view for the benefit of focal inspection. CONCLUSION: The division navigation mode is suitable for the development of a virtual colonoscopy navigation and diagnosis system.

[Gibbs artifact reduction in magnetic resonance images based on inverse diffusion].

In magnetic resonance imaging (MRI), Gibbs artifact is often introduced by the reconstruction involving only part of the k-space data. The current methods of Gibbs artifact reduction are generally based on the k-space data. In this paper, an image processing method based on inverse diffusion is proposed. This method is directly applied to the MR images, which can achieve the reduction of artifacts while enhancing the edge by the diffusion of pixel gray value. Experiments showed that the Gibbs artifact was effectively reduced and the valuable details of the images were maintained.