Evaluation of renal tubular function by multiparametric functional MRI in early diabetes.

Purpose To evaluate the tubular function in an alloxan-induced type 1 diabetes mellitus (DM) rabbit model measured by renal oxygenation (R2*), oxygen extraction fraction (OEF), and renal blood flow (RBF) using blood oxygenation level dependent, asymmetric spin echo, and arterial spin labeling MRI. Methods Twenty-six rabbits were randomized into the 3-day DM group (n = 13) and the 7-day DM group (n = 13). We performed pairs of multiparametric MRIs (before and after furosemide injection) at baseline and 3/7 days post-DM, and scored pathological kidney injury. We performed statistical analyses using non-parametric, chi-square, and Spearman correlation tests. Results At baseline, medullary R2* significantly decreased by 24.97% and 16.74% in the outer and inner stripes of the outer medulla (OS and IS, p = 0.006 and 0.003, respectively) after furosemide administration. While the corresponding OEF decreased by 15.91% for OS and 16.67% for IS (both p = 0.003), and no significant change in medullary RBF was observed (p > 0.05). In the 3-day DM group, the decrease of medullary R2* and OEF post-furosemide became unremarkable, suggesting tubular dysfunction. We noticed similar changes in the 7-day DM group. Correlation analysis showed pathological tubular injury score significantly correlated with medullary ∆R2* (post-furosemide - pre-furosemide difference, r = 0.82 for OS and 0.82 for IS) and ∆OEF (r = 0.82 for OS and 0.82 for IS) (p < 0.001, respectively). Conclusion: The combination of medullary OEF and R2* in response to furosemide could detect renal tubular dysfunction in early DM.

Phytoremediation of contaminated sediment combined with biochar: Feasibility, challenges and perspectives.

The accumulation of contaminants in sediments is accelerated by human activities and poses a major threat to ecosystems and human health. In recent years, various remediation techniques have been developed for contaminated sediments. In this review, a bibliometric analysis of papers on sediment remediation indexed in the WOS database between 2009 and 2023 was conducted using VOSviewer. We describe the development of biochar and plants for sediment contaminant removal. However, the single processes of biochar remediation and phytoremediation can be impeded by (i) low efficiency, (ii) poor tolerance of plants towards pollutants, (iii) difficulty in biochar to degrade pollutants, and (iv) biochar aging causing secondary pollution. Fortunately, combination remediation, realized through the combination of biochar and plants, can overcome the shortcomings of their individual applications. Therefore, we suggest that the remediation of contaminants in sediments can be accomplished by combining biochar with macrophytes and considering multiple limiting factors. Here, we explore the challenges that co-remediation with biochar and macrophytes will face in achieving efficient and sustainable sediment remediation, including complex sediment environments, interaction mechanisms of biochar-macrophyte-microorganisms, emerging pollutants, and integrated life cycle assessments, which can provide references for combined biochar and plant remediation of sediments in the future.

Noninvasive Evaluation of Renal Hypoxia by Multiparametric Functional MRI in Early Diabetic Kidney Disease.

BACKGROUND: Renal hypoxia, which caused by a mismatch between oxygen delivery and oxygen demand, may be the primary pathophysiological pathway driving diabetic kidney disease (DKD). Blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) could detect hypoxia, but can be limited in distinguishing increased oxygen consumption or decreased blood supply. PURPOSE: To explore multiparametric functional MRI in evaluating mechanism of the hypoxia changes in early stage of DKD. STUDY TYPE: Prospective. ANIMAL MODEL: Thirty-five New Zealand White rabbits were divided into control group (n = 5) and alloxan-induced diabetes mellitus (DM) groups (DM3 group: n = 15, DM7 group: n = 15). FIELD STRENGTH/SEQUENCE: 3 T MRI/BOLD, arterial spin labeling (ASL), and asymmetric spin-echo (ASE). ASSESSMENT: The renal oxygenation level (R2*), renal blood flow (RBF), and oxygen extraction fraction (OEF) were evaluated by BOLD, ASL, and ASE MRI, respectively. The regions of interest were manually drawn including cortex, outer stripes of outer medulla (OS), and inner stripes of outer medulla (IS). STATISTICAL TESTS: Analysis of variance, independent-sample t-test, and paired-sample t-test were applied for comparisons among groups, between groups, and within the same group. P < 0.05 was considered statistically significant. RESULTS: All renal regions of DM3 group at Day 3 after DM induction showed significantly higher R2* and OEF values compared to baseline. The RBF values showed no statistically significant difference (P = 0.62, 0.76, 0.09 in cortex, OS, and IS, respectively). For DM7 group at Day 7, R2*, OEF, and RBF values showed no statistically significant difference compared to baseline (P = 0.06, 0.05, 0.06 of R2*; 0.70, 0.64, 0.68 of OEF; and 0.33, 0.58, 0.48 of RBF in cortex, OS, and IS, respectively). DATA CONCLUSION: BOLD MRI could detect renal hypoxia in early stage of DKD rabbit model, which was mainly revealed by increased oxygen consumption, but not affected by renal blood flow change. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 1.

Tumor Immune Microenvironments (TIMEs): Responsive Nanoplatforms for Antitumor Immunotherapy.

Interest in cancer immunotherapy has rapidly risen since it offers many advantages over traditional approaches, such as high efficiency and prevention of metastasis. Efforts have primarily focused on two major strategies for regulating the body's antitumor immune response mechanisms: "enhanced immunotherapy" that aims to amplify the immune activation, and "normalized immunotherapy" that corrects the defective immune mechanism in the tumor immune microenvironments (TIMEs), which returns to the normal immune trajectory. However, due to the complexity and heterogeneity of the TIMEs, and lack of visualization research on the immunotherapy process, cancer immunotherapy has not been widely used in clinical setting. Recently, through the design and modification of nanomaterials, intelligent TIME-responsive nanoplatforms were developed from which encouraging results in many aspects of immunotherapy have been achieved. In this mini review, the status of designed nanomaterials for nanoplatform-based immune regulation of TIMEs has been emphasized, particularly with respect to the aforementioned approaches. It is envisaged that future prospects will focus on a combination of multiple immunotherapies for more efficient cancer inhibition and elimination.