ABSTRACT
A leaf structure with high porosity is beneficial for lateral CO2 diffusion inside the leaves. However, the leaf structure of maize is compact, and it has long been considered that lateral CO2 diffusion is restricted. Moreover, lateral CO2 diffusion is closely related to CO2 pressure differences (ΔCO2). Therefore, we speculated that enlarging the ΔCO2 between the adjacent regions inside maize leaves may result in lateral diffusion when the diffusion resistance is kept constant. Thus, the leaf structure and gas exchange of maize (C4), cotton (C3), and other species were explored. The results showed that maize and sorghum leaves had a lower mesophyll porosity than cotton and cucumber leaves. Similar to cotton, the local photosynthetic induction resulted in an increase in the ΔCO2 between the local illuminated and the adjacent unilluminated regions, which significantly reduced the respiration rate of the adjacent unilluminated region. Further analysis showed that when the adjacent region in the maize leaves was maintained under a steady high light, the photosynthesis induction in the local regions not only gradually reduced the ΔCO2 between them but also progressively increased the steady photosynthetic rate in the adjacent region. Under field conditions, the ΔCO2, respiration, and photosynthetic rate of the adjacent region were also markedly changed by fluctuating light in local regions in the maize leaves. Consequently, we proposed that enlarging the ΔCO2 between the adjacent regions inside the maize leaves results in the lateral CO2 diffusion and supports photosynthesis in adjacent regions to a certain extent under fluctuating light.
Subject(s)
Carbon Dioxide , Zea mays , Carbon Dioxide/pharmacology , Light , Photosynthesis , Plant Leaves , DiffusionABSTRACT
Chlorophyll a fluorescence induction kinetics (CFI) is an important tool that reflects the photosynthetic function of leaves, but it remains unclear whether it is affected by leaf structure. Therefore, in this study, the leaf structure and CFI curves of sunflower and sorghum seedlings were analyzed. Results revealed that there was a significant difference between the structures of palisade and spongy tissues in sunflower leaves. Their CFI curves, measured on both the adaxial and abaxial sides, also differed significantly. However, the differences in the leaf structures and CFI curves between both sides of sorghum leaves were not significant. Further analysis revealed that the differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves almost disappeared due to reduced incident light scattering and refraction in the leaf tissues; more importantly, changes in the CFI curves of the abaxial side were greater than the adaxial side. Compared to leaves grown under full sunlight, weak light led to decreased differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves; of these, changes in the CFI curves and palisade tissue structure on the adaxial side were more obvious than on the abaxial side. Therefore, it appears that large differences in sunflower leaf structures may affect the shape of CFI curves. These findings lay a foundation for enhancing our understanding of CFI from a new perspective.
Subject(s)
Helianthus , Chlorophyll A/analysis , Plant Leaves/chemistry , Photosynthesis , Fluorescence , Chlorophyll/analysisABSTRACT
Duodenal duplication is a rare congenital anomaly and may manifest as pancreatitis, gastrointestinal bleeding, abdominal pain, perforation, and obstruction. Here, we present a case of intraluminal diverticular duodenal duplication (IDDD) in a child with recurrent abdominal pain caused by a large hole-like structure in the duodenal bulb. This condition has rarely been reported. An 11-year-old boy presented with recurrent attacks of abdominal pain. Upper endoscopy examination and barium swallowing led to an initial diagnosis of IDDD; this diagnosis was confirmed by operative findings and histopathological signs. He underwent a subtotal excision and duodenal anastomosis. No serious complications occurred following treatment. The patient was followed up for 8 months, and his condition improved without symptoms.
ABSTRACT
Abdominal aortic aneurysm (AAA) is a chronic dilated disease of the aorta that is characterized by chronic inflammation. Curcumin (Cur) is previously showed to attenuate AAA by inhibiting inflammatory response in ApoE -/- mice. Since Cur has the limitations of aqueous solubility and instability. Here, we focus on the role of curcumin nicotinate (CurTn), a Cur derivative is derived from Cur and nicotinate. An in vitro model of AAA was established by treating vascular smooth muscle cells (VSMCs) with II (Ang-II). Gene and protein expressions were examined by quantitative real-time PCR (qPCR) or western blotting. Cell migration and pyroptosis were determined by transwell assay and flow cytometry. The interaction between plasmacytoma variant translocation 1 (PVT1), miR-26a and krüppel-like factor 4 (KLF4) was predicted by online prediction tool and confirmed by luciferase reporter assay. CurTn reduced Ang-II-induced AAA-associated proteins, inflammatory cytokine expressions, and attenuated pyroptosis in VSMCs. PVT1 overexpression suppressed the inhibitory effect of CurTn on AngII-induced pyroptosis and inflammatory in VSMCs by sponging miR-26a. miR-26a directly targeted KLF4 and suppressed its expression, which eventually led to the deactivation of the PI3K/AKT signaling pathway. Besides, the regulatory effect of CurTn on pyroptosis of VSMCs induced by Ang-II was reversed through the PVT1/miR-26a/KLF4 pathway. In short, CurTn suppressed VSMCs pyroptosis and inflammation though mediation PVT1/miR-26a/KLF4 axis by regulating the PI3K/AKT signaling pathway, CurTn might consider as a potential therapeutic target in the treatment of AAA.
ABSTRACT
Objective: This study investigated the expression and clinical value of hsa-miR-504 in cervical cancer and its possible mechanism of regulating the progress of cervical cancer. Methods: The expression of microRNAs (miRNAs) in cervical cancer was analyzed on The Cancer Genome Atlas (TCGA) database. The correlation between differentially expressed miRNAs and overall survival (OS) of cervical cancer patients was analyzed by Kaplan-Meier method. The target genes regulated downstream by hsa-miR-504 were predicted by miRWalk 2.0 and analyzed by Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) after differential screening. Univariate and multivariate Cox regressions were performed to screen the prognosis-related target genes. Results: There were 82 differentially expressed miRNAs between cervical cancer and noncancerous tissues in TCGA database (fold change >2, p < 0.05). Among them, nine miRNAs, including hsa-miR-504, were significantly correlated with OS in cervical cancer patients. Hsa-miR-504 was downregulated in cervical cancer, and low hsa-miR-504 expression was associated with poor prognosis. There were 2670 target genes of hsa-miR-504, and 240 target genes were further confirmed to be upregulated by TCGA database (fold change >2, p < 0.05). GO and KEGG showed that the upregulated target genes were mainly enriched in cell cycle, DNA replication, p53 signaling pathway, and so on. Kaplan-Meier survival analysis showed that 21 target genes were associated with OS in cervical cancer patients (p < 0.05). Univariate and multivariate Cox regression analysis showed that five genes were independent prognostic factors in cervical cancer. Conclusion: The low expression of hsa-miR-504 was closely related to the occurrence and development of cervical cancer, and hsa-miR-504 might be a potential molecular marker for favorable prognosis in cervical cancer. Cell cycle, DNA replication, and p53 signaling pathway were important mechanisms of downregulated hsa-miR-504 involved in the occurrence and development of cervical cancer.
