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Small intestinal health and enteritis incidence are tightly coupled to the homeostasis of intestinal stem cells (ISCs), which are sensitive to dietary alterations. However, little is known about the impact of food additives on ISC pool. Here, we demonstrate that chronic exposure to low‐dose TiO2 NPs, a commonly used food additive, significantly hampers primary human and mouse ISC‐derived organoid formation and growth by specifically attenuating Wnt signal transduction. Mechanistically, TiO2 NPs alter the endocytic trafficking of the Wnt receptor LRP6 and prevent the nuclear entry of β‐catenin. Notably, dietary TiO2 NPs elicit modest chronic stress in healthy intestines and considerably impede the recovery of radiation enteritis by perturbing the homeostasis of ISCs in vivo. Our results identify a health concern of TiO2 NP exposure on ISC homeostasis and radiation enteritis recovery. These findings suggest extra precaution during the treatment of radiation enteritis and provide new insights into food additive‐ISC interaction. [ABSTRACT FROM AUTHOR]

Poly(ADP‐ribosyl)ation (PARylation) is an important post‐translational modification of proteins that involves the transfer of ADP‐ribose moieties, and plays important roles in many biological processes including DNA repair, gene expression, RNA processing, ribosome biogenesis, and protein translation. Though it is accepted that PARylation is crucial for oocyte maturation, little is known about how Mono(ADP‐ribosyl)ation (MARylation) regulates this process. Here, we report that Parp12, a mon(ADP‐ribosyl) transferase of poly(ADP‐ribosyl) polymerase (PARP) family, was highly expressed at all stages of oocytes during meiotic maturation. At germinal vesicle (GV) stage, PARP12 was mainly distributed in cytoplasm. Interestingly, PARP12 formed granular aggregation near to spindle poles during metaphase I (MI) and metaphase II (MII). PARP12 depletion results in abnormal spindle organization and chromosome misalignment in mouse oocytes. Chromosome aneuploidy frequency in PARP12 knockdown oocytes was significantly increased. Importantly, PARP12 knockdown triggers activation of spindle assembly checkpoint as shown by active BUBR1 in PARP12‐KD MI oocytes. Besides, F actin was significantly attenuated in PARP12‐KD MI oocytes which may affect the asymmetric division process. Transcriptomic analysis demonstrated that PARP12 depletion disrupts transcriptome homeostasis. Collectively, our results showed that the maternally expressed mono(ADPribosyl) transferases PARP12 was essential for oocyte meiotic maturation in mouse. [ABSTRACT FROM AUTHOR]

Micro‐/nanorobots have tremendous potential in biomedical applications, as they efficiently and accurately perform local diagnosis and targeted therapy. A magnetic field provides a wireless mean to drive and control micro/nanorobots. This method requires no fuel and is convenient for debugging, reconfiguration, and programmability; it is recyclable and allows nondestructive penetration of biological tissue. The successful integration of well‐designed robots, remote actuation systems, and imaging techniques has become a crucial step toward biomedical applications, particularly in vivo implementations. Herein, the fabrication methods of micro/nanorobots are examined, the driving mechanism of magnetic micro/nanorobots is explained, and the development of micro/nanorobots as transport tools to load and deliver drugs, biological reagents, and live cells is traced. Applications of these micro/nanorobots are expanding as surgical tools for sample collection, ophthalmic surgery, and biofilm degradation and as tools for in vivo and in vitro imaging relying on light, sound, and magnetism. Finally, the challenges faced by micro/nanorobots in in vivo applications and their future prospects are discussed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of early use of ivabradine on left ventricular remodeling after primary percutaneous coronary intervention (PCI) in patients with acute ST‐segment elevation myocardial infarction (STEMI). Methods: A total of 66 STEMI patients with sinus rhythm and the resting heart rate ≥80 bpm after successful emergency PCI were included. The patients in the test group were treated with ivabradine combined with metoprolol at 12 hr after PCI, while the control group was given only metoprolol orally. Their resting heart rate was controlled to <70 bpm at discharge and followed for 180 days. Heart rate and blood pressure were measured regularly. Echocardiogram was performed. N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP), high sensitivity troponin T, high sensitivity troponin I, and high sensitivity C‐reactive protein were measured. The major adverse cardiovascular events during hospitalization and follow‐up period were recorded. Results: Compared with the control group, the heart rate of the test group decreased significantly (p <.05). Compared with the control group, the left ventricular end‐diastolic volume and left ventricular end‐systolic volume were significantly decreased while left ventricular ejection fraction was significantly increased in the test group at 90 days after operation. NT‐proBNP of the test group was significantly lower than that of the control group at 7 days after operation (p <.05). Conclusion: For STEMI patients, early use of ivabradine combined with standard therapy such as β‐blocker after successful reperfusion can achieve effective heart rate control, with great safety and tolerance. But the effect of ivabradine on left ventricular remodeling is uncertain. [ABSTRACT FROM AUTHOR]

Background: The association between macronutrient intake and diabetes is unclear. We used data from the China Health and Nutrition Survey to explore the association between macronutrient intake trajectories and diabetes risk in this study. Methods: We included 6755 participants who did not have diabetes at baseline and participated in at least three surveys. The energy supply ratio of carbohydrate, protein, and fat was further calculated from dietary data; different macronutrient trajectories were determined using multitrajectory models; and multiple Cox regression models were used to evaluate the association between these trajectories and diabetes. Results: We found three multitrajectories: decreased low carbohydrate‐increased moderate protein‐increased high fat (DLC‐IMP‐IHF), decreased high carbohydrate‐moderate protein‐increased low fat (DHC‐MP‐ILF), and balanced‐macronutrients (BM). Compared to the BM trajectory, DHC‐MP‐ILF trajectories were significantly associated with increased risk of diabetes (hazard ratio [HR]: 3.228, 95% confidence interval [CI]: 1.571–6.632), whereas no association between DLC‐IMP‐IHF trajectories and diabetes was found in our study (HR: 0.699, 95% CI: 0.351–1.392). Conclusions: The downward trend of high carbohydrate and the increasing trend of low fat increased the risk of diabetes in Chinese adults. [ABSTRACT FROM AUTHOR]

Summary: Leaf angle is an important agronomic trait in cereals that helps determine plant yield by affecting planting density. However, the regulation mechanism of leaf angle remained elusive.Here, we show that OsbHLH98, a rice bHLH transcription factor, negatively regulates leaf angle. osbhlh98 mutant leaves formed a larger leaf angle, whereas transgenic plants overexpressing OsbHLH98 exhibited a slight reduction in leaf angle.We determined that the changes in leaf angle resulted from increased number and size of parenchyma cells on the adaxial side of the lamina joint in osbhlh98 mutants. Experiments using reporter constructs showed that OsbHLH98 is expressed on the adaxial side of lamina joints, consistent with its proposed function in regulating leaf angle. Furthermore, we established by chromatin immunoprecipitation and CUT&RUN that OsBUL1 is a direct downstream target of OsbHLH98. Transactivation assays and reverse transcription quantitative polymerase chain reaction (RT‐qPCR) analysis indicated that OsbHLH98 represses OsBUL1 transcription.Our results demonstrate that OsbHLH98 negatively regulates leaf angle by counteracting brassinosteroid‐induced cell elongation via the repression of OsBUL1 transcription. The characterization of OsbHLH98 and its role in determining leaf angle will lay the foundation to develop the ideal plant architecture for adaptation to high planting density. [ABSTRACT FROM AUTHOR]