l-Carnosine Protects Against Deoxynivalenol-Induced Oxidative Stress in Intestinal Stem Cells by Regulating the Keap1/Nrf2 Signaling Pathway.

SCOPE: The intestinal epithelium is nourished by various nutrients and subjected to persistent and widespread feed-derived mycotoxin stress. l-Carnosine (LC) possesses robust antioxidant activity; however, its role in protecting intestinal mucosa against deoxynivalenol (DON) is still unclear. METHODS AND RESULTS: In this study, 300 mg kg-1 BW LC and 3 mg kg-1 BW DON are orally administered to mice either alone or in combination for 10 days to investigate the role of LC in protecting the intestine against DON. This study found that LC alleviates the growth retardation of mice and repairs the damaged jejunal structure and barrier functions under DON exposure. LC rescues the intestinal stem cells (ISCs), increases the growth advantage in enteroids derived from jejunal crypts of mice in each group ex vivo, improves the proliferation and apoptosis of intestinal cells, and promotes ISC differentiation into absorptive cells, goblet cells, and Paneth cells. Furthermore, LC activates Nrf2 signaling by binding to Keap1 to reverse the striking DON-induced increase in ROS levels. CONCLUSION: The study findings unveil that LC potentiates the antioxidant capacity of ISCs by regulating the Keap1/Nrf2 signaling pathway, which contributes to the intestinal epithelial regeneration response to DON insult.

Zinc L-Aspartate enhances intestinal stem cell activity to protect the integrity of the intestinal mucosa against deoxynivalenol through activation of the Wnt/ß-catenin signaling pathway.

The micronutrient, zinc, plays a vital role in modulating cellular signaling recognition and enhancing intestinal barrier function. However, the precise mechanisms underlying the zinc regulation of intestinal stem cell (ISC) renewal and regeneration ability, which drive intestinal epithelial turnover to maintain the intestinal barrier, under physiological and pathological conditions are unknown. In this study, we used in vivo mouse plus ex vivo enteroid model to investigate thoroughly the protection efficacy of zinc L-aspartate (Zn-Asp) on intestinal mucosal integrity exposed to deoxynivalenol (DON). The results showed that 10 rather than 20 mg/kg body weight (BW) Zn-Asp (calculation in zinc) significantly increased the jejunum mass and ameliorated mucosa injury caused by 2 mg/kg BW DON treatment, including improvement of the intestinal morphology and barrier, as well as enteroid-forming and -budding efficiency, which was expanded from crypt cells isolated from jejunum of mice in each group. The repair process stimulated by Zn-Asp was also accompanied by increased fluorescence signal intensity of KRT20 and Villin; increased numbers of MUC2+, CAG+, LYZ+, BrdU+ and Ki67+ cells in mouse jejunum; and protein expression of Ki67 and PCNA in the jejunum, crypt and enteroid. Simultaneously, Zn-Asp increased ISC activity to promote intestinal epithelial renewal even under physiological conditions. These results were further verified in ex vivo enteroid culture experiments, which were treated with 100 µmol/L Zn-Asp (calculation in zinc) and 100 ng/mL DON for 72 h. Furthermore, we demonstrated that Zn-Asp improved intestinal integrity or accelerated wound healing along with Wnt/ß-catenin signaling upregulation or reactivation. Our findings indicate Zn-Asp, especially Zn, enhances ISC activity to maintain the intestinal integrity by activating the Wnt/ß-catenin signaling, which sheds some light upon effective preventive strategies for intestinal injury induced by mycotoxin based on ISCs with exogenous zinc preparations in the proper drugs, health foods or qualified feed.

Methionine and Its Hydroxyl Analogues Improve Stem Cell Activity To Eliminate Deoxynivalenol-Induced Intestinal Injury by Reactivating Wnt/ß-Catenin Signaling.

The intestinal epithelium is derived from intestinal stem cells (ISCs) and has direct contact with nutrients and toxins. However, whether methionine (Met) or a methionine hydroxyl analogue (2-hydroxy-4-(methylthio)butanoic acid (HMB)) can alleviate deoxynivalenol (DON)-induced intestinal injury remains unknown. Mice were treated orally with Met or HMB on days 1-11 and with DON on days 4-8. On day 12, the mice were sacrificed, and the jejunum was collected for crypt isolation and culture. Mouse enteroids were treated with DON and Met or HMB ex vivo. The results showed that Met and HMB increased the average daily feed intake and average daily gain of the mice. Met and HMB also improved the jejunal structure and barrier integrity and promoted ISC expansion, as indicated by the increased enteroid formation efficiency and area, under DON-induced injury conditions. In addition, DON-induced decreases in ISC activity were rescued Wnt/ß-catenin signaling reactivation by Met or HMB in vivo and ex vivo. Collectively, our findings reveal that Met and HMB alleviated DON-induced intestinal injury by improving ISC expansion and reactivating Wnt/ß-catenin signaling. Our study thus provides a nutritional intervention for intestinal diseases involving Wnt/ß-catenin signaling.

Hydrolyzed wheat gluten alleviates deoxynivalenol-induced intestinal injury by promoting intestinal stem cell proliferation and differentiation via upregulation of Wnt/ß-catenin signaling in mice.

Disintegration of the intestine caused by deoxynivalenol (DON), which is a fungal metabolite found in cereal grain-based human and animal diets, triggers severe intestinal inflammatory disease. Hydrolyzed wheat gluten (HWG) can promote the development of intestine. Therefore, HWG was administered orally to male mice on 1-14 days, and DON was administered to them on 4-11 days. Feed, water intake and body weight were recorded all over the experimental period. Blood samples were collected then the mice were sacrificed to collect the jejunum for crypt isolation and culture. The intestinal morphology was observed by electron microscopy, and Western blotting was used to investigate intestinal stem cell (ISC) proliferation and differentiation, as well as the primary regulatory mechanism of the Wnt/ß-catenin signaling. The results showed that HWG increased the average daily gain and average daily water intake of mice under DON-induced injury conditions, and increased the jejunum weight, villous height in the jejunum, and promoted jejunal crypt cell expansion. The DON-induced decrease in Wnt/ß-catenin activity, the expression of Ki67, PCNA and KRT20 were rescued by HWG in the jejunum, crypt and enteroid, as well as the number of goblet cells and Paneth cells. Furthermore, HWG increased jejunum diamine oxidase (DAO) activity. In conclusion, HWG alleviates DON-induced intestinal injury by enhancing ISC proliferation and differentiation in a Wnt/ß-catenin-dependent manner.

Prenatal counseling strategies for two cases with maternal uterine cavity abnormalities and misshapen fetal head detected in the third trimester / 中国实用妇科与产科杂志

OBJECTIVE:To discuss the clinical strategies of prenatal counseling in cases with abnormal maternal uterus cavity and misshapen fetal head detected in the third trimester.METHODS:The cases with both maternal uterus malforma⁃tion and ultrasound-diagnosed microcephaly only at the third trimester between 2016 and 2017 were reviewed and the postnatal development of the infants was followed up.RESULTS:A total of two cases were recruited and both cases showed normal fetal structure at the second trimester anomaly scan.One case was noted to have board thick fibromuscular adhe⁃sions band.The fetus was in breech presentation with limited fetal movement of the lower limbs.Amniocenetesis revealed normal karyotype of the fetus.At the 31 st week of the gestation,the fetus appeared to have elongated head with head cir⁃cumference(HC)at-2 SD level,protruding upper lip,and unilateral club foot.The other pregnant woman had complete uterine septum with fundus-located placenta and breech presentation.Her fetus had a HC below-4 SD whereas the dis⁃tance between the cranial bottom to top was 88 mm,with caput succedaneum and oligohydramnios.Magnetic resonance im⁃aging(MRI)showed normal structure and sulci gyrus development of the fetus.Both babies were born prematurely(at36 th and 31 st week)with birth weights compatible to their gestational ages,and both had an obviously misshapen head at birth.One baby also had unilateral club foot.The babies' appearance and development were totally normal at a follow-up examination at 6 months after birth.CONCLUSION:The prognosis of cases with uterine cavity abnormality and misshapen fetal head detected only at third trimester is usually good,but there is increased risk of malpresentation and preterm la⁃bor.Comprehensive assessment of the serial fetal growth conditions,maternal uterus abnormalities,and MRI are helpful in prenatal counseling.

Iron Nanoclusters as Template/Activator for the Synthesis of Nitrogen Doped Porous Carbon and Its CO2 Adsorption Application.

We propose a facile synthesis approach for nitrogen doped porous carbon and demonstrate a novel pore-forming method that iron nanoclusters act as a template or activator at different carbonization temperatures based on Fe3+-poly(4-vinyipyridine) (P4VP) coordination. P4VP will completely decompose even in an inert atmosphere, but under the coordination and catalysis of Fe3+, it can be converted to carbon at a very low temperature (400 °C). The aggregation of iron nanoclusters in the carbonization process showed different pore-forming methods at different temperatures. The as-prepared materials possess high specific surface area (up to 1211 m2 g-1), large pore volume (up to 0.96 cm3 g-1), narrow microporosity, and high N content (up to 9.9 wt %). Due to these unique features, the materials show high CO2 uptake capacity and excellent selectivity for CO2/N2 separation. The CO2 uptake capacity of NDPC-2-600 is up to 6.8 and 4.3 mmol g-1 at 0 and 25 °C; the CO2/N2 (0.15/0.85) selectivity at 0 and 25 °C also reaches 18.4 and 15.2, respectively.

Analysis of CYP21A2 gene mutation in one case of congenital adrenal hyperplasia / 中国当代儿科杂志

CYP21A2 gene mutations in a child with congenital adrenal hyperplasia (CAH), and the child's parents, were detected in the study. The clinical features, treatment monitoring and molecular genetic mechanism of CAH are reviewed. In the study, DNA was extracted from peripheral blood samples using the QIAGEN Blood DNA Mini Kit; a highly specific PCR primer for CYP21A2 gene was designed according to the sequence difference between CYP2lA2 gene and its pseudogene; the whole CYP2lA2 gene was amplified with PrimeSTAR DNA polymerase (Takara), and the amplification product was directly sequenced to detect and analyze CYP2lA2 gene mutation. The child was clinically diagnosed with CAH (21-hydroxylase deficiency, 21-OHD) at the age of 36 days, and the case was confirmed by genetic diagnosis at the age of 1.5 years. The proband had a homozygous mutation at c.293-13C in the second intron of CYP21 gene, while the parents had heterozygous mutations. Early diagnosis and standard treatment of CAH (21-OHD) should be performed to prevent salt-wasting crisis and reduce mortality; bone aging should be avoided to increase final adult height (FAH), and reproductive dysfunction due to oligospermia in adulthood should be avoided. These factors are helpful for improving prognosis and increasing FAH. Investigating the molecular genetic mechanism of CAH can improve recognition and optimize diagnosis of this disease. In addition, carrier diagnosis and genetic counseling for the proband family are of great significance.

Cell-free fetal DNA detection in maternal plasma using real-time PCR and cycling probe technology for prenatal screening beta-thalassaemia major / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze cell-free fetal DNA in maternal plasma for prenatal screening of beta-thalassaemia major.</p><p><b>METHODS</b>Six couples undergoing prenatal diagnosis of beta-thalassaemia (gestational age range 23-26 weeks) were enrolled in this study. The husbands were all carriers of the CD17 (A-->T) mutation, and the wives carried another beta-thalassaemia mutation. The allele-specific primers and two fluorescent cycling probes were synthesized for the detection of the CD17 (A-->T) mutation, using FAM and HEX fluorescence labeling, respectively. The cell-free fetal DNA in the maternal plasma was detected using real-time PCR, and the fetal genotype was confirmed by cord blood conventional prenatal diagnosis.</p><p><b>RESULTS</b>In the 6 pregnancies, FAM and HEX fluorescent signals were detected in 3 maternal plasma samples; in the other 3 samples, only FAM fluorescent signals were detected, suggesting the absence of paternally derived CD17 (A-->T) mutation.</p><p><b>CONCLUSION</b>Examination of cell-free fetal DNA in maternal plasma using real-time PCR and cycling probe technology can be effective means for prenatal screening of beta-thalassaemia major.</p>