Astrocyte KDM4A mediates chemokines and drives neutrophil infiltration to aggravate cerebral ischemia and reperfusion injury

Neutrophils plays a crucial role in acute ischemic brain injury and have emerged as potential treatment targets to mitigate such injuries. Lysine-specific demethylase 4 A (KDM4A), a member of the histone lysine demethylase family of enzymes involved in transcriptional regulation of gene expression, is upregulated during hypoxic events. However, the exact role of KDM4A in the pathological process of ischemic stroke remains largely unexplored. Our findings reveal that there was an upregulation of KDM4A levels in reactive astrocytes within both stroke mouse models and in vitro oxygen-glucose deprivation/regeneration (OGD/R) models. Using a conditional knockout mouse, we observed that astrocytic Kdm4a knockout regulates neutrophil infiltration and alleviates brain injury following middle cerebral artery occlusion reperfusion. Furthermore, Kdm4a deficiency astrocytes displayed lower chemokine C-X-C motif ligand 1 (CXCL1) level upon OGD/R and decreased neutrophil infiltration in a transwell system. Mechanistically, KDM4A, in cooperation with nuclear factor-kappa B (NF-κB), activates Cxcl1 gene expression by demethylating histone H3 lysine 9 trimethylation at Cxcl1 gene promoters in astrocytes upon OGD/R injury. Our findings suggest that astrocyte KDM4A-mediated Cxcl1 activation contributes to neutrophil infiltration via cooperation with NF-κB, and KDM4A in astrocytes may serve as a potential therapeutic target to modulate neutrophil infiltration after stroke.

Identification of genes related to floral organ development in pak choi by expression profiling

Pak choi is a highly nutritious vegetable that is widely grown in China, Southeast Asia, and other parts of the world. Because it reproduces by seed, it is very important to understand the mechanism of floral organ development. Therefore, using the Chinese cabbage genome as a reference, this study analyzed the expression profiles of shoot apex genes at flower bud differentiation stages 1 and 5, in order to identify genes related to floral organ development. The results showed that the proportion of mapped genes was high, with 84.25 and 83.80% of clean reads from the two sample saligned to the reference genome, respectively. A total of 525 differentially expressed genes (DEGs) were identified, 224 of which were upregulated and 301 were downregulated. The expression levels of genes homologous to Chinese cabbage flowering genes were also analyzed at stages 1 and 5; the expression levels of Bra012997 (ap1), Bra000393 (SOC1), and Bra004928 (SOC1) were significantly upregulated at stage 5, suggesting that these three genes positively regulate floral development in pak choi. DEGs involved in floral organ development were analyzed with homologous genes from Arabidopsis thaliana; the homologous genes Bra029281 (AGL42), Bra026577 (ARPN), Bra022954 (SPL3), Bra029293 (ARF2), Bra007978 (AtRLP12), Bra033221 (SPL8), Bra008037 (LOX4), Bra001598 (IAA19), Bra003892 (PATL1), Bra038778 (AT4G21323), Bra025315 (KLCR2), and Bra013906 (DTX35) are directly related to floral organ development in Arabidopsis, suggesting that these genes have corresponding functions during flower organ development in pak choi, and could be candidates for further genetic research. These results provide a foundation for research on the molecular mechanism of flower organ development in pak choi and other Brassica rapa vegetables.

Quantitative trait locus analysis for kernel width using maize recombinant inbred lines

Maize (Zea mays L.) kernel width is one of the most important traits that is related to yield and appearance. To understand its genetic mechanisms more clearly, a recombinant inbred line (RIL) segregation population consisting of 239 RILs was used for quantitative trait locus (QTL) mapping for kernel width. We found four QTLs on chromosomes 3 (one), 5 (two), and 10 (one). The QTLs were close to their adjacent markers, with a range of 0-23.8 cM, and explained 6.2-19.7% of the phenotypic variation. The three QTLs on chromosomes 3 and 5 had positive additive effects, and to a certain extent increased kernel width, whereas the one on chromosome 10 exhibited negative additive effects and decreased kernel width. These results can be used for gene cloning and marker-assisted selection in maize-breeding programs.

Eosinophil cationic protein mRNA expression in children with bronchial asthma

Studies have shown that eosinophils are closely related to pathogenesis of bronchial asthma. Eosinophils release eosinophil cationic protein (ECP), which plays an important role in infection and allergic reactions. Serum ECP mRNA expression in children with bronchial asthma has not been adequately investigated. We analyzed serum ECP mRNA expression in 63 children with bronchial asthma and 21 healthy children by using reverse-transcriptase polymerase chain reaction to understand the role of ECP in children with bronchial asthma. The children with bronchial asthma were segregated into acute-phase and stable-phase groups, based on the severity of the illness. Serum ECP mRNA expression in children with bronchial asthma (0.375 ± 0.04) was significantly higher than that in healthy controls (0.20 ± 0.02; P < 0.05). Additionally, children in the acute-phase group showed higher ECP mRNA expression level (0.44 ± 0.06) than those in the stable-phase (0.31 ± 0.03) and healthy control groups (0.20 ± 0.02; P < 0.05), while the level in the stable-phase (0.31 ± 0.03) was markedly higher than that in the healthy control group (0.20 ± 0.02; P < 0.05). Detection of serum ECP mRNA expression level has possible applications in the diagnosis and treatment of children with bronchial asthma.

Related factors and prevalence of Parkinson's disease among Uygur residents in Hetian, Xinjiang Uygur Autonomous Region

The aim of this study was to identify the factors related to and determine the prevalence of Parkinson's disease (PD) among Uygur residents in Hetian Prefecture, Xinjiang Uygur Autonomous Region. This population-based prospective cohort study used structured questionnaires to screen for factors related to PD. The prevalence in different age groups was analyzed, and PD risk was assessed using univariate and multivariate conditional logistic regression analysis. In total, 5932 subjects participated in the survey; of these, 88 individuals, all of whom were Uygurs, had PD. The overall prevalence of PD was 1.48% (1.32%) in people over the age of 45; the prevalence was 1.68% (1.59%) in men and 1.28% (1.36%) in women. The Fifth Population Census in China found the prevalence of PD in Hetian, Xinjiang, to be 1.32%. Single-factor results showed that exercise, social activities, and frequent consumption of nuts are protective factors for PD, and long-term pesticide exposure, family history of PD, and consumption of barbecued food were risk factors for this condition. Multi-factor conditional logistic regression analysis showed that participation in sports and social activities can reduce the risk of PD, whereas long-term pesticide exposure and family history of PD increases this risk. These results show that PD is caused by the interaction of several factors.

Autophagy inhibition contributes to radiation sensitization of esophageal squamous carcinoma cells

Radiotherapy is a useful component of treatment strategies for esophageal cancer. The role of autophagy in response to ionizing radiation was investigated in human esophageal squamous carcinoma cells. Cell viability and clonogenic survival assay were used to evaluate the radiosensitivity of autophagy inhibitor (3-MA) on esophageal squamous carcinoma cells. The percentage of apoptotic cells and cell cycle analysis were assessed by flow cytometry; DAPI staining was used to detect apoptotic cells. The expression of beclin-1 and LC3 was measured using a Western blot. The ultrastructural analysis was under the electron microscope. 6 Gy irradiation induced a massive accumulation of autophagosomes accompanied by strong upregulation of beclin-1 and LC3-II expression in TE-1 cells. Compared with radiation alone, 3-MA combined with radiation significantly decreased cell viability, as well as autophagic ratio, beclin-1, and LC3-II protein level. Inhibition of autophagy increased radiation-induced apoptosis and the percentage of G2/M-phase cells. Blockade of autophagy with 3-MA enhanced cytotoxicity of radiotherapy in human esophageal squamous carcinoma cells. It suggests that inhibition of autophagy could be used as adjuvant therapy to treat esophageal squamous cell carcinoma.

[Effect of anticancer polypeptide from Buthus Martensii venom on immune function in the H22-bearing mice]

OBJECTIVE

To observe the effect of anticancer polypeptide from Buthus Martensii Venom (APBMV) on Immune function in the H22-bearing mice.

METHODS

The MTT colorimetric method, homolysin assay, lymphocyte transformation test, delayed hypersensitivity assay and WBC-count of peripheral blood were used in this study.

RESULTS

APBMV could obviously augment NK activity, promote proliferation of lymphocytes induced by Con A, potentiate the response of DTH induced by DNCB, antagonize the decrease of WBC in peripheral blood induced by 5-Fu in the H22-bearing mice.

CONCLUSION

APBMV can obviously increase immune function in the H22-bearing mice and antagonize hypoimmunity immunodeficiency or immunodeficiency induced by chemotherapy or the tumor.