Summary Cystic fibrosis (CF) involves abnormalities in mucus production and secretion of the airway. Studies of the regulation of
airway mucin production and secretion has been difficult due to the lack of in vitro models of the airway epithelial cells
which express functional differentiation. Because the majority of the mucin in the airway is apparently produced by the submucosal
glands, we have focused our attention on the development of cell culture models of human airway submucosal glands. This report
describes the propagation of CF airway submucosal gland epithelial cells which continue to express mucin production. The CF
bronchus was obtained from a 31-yr-old patient who received a double lung transplant. The glands were dissected out and primary
cultures prepared by the explant/outgrowth procedure. The cells were immortalized by infection with Adl2-SV40 hybrid virus.
The cultures are maintained in serum-free keratinocyte basal medium supplemented with insulin (5μg/ml), hydrocortisone (0.5μg/ml), epidermal growth factor (10 ng/ml), bovine pituitary extract (25μg/ml), and antibiotics. Cultures were passaged using 0.125% trypsin in Ca+2 and Mg+2-free Hanks’, balanced salt solution. Polymerase chain reaction (PCR) analysis demonstrated that the cells were homozygous
for the ΔF508 mutation. Morphologic observations showed that the cells were epithelial and were interconnected by sparsely
distributed desmosomes. Their cytoplasm contained secretory-type structures including abundant Golgi, rough endoplasmic reticulum,
and secretory vesicles. Immunofluorescent studies determined that all cells were positive for cytokeratins, mucin glycoconjugates,
and cystic fibrosis transmembrane conductance regulator. The cultures secreted substantial amounts of mucin glycoproteins
and expressed the MUC-2 mucin gene. Patch clamp experiments revealed that the cells expressed defective Cl− channels which were not activated by Forskolin. 相似文献
Human mononuclear cells pre-labeled with [3H]arachidonic acid were shown to release metabolites following in vitro addition of heat-killed Salmonella typhi (HKST). The amount of label released was significantly higher than that seen with live S. typhi (LST). Addition of increasing amounts of HKST resulted in an increased release of metabolites. Enzyme immunoassay of the culture supernatants revealed that the bulk of the metabolite released was prostaglandin E2 (PGE2). Leukotriene B4 (LTB4) and leukotriene C4 (LTC4) were not detectable in the culture supernatants. The significance and implications of these results are discussed. 相似文献
Acute liver failure (ALF) is an inflammation-mediated hepatocyte death process associated with ferroptosis. Avicularin (AL), a Chinese herbal medicine, exerts anti-inflammatory and antioxidative effects. However, the protective effect of AL and the mechanism on ALF have not been reported. Our in vivo results suggest that AL significantly alleviated lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced hepatic pathological injury, liver enzymes, inflammatory cytokines, reactive oxygen species and iron levels and increased the antioxidant enzyme activities (malondialdehyde and glutathione). Our further in vitro experiments demonstrated that AL suppressed inflammatory response in LPS-stimulated RAW 264.7 cells via blocking the toll-like receptor 4 (TLR4)/myeloid differentiation protein-88 (MyD88)/nuclear factor kappa B (NF-κB) pathway. Moreover, AL attenuated ferroptosis in D-GalN-induced HepG2 cells by activating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1)/glutathione peroxidase 4 (GPX4) pathway. Therefore, AL can alleviate inflammatory response and ferroptosis in LPS/D-GalN-induced ALF, and its protective effects are associated with blocking TLR4/MyD88/NF-κB pathway and activating Nrf2/HO-1/GPX4 pathway. Moreover, AL is a promising therapeutic option for ALF and should be clinically explored. 相似文献
Few approaches have been conducted in the treatment of renal cell carcinoma (RCC) after nephrectomy, resulting in a high mortality rate in urological tumours. Mitophagy is a mechanism of mitochondrial quality control that enables selective degradation of damaged and unnecessary mitochondria. Previous studies have found that glycerol-3-phosphate dehydrogenase 1-like (GPD1L) is associated with the progression of tumours such as lung cancer, colorectal cancer and oropharyngeal cancer, but the potential mechanism in RCC is still unclear. In this study, microarrays from tumour databases were analysed. The expression of GPD1L was confirmed by RT–qPCR and western blotting. The effect and mechanism of GPD1L were explored using cell counting kit 8, wound healing, invasion, flow cytometry and mitophagy-related experiments. The role of GPD1L was further confirmed in vivo. The results showed that GPD1L expression was downregulated and positively correlated with prognosis in RCC. Functional experiments revealed that GPD1L prevented proliferation, migration and invasion while promoting apoptosis and mitochondrial injury in vitro. The mechanistic results indicated that GPD1L interacted with PINK1, promoting PINK1/Parkin-mediated mitophagy. However, inhibition of PINK1 reversed GPD1L-mediated mitochondrial injury and mitophagy. Moreover, GPD1L prevented tumour growth and promoted mitophagy by activating the PINK1/Parkin pathway in vivo. Our study shows that GPD1L has a positive correlation with the prognosis of RCC. The potential mechanism involves interacting with PINK1 and regulating the PINK1/Parkin pathway. In conclusion, these results reveal that GPD1L can act as a biomarker and target for RCC diagnosis and therapy. 相似文献
Motivated by investigating the relationship between progesterone and the days in a menstrual cycle in a longitudinal study, we propose a multikink quantile regression model for longitudinal data analysis. It relaxes the linearity condition and assumes different regression forms in different regions of the domain of the threshold covariate. In this paper, we first propose a multikink quantile regression for longitudinal data. Two estimation procedures are proposed to estimate the regression coefficients and the kink points locations: one is a computationally efficient profile estimator under the working independence framework while the other one considers the within-subject correlations by using the unbiased generalized estimation equation approach. The selection consistency of the number of kink points and the asymptotic normality of two proposed estimators are established. Second, we construct a rank score test based on partial subgradients for the existence of the kink effect in longitudinal studies. Both the null distribution and the local alternative distribution of the test statistic have been derived. Simulation studies show that the proposed methods have excellent finite sample performance. In the application to the longitudinal progesterone data, we identify two kink points in the progesterone curves over different quantiles and observe that the progesterone level remains stable before the day of ovulation, then increases quickly in 5 to 6 days after ovulation and then changes to stable again or drops slightly. 相似文献
Continuous cropping (CC) obstacle is a major threat in legume crops production; however, the underlying mechanisms concerning the roles allelochemicals play in CC obstacle are poorly understood. The current 2-year study was conducted to investigate the effects of different kinds and concentrations of allelochemicals, p-hydroxybenzoic acid (H), cinnamic acid (C), phthalic acid (P), and their mixtures (M) on peanut root growth and productivity in response to CC obstacle. Treatment with H, C, P, and M significantly decreased the plant height, dry weight of the leaves and stems, number of branches, and length of the lateral stem compared with control. Exogenous application of H, C, P, and M inhibited the peanut root growth as indicated by the decreased root morphological characters. The allelochemicals also induced the cell membrane oxidation even though the antioxidant enzymes activities were significantly increased in peanut roots. Meanwhile, treatment with H, C, P, and M reduced the contents of total soluble sugar and total soluble protein. Analysis of ATPase activity, nitrate reductase activity, and root system activity revealed that the inhibition effects of allelochemicals on peanut roots might be due to the decrease in activities of ATPase and NR, and the inhibition of root system. Consequently, allelochemicals significantly decreased the pod yield of peanut compared with control. Our results demonstrate that allelochemicals play a dominant role in CC obstacle-induced peanut growth inhibition and yield reduction through damaging the root antioxidant system, unbalancing the osmolytes accumulation, and decreasing the activities of root-related enzymes.