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1.
Stimulation of the neonatal immune system is quite important for the proliferation and differentiation of antigen-presenting cells (APCs) and T cells. Tahneeq is a traditional method to manually rub the palatal mucosa of newborn babies with premasticated Ajwa palm dates. The present study was to investigate the tahneeq effects on IL-12 expression of dendritic cells (DCs) and blood T lymphocytes expressing CD8+ in neonatal Wistar rats. The number of 90 healthy neonatal Wistar rats have randomly divided into three groups: control group received breastmilk only, treatment group (T1) receiving breast milk + mild-scratched intensity of tahneeq, and T2 group received breastmilk + strong-scratched intensity of tahneeq on the palatal and gingival mucosa immediately after birth.  Seven neonatal Wistar rats in all groups were then sacrificed in three hours after birth and days 1, 5, 7, 13, and 30 treatment. IL-12 expression in the palatal and gingival mucosa was determined using immunohistochemical staining, and blood CD8+ T-lymphocytes were quantified using a flow cytometer. One way ANOVA was used to analyze the percentage of IL-12 and CD8+ T-lymphocytes among neonatal Wistar rat groups.  The T1 and T2 newborn rat groups had significantly higher IL-12 expression than the control group (p<0.001). The increased IL-12 expression in T2 groups significantly increased (p<0.001) compared to the IL-12 expression in the T1 and control groups. The percentage of  CD8+ T lymphocytes in all neonatal rat groups increased on three hours after birth and day 30 treatment but remained constant on days 5 and 7 treatment and decreased on day 13 treatment. At 5, 13, and 30th days treatment,  the percentage of CD8+ T lymphocytes in T1 and T2 neonatal rat groups was significantly higher (p<0.05) than that in the control group. In conclusion, the impact on systemic CD8+ T cells did not influence by the depth of the scratch. Both mild and strong tahneeq increased the systemic CD8+ T-lymphocytes in neonatal Wistar rats. The roles of anti-inflammatory cytokines and Treg cells should be further investigated to unravel those different results for the development of mucosal immunity in neonates.  相似文献   
2.
The mycorrhizal mycoflora was investigated in 35 stands of Pinus sylvestris in three types of young (4-13 yr) and three of old (50-80 yr) stands in the Netherlands, differing in number of rotations and soil type. A plot of 1050 m2 (30 m x 35 m) within each stand was searched for carpophores during the autumns of 1986 and 1987. 10 soil samples per plot were taken in October 1987 in order to assess the mycorrhizal status of the tree roots. The composition of mycorrhizal mycoflora in the different plots was subjected to TWINSPAN cluster analysis and Detrended Correspondence Analysis. Plot groupings generated by these analyses largely parallelled the stand types, indicating that each stand type has its own mycoflora. Differences in myco-floristic composition between stand types were parallelled by differences in the composition of green vegetation. The young stand types had 3.5–27 x more carpophores and 1.4–6.8 x more species than two of the old stand types One old stand type was intermediate. Considerable differences in species composition between the young stand types were observed. It is concluded that the succession of mycorrhizal fungi is not primarily influenced by ageing of the trees, but rather by changes in the soil. The results were compared with data on changes in the occurrence of fruiting species of mycorrhizal fungi in the Netherlands during this century. It appeared that species which have declined according to these data were more frequent in the young plots than in the old plots. However, these species are reported to be frequent in old stands of P. sylvestris in Estonia and Finland. It is argued that this difference is related to the high nitrogen deposition in the Netherlands.  相似文献   
3.
《Developmental cell》2023,58(10):866-884.e8
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4.
Volatile chemicals in the environment provide ethologically important information to many animals. However, how animals learn to use this information is only beginning to be understood. This review highlights recent experimental advances elucidating olfactory learning in rodents, ranging from adaptations to the environment to task-dependent refinement and multisensory associations. The broad range of phenomena, mechanisms, and brain areas involved demonstrate the complex and multifaceted nature of olfactory learning.  相似文献   
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A highly sensitive and selective method for determining 8-oxoguanine in plasma and urine was developed by high-performance liquid chromatography with electrochemical detection. The compound was separated by gradient elution on a C18 reversed-phase column with a mobile phase of acetonitrile and 0.1 M sodium acetate, pH 5.2. 8-Hydroxy-2′-deoxyguanosine was used as internal standard. 8-Oxoguanine was detected electrochemically by setting the potential to +300 mV vs. Pd reference. The sensitivity of the assay was 22 ng/ml with a signal-to-noise ratio of 7:1. The within-day relative standard deviations for 8-oxoguanine quality control samples with concentrations of 3340, 1340 and 84 ng/ml were 3.6, 4.3 and 5.7% for plasma, and 4.1, 4.6 and 6.2% for urine, respectively. The day-to-day relative standard deviations for the same samples were 3.8, 6.8 and 7.1% for plasma, and 3.9, 7.0 and 7.9% for urine, respectively. The method is designed to study the pharmacokinetics and metabolic fate of O6-benzylguanine in a phase I clinical trial. Previously, O6-benzyl-8-oxoguanine was identified as the primary metabolite of O6-benzylguanine in humans. We now demonstrate that 8-oxoguanine is a further metabolite of O6-benzylguanine.  相似文献   
7.
《Cell》2021,184(23):5728-5739.e16
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The human endolymphatic duct (ED) and sac of the inner ear have been suggested to control endolymph volume and pressure. However, the physiological mechanisms for these processes remain obscure. We investigated the organization of the periductal interstitial connective tissue cells and extracellular matrix (ECM) in four freshly fixed human EDs by transmission electron microscopy and by immunohistochemistry. The unique surgical material allowed a greatly improved structural and epitopic preservation of tissue. Periductal connective tissue cells formed frequent intercellular contacts and focally occurring electron-dense contacts to ECM structures, creating a complex tissue network. The connective tissue cells also formed contacts with the basal lamina of the ED epithelium and the bone matrix, connecting the ED with the surrounding bone of the vestibular aqueduct. The interstitial connective tissue cells were non-endothelial and non-smooth muscle fibroblastoid cells. We suggest that the ED tissue network forms a functional mechanical entity that takes part in the control of inner ear fluid pressure and endolymph resorption.  相似文献   
10.
The discovery that the single p53 gene encodes several different p53 protein isoforms has initiated a flurry of research into the function and regulation of these novel p53 proteins. Full-length p53 protein level is primarily regulated by the E3-ligase Mdm2, which promotes p53 ubiquitination and degradation. Here, we report that all of the novel p53 isoforms are ubiquitinated and degraded to varying degrees in an Mdm2-dependent and -independent manner, and that high-risk human papillomavirus can degrade some but not all of the novel isoforms, demonstrating that full-length p53 and the p53 isoforms are differentially regulated. In addition, we provide the first evidence that Mdm2 promotes the NEDDylation of p53β. Altogether, our data indicates that Mdm2 can distinguish between the p53 isoforms and modify them differently.  相似文献   
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