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141.
142.

Purpose

To evaluate the postoperative changes in blebs and levels of aqueous monocyte chemotactic protein-1 (MCP-1) after trabeculectomy vs. Ex-PRESS tube shunt surgery.

Methods

Rabbits were subjected to trabeculectomy or Ex-PRESS tube shunt surgery and observed for up to 3 months. Intraocular pressure (IOP) was measured using a rebound tonometer. The MCP-1 level was measured by enzyme-linked immunosorbent assay (ELISA). Bleb morphology was evaluated using photos and anterior-segment optical coherence tomography (OCT).

Results

There were no differences in bleb appearance or IOP at any time between the groups. Bleb wall density in the anterior-segment OCT image was significantly lower 1 week after surgery in the Ex-PRESS group than the trabeculectomy group. The MCP-1 level in control eyes was 304.1 ± 45.2 pg/mL. In the trabeculectomy group, the mean aqueous MCP-1 level was 1444.9, 1914.3, 1899.8, 516.4, 398.3, 427.3, 609.5, 1612.7, 386.2, and 167.9 pg/mL at 3, 6, and 12 h, and 1, 2, 5, 7, 14, 30, and 90 days after surgery, respectively. In the Ex-PRESS group, the corresponding values were 1744.0, 1372.0, 932.5, 711.7, 396.1, 487.3, 799.5, 1327.9, 293.6, and 184.0 pg/mL. There were no significant differences in the aqueous MCP-1 level between the groups at any time point.

Conclusion

The postoperative changes were similar in the Ex-PRESS and trabeculectomy groups, except for bleb wall density in the anterior-segment OCT image. The postoperative aqueous MCP-1 level had bimodal peaks in both groups.  相似文献   
143.
144.
Loquat canker disease, caused by Pseudomonas syringae pv. eriobotryae, is one of the most harmful diseases of commercial cultivars of loquat (Eriobotrya japonica). To introgress resistance to loquat canker, we identified the linkage group and position of the resistance locus derived from the related wild species bronze loquat (Eriobotrya deflexa). The segregation of resistance and susceptibility fit the expected ratio of 1:1 in 96 individuals from a three-way cross involving bronze loquat (heterozygous for resistance) and two cultivars of loquat (susceptible). The genomic region containing Pse-a was identified by using a genome scanning approach, and the loquat canker resistance locus was mapped at the top of linkage group 10 by applying novel simple sequence repeat (SSR) markers designed on the basis of the ‘Golden Delicious’ apple genome sequence. The constructed linkage group spans 69.4 cM and has an average marker density of 2.6 cM per marker. The developed molecular markers tightly linked to the loquat canker resistance locus will be useful for marker-assisted selection and for introgression of resistance into loquat in breeding programs.  相似文献   
145.
Methylglyoxal (MG), a physiological &#102 -dicarbonyl compound is derived from glycolytic intermediates and produced during the Maillard reaction. The Maillard reaction, a non-enzymatic reaction of ketones and aldehydes with amino group of proteins, contributes to the aging of proteins and to complications associated with diabetes. In our previous studies (Che, et al. (1997) "Selective induction of heparin-binding epidermal growth factor-like growth factor by MG and 3-deoxyglucosone in rat aortic smooth muscle cells. The involvement of reactive oxygen species formation and a possible implication for atherogenesis in diabetes". J. Biol. Chem., 272 , 18453-18459), we reported that MG elevates intracellular peroxide levels, but the mechanisms for this remain unclear. Here, we report that MG inactivates bovine glutathione peroxidase (GPx), a major antioxidant enzyme, in a dose- and time-dependent manner. The use of BIAM labeling, it was showed that the selenocysteine residue in the active site was intact when GPx was incubated with MG. MALDI-TOF-MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) and protein sequencing examined the possibility that MG modifies arginine residues in GPx. The results show that Arg 184 and Arg 185, located in the glutathione binding site of GPx was irreversively modified by treatment with MG. Reactive dicarbonyl compounds such as 3-deoxyglucosone, glyoxal and phenylglyoxal also inactivated GPx, although the rates for this inactivation varied widely. These data suggest that dicarbonyl compounds are able to directly inactivate GPx, resulting in an increase in intracellular peroxides which are responsible for oxidative cellular damage.  相似文献   
146.
147.
Researchers have argued that the process of human birth is unique among primates and mammals in that the infant emerges with its face oriented in the opposite direction from its mother (occiput anterior) and head rotation occurs in the birth canal. However, this notion of human uniqueness has not been substantiated, because there are few comparative studies of birth in non-human primates. This paper reports the mechanism of birth in chimpanzees (Pan troglodytes) based on the first clear, close-up video recordings of three chimpanzee births in captivity. In all three cases, the foetus emerged with an occiput anterior orientation, and the head and body rotated after the head had emerged. Therefore, these characteristics are not uniquely human. Furthermore, in two of the three cases, the chimpanzee newborns landed on the ground without being guided from the birth canal by the mother. The fact that the human newborn emerges with an occiput anterior orientation has thus far been taken as evidence for the necessity of midwifery in modern humans, but this view also needs revision. Our observations raise the need to reconsider the evolutionary scenario of human birth.  相似文献   
148.

Aims

In recent years, there has been an increase in patients with arteriosclerosis and the risk of lifestyle-related diseases. However, the pathogenesis and medication of atherosclerosis have not been elucidated. We developed a rat model of lifestyle-related diseases by feeding a high-fat diet and 30% sucrose solution (HFDS) to spontaneously hypertensive hyperlipidemic rats (SHHR) and reported that this model is a useful model of early atherosclerosis. In order to elucidate the pathogenesis of early atherosclerosis, we searched for atherosclerosis-related genes by microarray analysis using the aortic arch rat model of lifestyle-related diseases.

Main methods

Four-month-old male Sprague–Dawley rats and SHHR were each divided into two normal diet (ND) groups and two HFDS groups. After a four-month treatment, the expression of mRNA in the aortic arch was detected using the oligo DNA microarray one-color method and quantified using real-time PCR.

Key findings

In this study, we detected 39 genes in microarray analysis. Esm1, Retnlb Mkks, and Grem2 showed particularly marked changes in gene expression in the SHHR-HFDS group. Compared with the SD-ND group, the SHHR-HFDS group had an increase in Mkks gene expression of about 26-fold and an approximately 22-fold increase in the expression of Grem2. Similarly, the expression of Esm1 increased by about 12-fold and that of Retnlg by about 10-fold as shown by quantitative real-time PCR.

Significance

This study suggested that these four genes might be important in early atherosclerosis development.  相似文献   
149.
150.
The maize orange leafhopper Cicadulina bipunctata (Hemiptera: Cicadellidae) induces galls characterized by growth stunting and severe swelling of leaf veins on various plants of Poaceae. Previous studies revealed that galls are induced not on feeding site but on distant, newly extended leaves during the feeding, and strongly suggested that some chemicals injected by the leafhopper affect at the leaf primordia. To approach the mechanism underlying gall induction by C. bipunctata, we examined physiological response of plants to feeding by the leafhopper. We performed high-throughput and comprehensive plant hormone analyses using LC-ESI-MS/MS. Galled maize leaves contained higher contents of abscisic acid (ABA) and trans-Zeatin (tZ) and lower contents of gibberellins (GA1 and GA4) than ungalled maize leaves. Leafhopper treatment significantly increased ABA and tZ contents and decreased GA1 and GA4 contents in extending leaves. After the removal of leafhoppers, contents of tZ and gibberellins in extending leaves soon became similar to the control values. ABA content was gradually decreased after the removal of leafhoppers. Such hormonal changes were not observed in leafhopper treatment on leaves of resistant maize variety. Water contents of galled leaves were significantly lower than control leaves, suggesting water stress of galled leaves and possible reason of the increase in ABA content. These results imply that ABA, tZ, and gibberellins are related to gall induction by the leafhopper on susceptible variety of maize.  相似文献   
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