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61.
The interaction of prostaglandin E2 (PGE2) and aspirin with the responses to peri-arterial stimulation (PS) and norepinephrine (NE) was studied in the isolated kidney of rabbit perfused through the renal artery at constant flow with Krebs' solution. NE and PS increased vascular perfusion pressure of kidney and caused a contraction on the isolated rabbit aortic strip superfused with the effluent from kidney. Addition of PGE2 to the perfusion medium decreased the PS-induced rise in perfusion pressure without changing the effect of exogenous NE. In contrast, addition of aspirin to the perfusion medium induced a potentiation of the response to PS but not to NE. These results suggest that PGE2 modulates the effect of PS probably by inhibiting the release of NE from sympathetic nerve endings.  相似文献   
62.
We investigated the effect of α-melanocyte stimulating hormone (α-MSH) on endotoxin-induced intestinal inflammation and the role of nitric oxide and prostaglandins in this response. α-MSH treatment (25 μg/rat, intraperitoneally (i.p.); twice daily) reduced the severity of the lesions macroscopically and microscopically. This protective effect was found to be confined mainly to the distal ileum. These lesions were reversed by pretreatment with the non-selective COX inhibitor indomethacin (10 mg/kg, subcutaneously (s.c.)) but not by the selective COX-2 inhibitor nimesulide (3 mg/kg, s.c.), the NO donor sodium nitroprusside (4 mg/kg, i.v.) or the iNOS inhibitor dexamethasone (3 mg./kg, i.p.) at macroscopic level and reversed by Indo or Dex at microscopic level. Increased peroxidase activity -index of tissue neutrophil infiltration- in the distal ileum of LPS-treated rats was decreased by α-MSH and this effect was reversed by pretreatment with Indo. In conclusion, the neuropeptide α-MSH has a beneficial effect on endotoxin-induced distal intestinal lesions by a mechanism which probably involves nitric oxide and COX-1 derived prostaglandins.  相似文献   
63.
Wound healing requires cells that increase both collagen production as a result of inflammatory events and regeneration of epithelial tissue. The Plantago species of herbs have been used in traditional treatment of skin disorders and infectious diseases, and digestive, respiratory, reproductive and circulatory conditions. We investigated the efficacy of different concentrations of Plantago lanceolata L. extract (PLE) for wound healing owing to its anti-inflammatory, anti-bacterial, anti-fungal, anti-oxidant, anti-ulcerative, analgesic and immunomodulatory properties. We used 72 mice in four groups of 18. An excisional 1 cm wound was created in the skin on the back of the mice in all groups. An ointment containing 10% PLE was applied to the wound in group 1, an ointment containing 20% PLE was applied in group 2 and vaseline was applied in group 3. In group 4, no treatment was applied to the wound. On days 7, 14, and 21 of the experiment, six animals in each group were sacrificed after the wounds were photographed and specimens from the wound sites were examined. On day 14, epithelialization was more prominent in group 2, while vascularization and collagen deposition was more advanced in groups 1 and 2 compared to the other groups. Immunohistochemical examination revealed that TGF-β1 expression was elevated on day 14 in all groups; however, this elevation was more limited in groups 1 and 2 than in groups 3 and 4. Although ANGPT-2 expression increased in groups 1 and 4 on day 14, it decreased significantly in groups 2 and 3. We found that different concentrations of PLE exhibited positive effects on wound healing. Application of 10% PLE ointment may be a useful strategy for wound healing.  相似文献   
64.
Okra is an important vegetable crop that provides a significant portion of vitamins and minerals for populations in several countries. Okra has been cultivated in Turkey for centuries, and was likely introduced by the Arabs from Africa in ancient times. In this study, we aimed to clarify the genetic variation within 35 Turkish okra germplasm, by comparing it against 25 different genotypes from India, Africa, and the United States, using 30 morphological characters and 19 sequence-related amplified polymorphism (SRAP) primer combinations. Fruit, leaf, and stem color were the primary characteristics to distinguish the okra accessions. Those features, among 30 individual phenotypic traits, explained 42 % of phenotypic variation in the first three axes of the principal component analysis (PCA) with leaf shape, flower size, cotyledon length, fruit-surface angularity, cotyledon width, and petal color. Phenotypic observation results showed that while 1051 Togo (10.76), Red Wonder (7.99), TR-05-1 (7.2), 1159 Togo (7.17), and Red Balady (7.15) were found to be more divergent accessions, Cajun Queen (5.06), Perkins Spineless (5.09), Jade (5.18), TR-01-1 (5.2), and DLGG (5.32) were the closest okra accessions. According to phenotypic data, Turkish okra accessions were located adjacent to the Indian, American, and African okra accessions in clusters three and four. However, marker data showed that African okra possessed a more distinct form compared to the other okra germplasms. Nineteen SRAP primer combinations produced 92 bands and 29 (31.5 %) of them were found to be polymorphic among okra accessions. 1051 Togo was found to be the most divergent accession in phenotypic observation.  相似文献   
65.
Natural root-knot nematode resistance genes are unique resources to control this major pest in pepper (Capsicum annuum). Although four genes (Me1, Me3, Me7 and N) conferring broad-spectrum resistance were mapped to a cluster in a 28-cm interval on chromosome P9, limited markers targeting this region were available. In the present study, the Me-gene cluster was structurally annotated for resistance genes to develop markers targeting the N gene. As a result, the Me-gene cluster (4.07 Mb in size) was found to contain three resistance gene hotspots. In addition, a SSR maker tightly linked to the N gene (0.8 cM away) was developed for marker-assisted selection in pepper.  相似文献   
66.
Various molecular and cellular processes are involved in renal fibrosis, such as oxidative stress, inflammation, endothelial cell injury, and apoptosis. Heat shock proteins (HSPs) are implicated in the progression of chronic kidney disease (CKD). Our aim was to evaluate changes in urine and serum HSP levels over time and their relationships with the clinical parameters of CKD in children. In total, 117 children with CKD and 56 healthy children were examined. The CKD group was followed up prospectively for 24 months. Serum and urine HSP27, HSP40, HSP47, HSP60, HSP70, HSP72, and HSP90 levels and serum anti-HSP60 and anti-HSP70 levels were measured by ELISA at baseline, 12 months, and 24 months. The urine levels of all HSPs and the serum levels of HSP40, HSP47, HSP60, HSP70, anti-HSP60, and anti-HSP70 were higher at baseline in the CKD group than in the control group. Over the months, serum HSP47 and HSP60 levels steadily decreased, whereas HSP90 and anti-HSP60 levels steadily increased. Urine HSP levels were elevated in children with CKD; however, with the exception of HSP90, they decreased over time. In conclusion, our study demonstrates that CKD progression is a complicated process that involves HSPs, but they do not predict CKD progression. The protective role of HSPs against CKD may weaken over time, and HSP90 may have a detrimental effect on the disease course.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-021-01239-9.  相似文献   
67.

Background

Tau is a microtubule-binding protein, which is subject to various post-translational modifications (PTMs) including phosphorylation, methylation, acetylation, glycosylation, nitration, sumoylation and truncation. Aberrant PTMs such as hyperphosphorylation result in tau aggregation and the formation of neurofibrillary tangles, which are a hallmark of Alzheimer’s disease (AD). In order to study the importance of PTMs on tau function, antibodies raised against specific modification sites are widely used. However, quality control of these antibodies is lacking and their specificity for particular modifications is often unclear.

Methods

In this study, we first designed an online tool called ‘TauPTM’, which enables the visualization of PTMs and their interactions on human tau. Using TauPTM, we next searched for commercially available antibodies against tau PTMs and characterized their specificity by peptide array, immunoblotting, electrochemiluminescence ELISA and immunofluorescence technologies.

Results

We demonstrate that commercially available antibodies can show a significant lack of specificity, and PTM-specific antibodies in particular often recognize non-modified versions of the protein. In addition, detection may be hindered by other PTMs in close vicinity, complicating the interpretation of results. Finally, we compiled a panel of specific antibodies and show that they are useful to detect PTM-modified endogenous tau in hiPSC-derived neurons and mouse brains.

Conclusion

This study has created a platform to reliably and robustly detect changes in localization and abundance of post-translationally modified tau in health and disease. A web-based version of TauPTM is fully available at http://www.tauptm.org.
  相似文献   
68.
The aim of the present study was to evaluate relationship of self-mutilative behaviour (SMB) with the severity of childhood trauma and adult attention-deficit/hyperactivity disorder (ADHD) symptoms in a sample of inpatients with alcohol use disorder (AUD). Participants included 188 inpatients with AUD. Participants were evaluated with the Self-mutilative Behaviour Questionnaire, the Childhood Trauma Questionnaire (CTQ-28) and the Adult ADD/ADHD DSM-IV Based Diagnostic Screening and Rating Scale (Adult ADHD Scale). Among inpatients with AUD those who have a history of SMB constituted the SMB group (n = 57, 30.3%), and those without a history of SMB constituted the group without SMB (n = 131, 69.7%). Risk of high ADHD risk was 2.5 times higher among those with SMB. Adult ADHD Scale and CTQ-28 scores were also higher in the group with SMB. In the first backward logistic regression model, the severity of ADHD symptoms predicted the presence of SMB, together with the severity of childhood trauma, whereas in the second model, physical neglect and inattentive (IN) dimension of ADHD predicted the presence of SMB. These findings suggest that the higher severity of physical neglect and adult IN dimension of ADHD may be related to SMB among inpatients with AUD.  相似文献   
69.
70.
Some human cancers maintain telomeres using alternative lengthening of telomeres (ALT), a process thought to be due to recombination. In Kluyveromyces lactis mutants lacking telomerase, recombinational telomere elongation (RTE) is induced at short telomeres but is suppressed once telomeres are moderately elongated by RTE. Recent work has shown that certain telomere capping defects can trigger a different type of RTE that results in much more extensive telomere elongation that is reminiscent of human ALT cells. In this study, we generated telomeres composed of either of two types of mutant telomeric repeats, Acc and SnaB, that each alter the binding site for the telomeric protein Rap1. We show here that arrays of both types of mutant repeats present basally on a telomere were defective in negatively regulating telomere length in the presence of telomerase. Similarly, when each type of mutant repeat was spread to all chromosome ends in cells lacking telomerase, they led to the formation of telomeres produced by RTE that were much longer than those seen in cells with only wild-type telomeric repeats. The Acc repeats produced the more severe defect in both types of telomere maintenance, consistent with their more severe Rap1 binding defect. Curiously, although telomerase deletion mutants with telomeres composed of Acc repeats invariably showed extreme telomere elongation, they often also initially showed persistent very short telomeres with few or no Acc repeats. We suggest that these result from futile cycles of recombinational elongation and truncation of the Acc repeats from the telomeres. The presence of extensive 3′ overhangs at mutant telomeres suggests that Rap1 may normally be involved in controlling 5′ end degradation.  相似文献   
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