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141.

Background

Idiopathic membranous nephropathy (IMN) is increasingly seen in older patients. However, differences in disease presentation and outcomes between older and younger IMN patients remain controversial. We compared patient characteristics between younger and older IMN patients.

Methods

We recruited 171 Japanese patients with IMN, including 90 (52.6%) patients <65 years old, 40 (23.4%) patients 65–70 years, and 41 (24.0%) patients ≥71 years. Clinical characteristics and outcomes were compared between younger and older IMN patients.

Results

During a median observation period of 37 months, 103 (60.2%) patients achieved complete proteinuria remission, which was not significantly associated with patient age (P = 0.831). However, 13 (7.6%) patients were hospitalized because of infection. Multivariate Cox proportional hazards models identified older age [adjusted hazard ratio (HR) = 3.11, 95% confidence interval (CI): 1.45–7.49, per 10 years; P = 0.003], prednisolone use (adjusted HR = 11.8, 95% CI: 1.59–242.5; P = 0.014), and cyclosporine used in combination with prednisolone (adjusted HR = 10.3, 95% CI: 1.59–204.4; P = 0.012) as significant predictors of infection. A <25% decrease in proteinuria at 1 month after immunosuppressive therapy initiation also predicted infection (adjusted HR = 6.72, 95% CI: 1.51–37.8; P = 0.012).

Conclusions

Younger and older IMN patients had similar renal outcomes. However, older patients were more likely to develop infection when using immunosuppressants. Patients with a poor response in the first month following the initiation of immunosuppressive therapy should be carefully monitored for infection and may require a faster prednisolone taper.  相似文献   
142.
As a part of our continuing research on NPY-Y5 receptor antagonists in the series of novel 6-methoxybenzo[a]cycloheptene derivatives, we discovered a novel skeleton, 7-methoxy-1-hydroxytetraline 7 which had been used as an intermediate, to be more suitable for increasing potencies leading to compound 3 (FR230481). Additionally, we discovered that the naphthalenesulfonamide moiety which was thought to be an essential pharmacophore could be replaced by the 5-chlorobenzothiazolin-3-acetic acid moiety to lead to potent compound 4 (FR233118). The structure-activity relationships on compounds 3,4 and their related derivatives are described. Unfortunately, although compounds 3 and 4 had very high affinities for Y5 receptors, their poor permeabilities to brain were shown by exo-vivo binding assays when orally administered.  相似文献   
143.
Human DICER1 protein cleaves double-stranded RNA into small sizes, a crucial step in production of single-stranded RNAs which are mediating factors of cytoplasmic RNA interference. Here, we clearly demonstrate that human DICER1 protein localizes not only to the cytoplasm but also to the nucleoplasm. We also find that human DICER1 protein associates with the NUP153 protein, one component of the nuclear pore complex. This association is detected predominantly in the cytoplasm but is also clearly distinguishable at the nuclear periphery. Additional characterization of the NUP153-DICER1 association suggests NUP153 plays a crucial role in the nuclear localization of the DICER1 protein.  相似文献   
144.
145.
The germline stem cells (GSCs) are critical for gametogenesis throughout the adult life. Stem cell identity is maintained by local signals from a specialized microenvironment called the niche. However, it is unclear how systemic signals regulate stem cell activity in response to environmental cues. In our previous article, we reported that mating stimulates GSC proliferation in female Drosophila. The mating-induced GSC proliferation is mediated by ovarian ecdysteroids, whose biosynthesis is positively controlled by Sex peptide signaling. Here, we characterized the post-eclosion and post-mating expression pattern of the genes encoding the ecdysteroidogenic enzymes in the ovary. We further investigated the biosynthetic functions of the ovarian ecdysteroid in GSC maintenance in the mated females. We also briefly discuss the regulation of the ecdysteroidogenic enzyme-encoding genes and the subsequent ecdysteroid biosynthesis in the ovary of the adult Drosophila.  相似文献   
146.
147.
The essential oil of German chamomile showed specific inhibition toward aflatoxin G1 (AFG1) production, and ( E )- and ( Z )-spiroethers were isolated as the active compounds from the oil. The ( E )- and ( Z )-spiroethers inhibited AFG1 production of Aspergillus parasiticus with inhibitory concentration 50% (IC50) values of 2.8 and 20.8 μM, respectively, without inhibiting fungal growth. Results of an O- methylsterigmatocystin (OMST) conversion study indicated that the spiroethers specifically inhibited the OMST to AFG1 pathway. A cytochrome P450 monooxygenase, CYPA, is known as an essential enzyme for this pathway. Because CYPA has homology with TRI4, a key enzyme catalyzing early steps in the biosynthesis of trichothecenes, the inhibitory actions of the two spiroethers against TRI4 reactions and 3-acetyldeoxynivalenol (3-ADON) production were tested. ( E ) - and ( Z ) - spiroethers inhibited the enzymatic activity of TRI4 dose-dependently and interfered with 3-ADON production by Fusarium graminearum , with IC50 values of 27.1 and 103 μM, respectively. Our results suggest that the spiroethers inhibited AFG1 and 3-ADON production by inhibiting CYPA and TRI4, respectively.  相似文献   
148.
Genetic variation associated with Picea jezoensis populations of South Korea was investigated using chloroplast (cp), mitochondrial (mt) and nuclear DNA markers. In South Korea, P. jezoensis is distributed across a very restricted area, being found on the summits of three mountains: Mts. Jiri, Dokyu and Gyebang. Examination of five region restriction enzyme combinations for mtDNA and four for cpDNA revealed haplotypes endemic to South Korea. The Gyebang population, the most northerly and most isolated, was genetically distinct from the other populations. Nuclear microsatellite markers indicated, overall, a low level of genetic diversity (H e = 0.406) in South Korea; this could be attributed to genetic drift and/or founder effects associated with historical events. The Wilcoxon sign-rank test did not indicate a recent bottleneck in any of the populations irrespective of the model considered (infinite allele model, two-phased model of mutation, and stepwise mutation model). Microsatellite markers also demonstrated that the Gyebang population was distinct from the others. The results of this study could be used as the basis for conservation guidelines for the management of this species in South Korea.  相似文献   
149.
Osteopontin (OPN) contains at least two major integrin recognition domains, Arg159-Gly-Asp161 (RGD) and Ser162-Val-Val-Tyr-Gly-Leu-Arg168 (SVVYGLR), recognized by αvβ3 and α5β1 and α4 and α9 integrins, respectively. OPN is specifically cleaved by thrombin and matrix metalloproteinase (MMP)-3 or MMP-7 at a position of Arg168/Ser169 (R/S) and Gly166/Leu167 (G/L), respectively. We in this study examined the requirement of residues within SVVYGLR for the α4 and α9 integrin recognition and how MMP-cleavage influences the integrin recognition. The residues, Val164, Tyr165, and Leu167 are critical for α4 and α9 integrin recognition in both cell adhesion and cell migration. The residue Arg168 is additionally required for α9 integrin recognition in cell adhesion and this explains why α9 integrin binds to only thrombin cleaved form of OPN. α4 integrin is able to bind to SVVYG (MMP-cleaved form of RAA OPN-N half), while α9 integrin is not, supporting the above notion that Arg168 is additionally required for α9 integrin-mediated cell adhesion. The residue Val163 is important for α4, but not for α9 integrin recognition in cell migration. Importantly, we found that the replacement of Arg168 by Ala (R168A mutant) induces the augmentation of cell migration via α4 and α9 integrins.  相似文献   
150.
In the course of a study of 6-N-amino-substituted analogues of NB-506 (1), a more potent anticancer drug, J-109,404 (2), in which the formyl group of NB-506 was replaced with a 1,3-dihydroxypropane group, was reported. A study of further modification in the positions of two hydroxyl groups at the indole rings of 2 resulted in the discovery of a 2,10-dihydroxy analogue, J-107,088 (3), which is a promising anticancer agent with a broader therapeutic window than J-109,404.  相似文献   
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