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1.
Kenji Tsuji Shinji KitamuraHirofumi Makino 《Biochemical and biophysical research communications》2014
The kidneys are exposed to hypoxic conditions during development. Hypoxia-inducible factor (HIF), an important mediator of the response to hypoxia, is believed to have an important role in development. However, the relationship between HIF and branching morphogenesis has not been elucidated clearly. 相似文献
2.
The vascular system is critical for developmental growth, tissue homeostasis and repair but also for tumor development. Bone morphogenetic protein (BMP) signaling has recently emerged as a fundamental pathway of the endothelium by regulating cardiovascular and lymphatic development and by being causative for several vascular dysfunctions. Two vascular disorders have been directly linked to impaired BMP signaling: pulmonary arterial hypertension and hereditary hemorrhagic telangiectasia. Endothelial BMP signaling critically depends on the cellular context, which includes among others vascular heterogeneity, exposure to flow, and the intertwining with other signaling cascades (Notch, WNT, Hippo and hypoxia). The purpose of this review is to highlight the most recent findings illustrating the clear need for reconsidering the role of BMPs in vascular biology. 相似文献
3.
《Fungal biology》2020,124(1):44-53
Alternaria blight is one of the most devastating diseases of rapeseed-mustard caused by a necrotrophic fungus Alternaria brassicae. Lack of satisfactory resistance resource in Brassica is still a main obstruction for developing resistance against Alternaria. In this study, we have selected Brassica juncea, Sinapis alba and Camelina sativa to understand and unravel the mechanism of disease resistance against Alternaria. Histopathological studies showed early onset of necrosis in B. juncea (1 dpi) and delayed in S. alba (2 dpi) and C. sativa (3 dpi) respectively. Early and enhanced production of hydrogen peroxide (H2O2) was observed in C. sativa and S. alba (6 hpi) when compared to B. juncea (12 hpi). An increase in catalase activity was observed in both C. sativa (36 % at 6 hpi) and S. alba (15 % at 12 hpi), whereas it significantly decreased in B. juncea at 6 hpi (23 %), 12 hpi (30 %) and 24 hpi (8 %). Gene expression analysis showed induction of PR-3 and PR-12 genes only in C. sativa and S. alba when compared to B. juncea suggesting their vital role for Alternaria resistance. In contrast, SA marker genes were significantly expressed in B. juncea only which provides evidence of hormonal cross talk in B. juncea during Alternaria infection thereby increasing its susceptibility. 相似文献
4.
5.
Changsung Kim 《BMB reports》2015,48(5):256-265
Cardiovascular and neurodegenerative diseases are major health threats in many
developed countries. Recently, target tissues derived from human embryonic stem
(hES) cells and induced pluripotent stem cells (iPSCs), such as cardiomyocytes
(CMs) or neurons, have been actively mobilized for drug screening. Knowledge of
drug toxicity and efficacy obtained using stem cell-derived tissues could
parallel that obtained from human trials. Furthermore, iPSC disease models could
be advantageous in the development of personalized medicine in various parts of
disease sectors. To obtain the maximum benefit from iPSCs in disease modeling,
researchers are now focusing on aging, maturation, and metabolism to
recapitulate the pathological features seen in patients. Compared to pediatric
disease modeling, adult-onset disease modeling with iPSCs requires proper
maturation for full manifestation of pathological features. Herein, the success
of iPSC technology, focusing on patient-specific drug treatment,
maturation-based disease modeling, and alternative approaches to compensate for
the current limitations of patient iPSC modeling, will be further discussed.
[BMB Reports 2015; 48(5): 256-265] 相似文献
6.
Wayne W. Poon Anthony J. Carlos Brittany L. Aguilar Nicole C. Berchtold Crystal K. Kawano Vahe Zograbyan Tim Yaopruke Michael Shelanski Carl W. Cotman 《The Journal of biological chemistry》2013,288(23):16937-16948
We previously found that BDNF-dependent retrograde trafficking is impaired in AD transgenic mouse neurons. Utilizing a novel microfluidic culture chamber, we demonstrate that Aβ oligomers compromise BDNF-mediated retrograde transport by impairing endosomal vesicle velocities, resulting in impaired downstream signaling driven by BDNF/TrkB, including ERK5 activation, and CREB-dependent gene regulation. Our data suggest that a key mechanism mediating the deficit involves ubiquitin C-terminal hydrolase L1 (UCH-L1), a deubiquitinating enzyme that functions to regulate cellular ubiquitin. Aβ-induced deficits in BDNF trafficking and signaling are mimicked by LDN (an inhibitor of UCH-L1) and can be reversed by increasing cellular UCH-L1 levels, demonstrated here using a transducible TAT-UCH-L1 strategy. Finally, our data reveal that UCH-L1 mRNA levels are decreased in the hippocampi of AD brains. Taken together, our data implicate that UCH-L1 is important for regulating neurotrophin receptor sorting to signaling endosomes and supporting retrograde transport. Further, our results support the idea that in AD, Aβ may down-regulate UCH-L1 in the AD brain, which in turn impairs BDNF/TrkB-mediated retrograde signaling, compromising synaptic plasticity and neuronal survival. 相似文献
7.
Understanding of the ecology of infected animals facilitates disease risk assessment and is also crucial for wildlife conservation. Relatively little is known about the spatial distribution of infected wild mammals in relation to environmental factors. In neighboring Mediterranean ecosystems 250 European brown hares (Lepus europaeus) were collected and examined with RT-PCR to detect European Brown Hare Syndrome Virus (EBHSV). Multivariate statistics and Geographical Information System (GIS) analysis were applied to estimate spatial patterns of biotic and abiotic factors and human activities as determinants of EBHSV positivity. Hare population abundance was estimated using faeces counts and belt drive censuses. The study showed that EBHSV infected hares had widespread distribution even in isolated areas. However, EBHSV infection prevalence was higher in areas with higher hare abundance, closer to paved road networks and at lower altitudes. The risk map revealed the potential distribution of EBHSV-infected hares. This study shows that host abundance and landscape influence the ecology of the disease, a finding that should be taken into account in future studies. The management of harvest and restocking of hares is also discussed for population conservation. 相似文献
8.
Dr. J. D. Newstead 《Cell and tissue research》1987,250(2):401-411
Summary The medullary pyramid of renculi in kidneys of ringed seals (Phoca hispida) is enclosed by a basket composed of ribbons of stromal tissue continuous with the wall of the calyx. Branched smooth muscle cells with well-developed Golgi complexes and rough endoplasmic reticulum and only an incomplete external lamina are the principal cells in sites near the origin of the ribbons from the calycal wall. Deeper in the corticomedullary junctional region, smooth muscle is progressively replaced with stellate or spindle-shaped cells exhibiting structural characteristics intermediate between those of fibroblasts and smooth muscle fibers. These myofibroblast-like cells contain arrays of parallel microfilaments 6–8 nm thick with associated focal densities and subplasmalemmal dense plaques, caveolae, elongate, often deeply wrinkled nuclei, and well-developed Golgi complexes and rough endoplasmic reticulum. Material resembling external lamina is associated with parts of the surfaces of most myofibroblast-like cells and intermediate junctions are present. Fibroblasts lacking arrays of parallel microfilaments are a minority at any level in the stromal ribbons. Interstitial cells in the vicinity of the corticomedullary junction show similar myofibroblast-like characteristics. The smooth muscle and myofibroblast-like cells presumably assist expression of urine from the papilla and calyx, and possibly participate as pacemakers for the urinary tract. 相似文献
9.
The purpose of this study was to investigate the distribution of protein-polysaccharides in the glomerular and non-glomerular
regions of the nephron. The techniques used include the digestion of kidney slices with specific polysaccharidases: neuraminidase,
hyaluronidase, chondroitinase ABC, and collagenase followed by several cytochemical techniques to identify the glycosaminoglycans
and glycoproteins at the light and electron microscope levels. Differential staining of hyaluronic acid and sulphated glycosaminoglycans
was accomplished with Alcian Blue at pH 2.5 and pH 0.5, respectively. Sialoproteins were stained with Alcian Blue at pH 2.5.
The periodic acid Schiff’s reaction technique was employed for the visualization of collagen. At the electron microscope level
the polysaccharides were identified with the periodic acid-chromic acid-silver methenamine reaction. Our results indicated
that the major polysaccharide components of the glomerular basement membrane were sialoproteins and collagen, with smaller
amounts of hyaluronic acid and various sulphated glycosaminoglycans. Hyaluronidase digestion resulted in partial detachment
of epithelial processes from the glomerular basement membrane indicating the hyaluronic acid may have a role in the stability
of the attachment of these processes. Tubular basement membranes also contain sialoproteins and sulphated glycosaminoglycans
but in considerably lower concentrations than the glomerular basement membrane. Bowman’s capsule appears to contain mostly
sulphated glycosaminoglycans and has a lower concentration of sialoproteins and hyaluronic acid. 相似文献
10.
The sensitivity of choline transport to inhibition by ethylcholine mustard aziridinium (ECMA) was studied in several tissues. Choline transport was found to be inhibited irreversibly by ECMA in guinea pig and rat synaptosomes but not inhibited in erythrocytes or kidney slices. If this finding can be extended to other tissues ECMA sensitivity may provide a simple criterion for identifying the choline carrier associated with cholinergic tissue. 相似文献