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Immunity against infection with Listeria monocytogenes is not achieved from innate immune stimulation by contact with killed but requires viable Listeria gaining access to the cytosol of infected cells. It has remained ill‐defined how such immune sensing of live Listeria occurs. Here, we report that efficient cytosolic immune sensing requires access of nucleic acids derived from live Listeria to the cytoplasm of infected cells. We found that Listeria released nucleic acids and that such secreted bacterial RNA/DNA was recognized by the cytosolic sensors RIG‐I, MDA5 and STING thereby triggering interferon β production. Secreted Listeria nucleic acids also caused RIG‐I‐dependent IL‐1β‐production and inflammasome activation. The signalling molecule CARD9 contributed to IL‐1β production in response to secreted nucleic acids. In conclusion, cytosolic recognition of secreted bacterial nucleic acids by RIG‐I provides a mechanistic explanation for efficient induction of immunity by live bacteria.  相似文献   
23.
Programmed cell death (PCD) in the tapetum of Lathyrus undulatus L. was analyzed based on light, fluorescence and electron microscopy to characterize its spatial and temporal occurrence. Development and processes of PCD in secretory tapetal cells of Lathyrus undulatus L. were correlated with the sporogenous cells and pollen grains. At early stages of development the tapetal cells appeared similar to pollen mother cells, structurally. Concurrent with meiosis, tapetum expanded both tangentially and radially as vacuoles increased in size. Tapetal cells most fully developed at young microspore stage. However, tapetum underwent substantial changes in cell organization including nucleus morphology monitored by DAPI. The TUNEL staining confirmed the occurrence of intra-nucleosomal DNA cleavage. In addition to nuclear degeneration which is the first hallmark of PCD other diagnostic features were observed at vacuolated microspore stage intensely; such as chromatin condensation at the periphery of the nucleus, nuclear membrane degeneration, chromatin release to the cytoplasm, vacuole collapse according to tonoplast rupture, shrinkage of the cytoplasm, the increase and enlargement of the endoplasmic reticulum cisternae and disruption of the plasma membrane. After vacuole collapse due to possible release of hydrolytic enzymes the cell components degraded. Tapetal cells completely degenerated at bicellular pollen stage.  相似文献   
24.
From the roots of Aconitum vulparia Rchb., collected in Prüm (Germany), a new norditerpenoid alkaloid, named alexhumboldtine, has been isolated along with the known norditerpenoid alkaloids lappaconitine, anthranoyllycoctonine, lycoctonine, puberaconitine, ajacine, and septentriodine. The structure of alexhumboldtine was established on the basis of 1H, 13C, DEPT, homonuclear 1H COSY, NOESY, HSQC, and HMBC NMR studies. From the aerial parts of the plant another norditerpenoid alkaloid, aconorine, has been isolated.  相似文献   
25.

Background  

In this study, we investigated the effect of hyperbaric oxygen therapy (HBOT) on the morphology of estradiol valerate (EV) induced polycystic ovary (PCO) to find a new treatment modality for improvement of PCO.  相似文献   
26.
The wing shape and size morphology of populations of the medically important phlebotomine sand fly, Phlebotomus papatasi, were examined in two endemic (south of the Atlas Mountains) and nonendemic (north of the Atlas Mountains) foci of cutaneous leishmaniasis by using geometric morphometrics in Morocco. Although it is present in all of Morocco, P. papatasi is the main vector of Leishmania major in only southern part of the Atlas Mountains. There are four major mountain ranges that serve as geographical barriers for species distribution in the study area and at least four gaps were recognized among these barriers. We found statistically significant differences in wing shape morphology between southern and northern populations. Analysis clearly recognized two main groups of populations on both sides of the mountains. The graphical depiction of Principal Component Analysis (PCA) and Canonical Variates Analysis (CVA) confirmed our morphometric study suggesting that the difference in wing morphology between the populations indicates that the population of P. papatasi shows phenotypic plasticity in the study area. According to centroid size analyses, which were used as measures of wing size differences among different sites, the north population of P. papatasi had relatively larger wings than the south population.  相似文献   
27.
Sandhoff disease (SD) is a lysosomal disorder caused by mutations in the HEXB gene. To date, 43 mutations of HEXB have been described, including 3 large deletions. Here, we have characterized 14 unrelated SD patients and developed a Multiplex Ligation-dependent Probe Amplification (MLPA) assay to investigate the presence of large HEXB deletions. Overall, we identified 16 alleles, 9 of which were novel, including 4 sequence variation leading to aminoacid changes [c.626C>T (p.T209I), c.634C>A (p.H212N), c.926G>T (p.C309F), c.1451G>A (p.G484E)] 3 intronic mutations (c.1082+5G>A, c.1242+1G>A, c.1169+5G>A), 1 nonsense mutation c.146C>A (p.S49X) and 1 small in-frame deletion c.1260_1265delAGTTGA (p.V421_E422del). Using the new MLPA assay, 2 previously described deletions were identified. In vitro expression studies showed that proteins bearing aminoacid changes p.T209I and p.G484E presented a very low or absent activity, while proteins bearing the p.H212N and p.C309F changes retained a significant residual activity. The detrimental effect of the 3 novel intronic mutations on the HEXB mRNA processing was demonstrated using a minigene assay. Unprecedentedly, minigene studies revealed the presence of a novel alternative spliced HEXB mRNA variant also present in normal cells. In conclusion, we provided new insights into the molecular basis of SD and validated an MLPA assay for detecting large HEXB deletions.  相似文献   
28.
Neural cell adhesion molecule (N-CAM) mediates homophilic adhesion between cells and heterophilic adhesion between cells and extracellular matrix in a Ca2+-independent manner. N-CAM is widely expressed during development and plays a crucial role in cell division, migration, and differentiation, but its expression is restricted in adults. The distribution of N-CAM immunoreactivity in adult rat tissues was investigated in the present study. N-CAM immunoreactivity was present in the nervous system in the molecular layer of the cerebellum, ependymal cells surrounding the central canal, axons of the white matter, and in Lamina X of the gray matter of the spinal cord. N-CAM immunoreactivity also was found in autonomic nerves. In the digestive system, N-CAM immunoreactivity was found in the stratified squamous epithelium and nerve plexus of the esophagus, glandular cells of the stomach and pylorus, lamina propria, and epithelium of the villi of the duodenum, jejunum, and ileum. N-CAM immunoreactivity was demonstrated in the secretory cells of the adenohypophysis, islets of Langerhans, and acinar cells of the exocrine pancreas. Alveolar cells of the lung were also N-CAM immunoreactive. In the urinary system, N-CAM immunoreactivity was seen in the proximal convoluted tubules of the kidney. In the male reproductive system, N-CAM immunoreactivity was demonstrated in the nerve plexus around the urethral epithelium and in the nerve fibers around the smooth muscle cells of the corpus cavernosum penis. In the visual system, N-CAM immunoreactivity was seen in the epithelial cells of the corpus ciliaris. Cornea and lens epithelium also showed positive immunoreactivity. Our results suggest that cells in many tissues and organs of the adult rat synthesize N-CAM.  相似文献   
29.
Wheat is widely grown in Turkey in the winter season, generally and weeds have been problem in production. Changes in agricultural practices such as increasing mechanization, changing cropping systems and widely use of herbicides and fertilizers has been causing some changes in weed flora in wheat fields from past to present. A contemporary weed survey was done in 2014 in the wheat fields of ?anl?urfa province, which dominate the production of Southeastern region and results were compared with a former survey done in 1967 in the same region. As a result of the comparison, flora has been notably changed; the number of weed species declined from 221 to 71 which means more than threefold diversity loss. In addition, species common over 50% of fields declined dramatically and some foremost species in the past were not recorded contemporary studies whereas some are recorded later. General density of weeds slightly increased in time with a volunteer crop (lentil) in 2014, however, without volunteer crop, the density also declined by about half. Similarly, the density and frequency of dominant species decreased markedly from past to present except some exceptions. The most important reasons for this change are increased use of herbicides and the change of the regional alternation system. It should be noted that biodiversity loss is lower than comparing to the developed world and there is a chance to conserve this through employing sustainable methods. Furthermore, problems related to weed identification were discussed using data from these surveys.  相似文献   
30.
Peroxisome proliferator-activated receptor alpha (PPARalpha) is mainly expressed in liver and involved in lipid metabolism. Oxidation of certain fatty acids in peroxisomes is under PPARalpha control. A wide variety of lipid molecules activate PPARalpha as well as the fibric acid derivative clofibrate. In the present study, we evaluated the differential activation of PPARalpha with several agonist ligands through its expression and DNA binding in both rat (McA-RH7777) and human (HepG2) hepatoma cell lines. In McA-RH7777 cells, clofibrate alone mediated a higher induction of PPARalpha expression than linoleic acid. In contrast, linoleic acid was the most effective ligand in HepG2 cells and treatment with clofibrate plus linoleic acid did not further increase PPARalpha expression. PPRE-binding activity of PPARalpha in ligand-treated cells was also increased in a parallel manner. We suggest that ligand-induced PPARalpha activation might give rise to differential species-dependent responses.  相似文献   
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