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111.
Hot dry winds (Sharav in Israel) are notorious for causing controversial symptoms such as depression, discomfort, headaches, irritability and exacerbation of respiratory ailments. Daily urinalysis combined with study of the complaints of two hundred weather-sensitive patients suffering from Sharav have shown that there exist at least three different patterns of reaction: serotonin hypersecretion causing a general "Irritation Syndrome", catecholamine deficiency resulting in the "Exhaustion Syndrome", histamine and creatinine overproduction combined with clinical "Hyperthyroidism - Forme Fruste" and typical thyroid complaints. These syndromes are amenable to appropriate treatment controlled by urinalysis.
Zusammenfassung Trockene heisse Wüstenwinde (Sharav in Israel) rufen eine seltsame Mischung von Symptomen hervor wie Depression, Unwohlsein, Kopfschmerzen, Reizbarkeit und Verschlimmerung respiratorischer Beschwerden. Tägliche Urinuntersuchungen kombiniert mit dem Studium der verschiedenen Beschwerden von 200 Sharav-gefühligen Personen haben gezeigt, dass drei verschiedene Reaktionsformen vorliegen: Serotonin-Ausschüttung, die zu einem allgemeinen Irritationssyndrom führt; Katecholamin-Mangel, der zu einem typischen Erschöpfungssyndrom führt; Histamin- und Kreatinin-Ausschüttung, die mit leichtem Hyperthyreoidismus einhergehen. Letzteres Syndrom bereitet dem Patienten nur an Sharav-Tagen Beschwerden. Die Syndrome sind durch gezielte und Urin-kontrollierte Behandlung heilbar.

Resume Des vents chauds et secs provenant du désert (le Charav en Israël par exemple) sont connus pour provoquer un ensemble de symptômes particuliers tels que dépression nerveuse, indisposition, céphalées, irritabilité et aggravation des troubles respiratoires. L'analyse journalière de l'urine et l'étude des divers symptômes que présentaient 200 personnes sensibles au Charav ont montré la présence de trois formes différentes de réactions: sécrétion accrue de sérotonine qui conduit à un syndrome d'irritabilité générale; une carence en catécholamine qui se traduit par un syndrome typique d'épuisement; une sécrétion d'histamine et de créatinine parallèle à un faible hyperthyréoïdisme. Ce dernier syndrome ne provoque des troubles aux patients que durant les jours où le Charav souffle. Ces trois syndromes sont guérissables par une médication appropriée et dont l'effet est contrôlé par des analyses d'urine.
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Legionella pneumophila utilizes the Icm/Dot type‐IV secretion system to translocate approximately 300 effector proteins into host cells, and the CpxRA two‐component system (TCS) was previously shown to regulate the expression of several of these effectors. In this study, we expanded the pool of L. pneumophila CpxR‐regulated genes to 38, including 27 effector‐encoding genes. Our study demonstrates for the first time that the CpxR dual regulator has different requirements for activation and repression of target genes. These differences include the positioning of the CpxR regulatory element relative to the promoter element, and the effect of CpxR phosphate donors on the expression of CpxR target genes. In addition, unlike most response regulators, a mutant form of the L. pneumophila CpxR which cannot be phosphorylated was found to self‐interact, and to repress gene expression similarly to wild‐type CpxR, even though its ability to activate gene expression was reduced. Moreover, the CpxRA TCS was found to activate the expression of LetE which was found to function as a connector protein between the CpxRA TCS and the LetAS‐RsmYZ‐CsrA regulatory cascade. Our results show that CpxR plays a major role in L. pneumophila pathogenesis gene expression and functions as part of a regulatory network.  相似文献   
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The R7 family of RGS proteins (RGS6, -7, -9, -11) is characterized by the presence of three domains: DEP, GGL, and RGS. The RGS domain interacts with Galpha subunits and exhibits GAP activity. The GGL domain permanently associates with Gbeta5. The DEP domain interacts with the membrane anchoring protein, R7BP. Here we provide evidence for a novel interaction within this complex: between the DEP domain and Gbeta5. GST fusion of the RGS7 DEP domain (GST-R7DEP) binds to both native and recombinant Gbeta5-RGS7, recombinant Gbetagamma complexes, and monomeric Gbeta5 and Gbeta1 subunits. Co-immunoprecipitation and FRET assays supported the GST pull-down experiments. GST-R7DEP reduced FRET between CFP-Gbeta5 and YFP-RGS7, indicating that the DEP-Gbeta5 interaction is dynamic. In transfected cells, R7BP had no effect on the Gbeta5/RGS7 pull down by GST-R7DEP. The DEP domain of RGS9 did not bind to Gbeta5. Substitution of RGS7 Glu-73 and Asp-74 for the corresponding Ser and Gly residues (ED/SG mutation) of RGS9 diminished the DEP-Gbeta5 interaction. In the absence of R7BP both the wild-type RGS7 and the ED/SG mutant attenuated muscarinic M3 receptor-mediated Ca2+ mobilization. In the presence of R7BP, wild-type RGS7 lost this inhibitory activity, whereas the ED/SG mutant remained active. Taken together, our results are consistent with the following model. The Gbeta5-RGS7 molecule can exist in two conformations: "closed" and "open", when the DEP domain and Gbeta5 subunit either do or do not interact. The closed conformation appears to be less active with respect to its effect on Gq-mediated signaling than the open conformation.  相似文献   
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Necroptosis is a regulated and inflammatory form of cell death. We, and others, have previously reported that necroptotic cells release extracellular vesicles (EVs). We have found that necroptotic EVs are loaded with proteins, including the phosphorylated form of the key necroptosis-executing factor, mixed lineage kinase domain-like kinase (MLKL). However, neither the exact protein composition, nor the impact, of necroptotic EVs have been delineated. To characterize their content, EVs from necroptotic and untreated U937 cells were isolated and analyzed by mass spectrometry-based proteomics. A total of 3337 proteins were identified, sharing a high degree of similarity with exosome proteome databases, and clearly distinguishing necroptotic and control EVs. A total of 352 proteins were significantly upregulated in the necroptotic EVs. Among these were MLKL and caspase-8, as validated by immunoblot. Components of the ESCRTIII machinery and inflammatory signaling were also upregulated in the necroptotic EVs, as well as currently unreported components of vesicle formation and transport, and necroptotic signaling pathways. Moreover, we found that necroptotic EVs can be phagocytosed by macrophages to modulate cytokine and chemokine secretion. Finally, we uncovered that necroptotic EVs contain tumor neoantigens, and are enriched with components of antigen processing and presentation. In summary, our study reveals a new layer of regulation during the early stage of necroptosis, mediated by the secretion of specific EVs that influences the microenvironment and may instigate innate and adaptive immune responses. This study sheds light on new potential players in necroptotic signaling and its related EVs, and uncovers the functional tasks accomplished by the cargo of these necroptotic EVs.Subject terms: Necroptosis, Cell death and immune response  相似文献   
117.
The difference in maximal jump height between static block jump starting from an upright position (upright BJ) and static block jump starting from a squat position (squat BJ) was determined in 10 division II collegiate women volleyball players. Also determined was the difference in take off time for quick block jump, to a constant point above the net, between upright BJs and squat BJs. An AMTI force plate and a video camera (60 Hz) were used to collect the data. Each subject performed three maximal upright BJs and three maximal squat BJs, and five quick upright BJs and five quick squat BJs, randomly. The highest jump for maximal upright BJs and squat BJs, and the fastest jump for quick upright BJs and squat BJs were recorded. There was a significant difference (p < 0.03) between maximal upright BJs and squat BJs in height jump; maximal upright BJ (33.2 cm) was higher by 1.2 cm. No significant difference (p > 0.5) was found for the fastest take off time (approximately 0.7 s) between quick upright BJs and squat BJs. These results suggest that college women volleyball players can jump higher from the upright, compared with the squat, position. They can take off to the same block position equally quickly from either the upright or squat starting position. These data may suggest that conditioning coaches should identify their players' preferred BJ position and incorporate a specific training program to enhance the players' power. Furthermore, the coaches may need to incorporate more specific squat endurance exercises.  相似文献   
118.
Low and high affinity receptors mediate cellular uptake of heparanase   总被引:1,自引:0,他引:1  
Heparanase is an endoglycosidase which cleaves heparan sulfate and hence participates in degradation and remodeling of the extracellular matrix. Importantly, heparanase activity correlated with the metastatic potential of tumor-derived cells, attributed to enhanced cell dissemination as a consequence of heparan sulfate cleavage and remodeling of the extracellular matrix barrier. Heparanase has been characterized as a glycoprotein, yet glycan biochemical analysis was not performed to date. Here, we applied the Qproteometrade mark GlycoArray kit to perform glycan analysis of heparanase, and compared the kit results with the more commonly used biochemical analyses. We employed fibroblasts isolated from patients with I-cell disease (mucolipidosis II), fibroblasts deficient of low density lipoprotein receptor-related protein and fibroblasts lacking mannose 6-phosphate receptor, to explore the role of mannose 6-phosphate in heparanase uptake. Iodinated heparanase has been utilized to calculate binding affinity. We provide evidence for hierarchy of binding to cellular receptors as a function of heparanase concentration. We report the existence of a high affinity, low abundant (i.e., low density lipoprotein receptor-related protein, mannose 6-phosphate receptor), as well as a low affinity, high abundant (i.e., heparan sulfate proteoglycan) receptors that mediate heparanase binding, and suggest that these receptors co-operate to establish high affinity binding sites for heparanase, thus maintaining extracellular retention of the enzyme tightly regulated.  相似文献   
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Foraging traits of seed predators are expected to impact the spatial structure of plant populations, community dynamics and diversity. Yet, many of the key mechanisms governing distance- or density-dependent seed predation are poorly understood. We designed an extensive set of field experiments to test how seed predation by two harvester ant species interact with seed dispersal in shaping the spatial patterns of surviving seeds. We show that the Janzen–Connell establishment pattern can be generated by central-place foragers even if their focal point is located away from the seed source. Furthermore, we found that differences in the social behaviour of seed predators influence their sensitivity to seed density gradients and yield opposing spatial patterns of surviving seeds. Our results support the predictions of a recent theoretical framework that unifies apparently opposing plant establishment patterns, and suggest that differences in foraging traits among seed predators can drive divergent pathways of plant community dynamics.  相似文献   
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