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91.
The abdominal fat body of the cockroach Blattella germanica contains three characteristic cell types—trophocytes, bacteriocytes and urate cells—which have been investigated by electron microscopy. The trophocytes are rich in lipid droplets of different sizes; glycogen, rough endoplasmic reticulum and mitochondria are also abundant. In females immediately after eclosion, the trophocytes contain a greater number of lipid droplets, some of which have different electron density; glycogen and cytoplasmic organelles are clearly reduced. The bacteriocytes hold rod-like and spherical bacteroids, which are encapsulated by a vacuolar membrane; they show a thin cytoplasmic membrane and an evident cell wall surrounded by a membrane-like outer envelope. The bacteroids appear to be dividing either by transverse partition or by budding. The urate cells, adjacent to the bacteriocytes, are characterized by complex urate vacuoles delimited by a double layer-structure. 相似文献
92.
Giampiero Bartocci Guido Galiazzo Gabriella Ginocchietti Ugo Mazzucato Anna Spalletti 《Photochemical & photobiological sciences》2004,3(9):870-877
Five symmetric (bis-substituted) and asymmetric (mono-substituted) analogues of E-stilbene and EE-1,4-diphenylbutadiene, where one or both the side aryls are 2'-thienyl or 3'-thienyl groups, have been studied by stationary and pulsed fluorimetric techniques, laser flash photolysis, conventional photochemical methods and theoretical calculations. The results obtained for these compounds and the comparison with those previously reported for three other compounds of the same series, allowed the effects of the position of the heteroatom and of the extension of the olefin chain on the excited state relaxation properties to be understood. The presence of one or two thienyl groups and their positional isomerism affect the spectral behaviour, the relaxation properties (radiative/reactive competition), the photoisomerization mechanism (singlet/triplet) and the ground state rotamerism. For the dienes containing the 3'-thienyl substituent(s), two rotamers were evidenced whose radiative and photochemical properties were obtained by selective excitation. 相似文献
93.
Xiaohong R. Yang Melissa Rotunno Yanzi Xiao Christian Ingvar Hildur Helgadottir Lorenza Pastorino Remco van Doorn Hunter Bennett Cole Graham Joshua N. Sampson Michael Malasky Aurelie Vogt Bin Zhu Giovanna Bianchi-Scarra William Bruno Paola Queirolo Giuseppe Fornarini Johan Hansson Rainer Tuominen Laurie Burdett Belynda Hicks Amy Hutchinson Kristine Jones Meredith Yeager Stephen J. Chanock Maria Teresa Landi Veronica Höiom Håkan Olsson Nelleke Gruis Paola Ghiorzo Margaret A. Tucker Alisa M. Goldstein 《Human genetics》2016,135(11):1241-1249
94.
The CDKN2A/p16INK4a 5′UTR sequence and translational regulation: impact of novel variants predisposing to melanoma
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Virginia Andreotti Alessandra Bisio Brigitte Bressac‐de Paillerets Mark Harland Odile Cabaret Julia Newton‐Bishop Lorenza Pastorino William Bruno Roberto Bertorelli Veronica De Sanctis Alessandro Provenzani Chiara Menin Gilberto Fronza Paola Queirolo Robert C. Spitale Giovanna Bianchi‐Scarrà Alberto Inga Paola Ghiorzo 《Pigment cell & melanoma research》2016,29(2):210-221
Many variants of uncertain functional significance in cancer susceptibility genes lie in regulatory regions, and clarifying their association with disease risk poses significant challenges. We studied 17 germline variants (nine of which were novel) in the CDKN2A 5′UTR with independent approaches, which included mono and bicistronic reporter assays, Western blot of endogenous protein, and allelic representation after polysomal profiling to investigate their impact on CDKN2A mRNA translation regulation. Two of the novel variants (c.‐27del23, c.‐93‐91delAGG) were classified as causal mutations (score ≥3), along with the c.‐21C>T, c.‐34G>T, and c.‐56G>T, which had already been studied by a subset of assays. The novel c.‐42T>A as well as the previously described c.‐67G>C were classified as potential mutations (score 1 or 2). The remaining variants (c.‐14C>T, c.‐20A>G, c.‐25C>T+c.‐180G>A, c.‐30G>A, c.‐40C>T, c.‐45G>A, c.‐59C>G, c.‐87T>A, c.‐252A>T) were classified as neutral (score 0). In conclusion, we found evidence that nearly half of the variants found in this region had a negative impact on CDKN2A mRNA translation, supporting the hypothesis that 5′UTR can act as a cellular Internal Ribosome Entry Site (IRES) to modulate p16INK4a translation. 相似文献
95.
Montse Rigat Airy Gras Ugo D’Ambrosio Teresa Garnatje Montse Parada Joan Vallès 《Journal of ethnobiology and ethnomedicine》2016,12(1):49
Background
Wild food plants (WFP) have always been consumed by humans, first as the main basis of their food and, since the origins of agriculture, as ingredients of normal diets or as an alternative during situations of scarcity. In contemporary industrialized societies their use is for the most part being abandoned, but they may still play an important role. With the purpose of advancing in the ethnobotanical knowledge of one region of the Catalan Pyrenees, the present study reports the findings of a research project conducted in the Ripollès district (Catalonia, Iberian Peninsula), concerning ethnobotanical knowledge and use of wild and semi-wild vascular plants as foods, along with minor crops.Methods
From August 2004 to July 2014, we performed 104 interviews (93 of which yielded data on food plants) with 163 informants, using the method of semi-structured ethnobotanical interview. We identified the plants quoted and kept herbarium vouchers.Results
We detected 967 use reports for 80 wild or naturalized taxa, which are or have been consumed in the Ripollès district, the most cited being Taraxacum dissectum, Cynara cardunculus and Origanum vulgare. Certain frequently reported species such as Molopospermum peloponnesiacum and Taraxacum dissectum have only been rarely cited previously or indicated as food plant in very restricted geographical areas. Most cited families included Asteraceae and Lamiaceae, followed by Rosaceae and Apiaceae. Preferred consumed plant parts included leaves, followed by aerial parts, along with fruits and infructescences, while most wild food plants are eaten raw or used as condiments. Demographic factors such as age and locality of informants seem to be more relevant to wild food plant knowledge than gender. Middle-aged people and inhabitants from the Higher Freser River Valley seem to have a greater knowledge of WFP, both in relation to the number of species elicited, as well as the diversity of uses and preparations. To a lesser degree, women seem to have a slightly higher WFP knowledge than men. The consumption of these resources is still fairly alive amongst the populace, yet changes affecting younger generations–in most cases abandonment–have been reported by various participants.Conclusion
The information provided by this kind of research permits the detection of those traditional species that could constitute the basis for the future development and management of wild edible plant resources along with minor crops. It also helps to determine the factors affecting their use, as well as the distinct target groups that such programmes could be addressed to.96.
Gabriella Sozzi Monica Miozzo Silvana Di Palma Antonella Minelli Carla Calderone Cesare Danesino Ugo Pastorino Marco A. Pierotti Giuseppe Della Porta 《Human genetics》1990,85(5):513-515
Summary A cytogenetic analysis of a lung metastasis of an adamantinoma of the tibia, a rare tumor of the long bones, revealed a karyotype 52, XY, t(7;13)(q32;q14), +7, +12, +13, +19, +der(7) t(7;13), +der(13) t(7;13). The t(7;13) was found to be constitutional in the patient and was also present in peripheral blood lymphocytes of his unaffected father. However, both subjects displayed normal levels of esterase D enzyme activity. 相似文献
97.
The mitogen-activated protein kinase (MAPK) signalling pathways play pivotal roles in cellular processes such as proliferation, apoptosis, gene regulation, differentiation, and cell motility. The typical mammalian MAPK pathways ERK1/2, JNK, p38MAPK, and ERK5 operate through a concatenation of three successive phosphorylation events mediated by a MAPK kinase kinase, a MAPK kinase, and a MAPK. MAPKs phosphorylate substrates with distinct functions, including other protein kinases referred to as MAPK-activated protein kinases. One family of related MAPK-activated protein kinases includes MK2, MK3, and MK5. While it is generally accepted that MK2 and MK3 are bona fide substrates for p38MAPK, the genuineness of MK5 as a p38MAPK substrate is disputed. This review summarizes the findings pro and contra an authentic p38MAPK-MK5 relationship, discusses possible explanations for these discrepancies, and proposes experiments that may help to unequivocally clarify whether MK5 is indeed a substrate for p38MAPK. 相似文献
98.
Hexokinase II (HK2), the enzyme that catalyzes the first committed step of glycolysis, is overexpressed in many cancers, as is the central signaling kinase Akt. Akt activity promotes HK2 association with the mitochondria, as well as glucose uptake by cancer cells. In HeLa cervical cancer cells, Akt inhibitor IV (Ai4) increased nuclear HK2 localization, while in MDA‐MB‐231 breast cancer cells, Ai4 merely induced cytoplasmic redistribution without increased nuclear accumulation. Small interfering RNA (siRNA) directed against Akt confirmed the effect in HeLa cells. Next, we treated the cells with clotrimazole (CTZ), which detaches HK2 from the mitochondria, or leptomycin B (LMB), which promotes HK2 nuclear accumulation, and determined the effect on HK2 subcellular distribution. In both cell lines, CTZ detached HK2 from the mitochondria, without substantially increasing nuclear HK2, while LMB increased nuclear HK2, without redistributing cytoplasmic HK2. Contrary to expectations, Akt inhibition promoted glucose uptake in both cell lines, suggesting that Akt inhibition may increase glucose uptake by detaching HK2 from the mitochondria. In both cell lines, CTZ and LMB increased glucose uptake. However, the results in the HeLa cells showed greater effects: CTZ increased glucose uptake to a similar degree to Ai4, while LMB was far more effective than either. These data suggest that both detachment of HK2 from the mitochondria and increased nuclear HK2 are important for Ai4‐induced increased glucose uptake. J. Cell. Physiol. 228: 1943–1948, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
99.
Our knowledge of mammalian iron metabolism has advanced dramatically over recent years. Iron is an essential element for virtually
all living organisms. Its intestinal absorption and accurate cellular regulation is strictly required to ensure the coordinated
synthesis of the numerous iron-containing proteins involved in key metabolic processes, while avoiding the uptake of excess
iron that can lead to organ damage. A range of different proteins exist to ensure this fine control within the various tissues
of the body. Among these proteins, transferrin receptor (TFR2) seems to play a key role in the regulation of iron homeostasis.
Disabling mutations in TFR2 are responsible for type 3 hereditary hemochromatosis (Type 3 HH). This review describes the biological
properties of this membrane receptor, with a particular emphasis paid to the structure, function and cellular localization.
Although much information has been garnered on TFR2, further efforts are needed to elucidate its function in the context of
the iron regulatory network. 相似文献
100.
Bruno Andreoni Antonio Chiappa Emilio Bertani Massimo Bellomi Roberto Orecchia MariaGiulia Zampino Nicola Fazio Marco Venturino Franco Orsi Angelica Sonzogni Ugo Pace Lorenzo Monfardini 《World journal of surgical oncology》2007,5(1):1-10