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91.
The orphan nuclear receptor NR4A1 exhibits pro-oncogenic activity in cancer cell lines. NR4A1 activates mTOR signaling, regulates genes such as thioredoxin domain containing 5 and isocitrate dehydrogenase 1 that maintain low oxidative stress, and coactivates specificity protein 1 (Sp1)-regulated pro-survival and growth promoting genes. Transfection of renal cell carcinoma (RCC) ACHN and 786-O cells with oligonucleotides that target NR4A1 results in a 40–60% decrease in cell proliferation and induction of apoptosis. Moreover, knockdown of NR4A1 in RCC cells decreased bcl-2, survivin and epidermal growth factor receptor expression, inhibited of mTOR signaling, induced oxidative and endoplasmic reticulum stress, and decreased TXNDC5 and IDH1. We have recently demonstrated that selected 1,1-bis(3''-indolyl)-1-(p-substituted phenyl)methane (C-DIM) compounds including the p-hydroxyphenyl (DIM-C-pPhOH) and p-carboxymethyl (DIM-C-pPhCO2Me) analogs bind NR4A1 and act as antagonists. Both DIM-C-pPhOH and DIM-C-pPhCO2Me inhibited growth and induced apoptosis in ACHN and 786-O cells, and the functional and genomic effects of the NR4A1 antagonists were comparable to those observed after NR4A1 knockdown. These results indicate that NR4A1 antagonists target multiple growth promoting and pro-survival pathways in RCC cells and in tumors (xenograft) and represent a novel chemotherapy for treating RCC.  相似文献   
92.
93.
Twenty-one maiden and 29 pluriparous milking Ankara Saanen goats received either two i.m. injections of PGF(2)alpha (n=25) or intravaginal MAP sponges (n=25) early in November at the start of the breeding season. About twice as many pluriparous goats as maiden goats exhibited estrus after either treatment (87% vs. 47%). Breeding after this induced estrus caused pregnancies in 62% of the pluriparous goats, but only in 24% of the maiden animals. Maximal concentrations of progesterone were reached 11 days after the start of the MAP treatment. Progesterone declined to basal levels two to four days after sponge withdrawal. A significant slower progesterone increase also resulting in lower maximal concentrations could be observed in maiden goats. Luteolysis was evident in all animals within 24 h after PGF(2)alpha injection. Nine goats (six maiden and three pluriparous) did not exhibit Heat after the second injection and showed only a slow increase of progesterone. It seems that noncyclic animals are less sensitive to MAP treatment than to the first PGF(2)alpha injection. Goats at the beginning of the breeding season may react after a premature interruption of corpus luteum function (after second PGF(2)alpha injection) with delayed or inadequate follicular function.  相似文献   
94.
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   
95.
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   
96.
Postmating but prezygotic (PMPZ) interactions are increasingly recognized as a potentially important early‐stage barrier in the evolution of reproductive isolation. A recent study described a potential example between populations of the same species: single matings between Drosophila montana populations resulted in differential fertilisation success because of the inability of sperm from one population (Vancouver) to penetrate the eggs of the other population (Colorado). As the natural mating system of D. montana is polyandrous (females remate rapidly), we set up double matings of all possible crosses between the same populations to test whether competitive effects between ejaculates influence this PMPZ isolation. We measured premating isolation in no‐choice tests, female fecundity, fertility and egg‐to‐adult viability after single and double matings as well as second‐male paternity success (P2). Surprisingly, we found no PMPZ reproductive isolation between the two populations under a competitive setting, indicating no difficulty of sperm from Vancouver males to fertilize Colorado eggs after double matings. While there were subtle differences in how P2 changed over time, suggesting that Vancouver males’ sperm are somewhat less competitive in a first‐male role within Colorado females, these effects did not translate into differences in overall P2. Fertilisation success can thus differ dramatically between competitive and noncompetitive conditions, perhaps because the males that mate second produce higher quality ejaculates in response to sperm competition. We suggest that unlike in more divergent species comparisons, where sperm competition typically increases reproductive isolation, ejaculate tailoring can reduce the potential for PMPZ isolation when recently diverged populations interbreed.  相似文献   
97.

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.
  相似文献   
98.
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   
99.
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   
100.
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   
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