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111.
112.
In juvenile Biomphalaria glabrata snails exposed to irradiated Echinostoma lindoense miracidia, the sporocysts migrated to the heart at the same speed as did nonirradiated sporocysts in control snails. However, in each snail so exposed to irradiated miracidia, amebocyte clumps in the snail's heart destroyed the sporocysts within 2–9 days post-exposure. This process induced a strong, highly specific resistance to homologous reinfection in these previously susceptible snails. The snails remained susceptible to Schistosoma mansoni and Paryphostomum segregatum (Echinostomatidae), but were partially resistant to Echinostoma paraensei and E. liei, two echinostome species closely related to E. lindoense. 相似文献
113.
Breinlia booliati exhibited nocturnal subperiodicity in its natural host, Rattus sabanus in contrast to experimentally infected laboratory-reared albine rats which showed irregular fluctuations of microfilariae throughout the 24 hour cycle. All the infected albino rats showed a prepatent period between 11-14 weeks postinoculation. Three patterns of microfilaraemia were discerned during the course of infection 38/49 rats displayed a single peak, 4/49 displayed 2 peaks about 12-15 weeks apart and 7/49 showed a sustained high plateau-like pattern of microfilaraemia. Cortisone had no effect on microfilarial levels when administered to rats near postpatency and some at postpatency. 相似文献
114.
Jung Mi Lim Kyung S. Lee Hyun Ae Woo Dongmin Kang Sue Goo Rhee 《The Journal of cell biology》2015,210(1):935-945
Proteins associated with the centrosome play key roles in mitotic progression in mammalian cells. The activity of Cdk1-opposing phosphatases at the centrosome must be inhibited during early mitosis to prevent premature dephosphorylation of Cdh1—an activator of the ubiquitin ligase anaphase-promoting complex/cyclosome—and the consequent premature degradation of mitotic activators. In this paper, we show that reversible oxidative inactivation of centrosome-bound protein phosphatases such as Cdc14B by H2O2 is likely responsible for this inhibition. The intracellular concentration of H2O2 increases as the cell cycle progresses. Whereas the centrosome is shielded from H2O2 through its association with the H2O2-eliminating enzyme peroxiredoxin I (PrxI) during interphase, the centrosome-associated PrxI is selectively inactivated through phosphorylation by Cdk1 during early mitosis, thereby exposing the centrosome to H2O2 and facilitating inactivation of centrosome-bound phosphatases. Dephosphorylation of PrxI by okadaic acid–sensitive phosphatases during late mitosis again shields the centrosome from H2O2 and thereby allows the reactivation of Cdk1-opposing phosphatases at the organelle. 相似文献
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116.
A molecular phylogeny of New World emballonurid bats based on parsimony and Bayesian analyses of loci from the three different
nuclear genetic transmission pathways in mammals (autosomal, X, and Y chromosomes) is well supported and independently corroborated by each individual gene tree. This is in contrast to a single
most parsimonious but poorly supported tree based on morphological data, which has only one intergeneric or higher relationship
shared with the molecular phylogeny. Combining the morphological and molecular data partitions results in a tree similar to
the molecular tree suggesting a high degree of homoplasy and low phylogenetic signal in the morphological data set. Behavioral
data are largely incomplete and likewise produce a poorly resolved tree. Nonetheless, patterns of evolution in morphology
and behavior can be investigated by using the molecular tree as a phylogenetic framework. Character optimization of the appearance
of dorsal fur and preferred roosting sites maps consistently and are correlated on the phylogeny. This suggests an association
of camouflage for bats with unusual appearance (two dorsal stripes in Rhynchonycteris and Saccopteryx, or pale fur in Cyttarops and Diclidurus) and roosting in exposed sites (tree trunks or under palm leaves). In contrast, the ancestral states for Old and New World
emballonurids are typically uniform brown or black, and they usually roost in sheltered roosts such as caves and tree hollows.
Emballonuridae is the only family of bats that has a sac-like structure in the wing propatagium, which is found in four New
World genera. Mapping the wing sac character states onto the phylogeny indicates that wing sacs evolved independently within
each genus and that there may be a phylogenetic predisposition for this structure. Ear orientation maps relatively consistently
on the molecular phylogeny and is correlated to echolocation call parameters and foraging behavior, suggesting a phylogenetic
basis for these character systems. 相似文献
117.
Magnesium levels in serum, erythrocytes, skeletal muscle, and bone were measured in 10 patients with valvular heart disease who had received diuretic therapy for heart failure for an average of 3·3 years. Five patients were found to have diminished values for skeletal muscle, indicating significant magnesium deficit. Values for erythrocytes were low in only two of the five patients, and none had low values for serum ultrafiltrate and bone: Magnesium replacement therapy restored skeletal muscle values to normal. Clinical features consistent with the presence of magnesium deficiency were found in all five magnesium-deficient patients. These features were, with few exceptions, corrected by magnesium replacement. The latter also corrected low skeletal muscle potassium values present in all five patients with low skeletal muscle magnesium, four of whom showed clinical features of digoxin poisoning before magnesium therapy was given. Concomitant secondary aldosteronism, inadequate dietary intake, and digoxin therapy had probably augmented the magnesium loss due to diuretic therapy. 相似文献
118.
Protein arginine methyltransferase 5 (PRMT5) is a major enzyme responsible for generating monomethyl and symmetric dimethyl arginine in proteins. PRMT5 is essential for cell viability and development, and its overexpression is observed in a variety of cancers. In the present study, it is found that levels of PRMT5 protein and symmetric arginine dimethylation in colorectal cancer (CRC) tissues are increased compared to those in adjacent noncancerous tissues. Using immunoaffinity enrichment of methylated peptides combined with high‐resolution mass spectrometry, a total of 147 symmetric dimethyl‐arginine (SDMA) sites in 94 proteins are identified, many of which are RNA binding proteins and enzymes. Quantitative analysis comparing CRC and normal tissues reveals significant increase in the symmetric dimethylation of 70 arginine sites in 46 proteins and a decrease in that of four arginine sites in four proteins. Among the 94 proteins identified in this study, it is confirmed that KH‐type splicing regulatory protein is a target of PRMT5 and highly expressed in CRC tissues compared to noncancerous tissues. This study is the first comprehensive analysis of symmetric arginine dimethylation using clinical samples and extends the number of known in vivo SDMA sites. The data obtained are available via ProteomeXchange with the identifier PXD015653. 相似文献
119.
120.
Rahman Daiyan Emma Catherine Lovell Bosi Huang Muhammad Zubair Joshua Leverett Qingran Zhang Sean Lim Jonathan Horlyck Jianbo Tang Xunyu Lu Kourosh Kalantar‐Zadeh Judy N. Hart Nicholas M. Bedford Rose Amal 《Liver Transplantation》2020,10(28)
In this study, scalable, flame spray synthesis is utilized to develop defective ZnO nanomaterials for the concurrent generation of H2 and CO during electrochemical CO2 reduction reactions (CO2RR). The designed ZnO achieves an H2/CO ratio of ≈1 with a large current density (j) of 40 mA cm?2 during long‐term continuous reaction at a cell voltage of 2.6 V. Through in situ atomic pair distribution function analysis, the remarkable stability of these ZnO structures is explored, addressing the knowledge gap in understanding the dynamics of oxide catalysts during CO2RR. Through optimization of synthesis conditions, ZnO facets are modulated which are shown to affect reaction selectivity, in agreement with theoretical calculations. These findings and insights on synthetic manipulation of active sites in defective metal‐oxides can be used as guidelines to develop active catalysts for syngas production for renewable power‐to‐X to generate a range of fuels and chemicals. 相似文献