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371.
Histone acetyl transferases are important regulators of cellular homeostasis. This study describes a sensitive acetyl transferase electrophoretic mobility shift assay applicable both for kinetic analysis of acetyl transferase inhibitors and for high-throughput testing. Application of the assay for human GCN5L2 enabled dissection of inhibitor competition with respect to acetyl coenzyme A. Furthermore, we demonstrated that the assay can detect time-dependent inhibition of human GCN5L2 by reactive inhibitors.  相似文献   
372.
373.
Incubation of human serum with cobra or viper venoms (10 micrograms/0.1 ml serum) caused negligible decrease in total protease inhibitory activity whereas alpha 2-macroglobulin activity was reduced by 67.0-82.0% in 16 hr. The action of venoms on MG activity was time dependent. Human alpha 2-macroglobulin activity was reduced to a much greater extent than goat or bovine factors by the venoms. While 25 micrograms venoms/0.1 ml serum caused 60-100% inhibition of human alpha 2-macroglobulin activity, the bovine factor was not affected under similar conditions. Goat alpha 2-macroglobulin was affected to the extent of 0-20%. Evidence is provided to show that venom proteases generate endogenous proteases in situ in human plasma or serum which in turn bind to alpha 2-macroglobulin. The venom-mediated action was abolished by prior dialysis of the serum or its dilution. Ethylenediaminetetraacetate at 10(-3) M concentration also blocked the reaction. While phenylmethylsulfonyl fluoride had no effect, pepstatin in the concentration range 10(-2) to 10(-3) M caused partial inhibition of the venom-mediated inhibition of alpha 2-macroglobulin activity in human serum.  相似文献   
374.
All extant species in the Rhinocerotidae family are experiencing escalating threats in the wild, making self-sustaining captive populations essential genetic reservoirs for species survival. Assisted reproductive technologies (ARTs) will become increasingly important for achieving and maintaining ex situ population sustainability and genetic diversity. Previous reports have shown that a large proportion of captive southern white rhinoceros (SWR) females are irregularly cyclic or acyclic, and that cycling females display two different estrous cycle lengths of approximately 30 or 70 days. It has been suggested that the longer estrous cycle length is infertile or subfertile, as no term pregnancies have been observed following long cycles. Here we report the achievement of two pregnancies following long luteal phases, using ovulation induction and artificial insemination with either fresh or frozen-thawed semen. One female SWR conceived on the first insemination attempt and gave birth to a live offspring. A second female conceived twice in consecutive long cycles although the first embryo was resorbed by 33 days post-insemination. A pregnancy from this female's second insemination is ongoing with expected parturition in November 2019. Whether prolonged estrous cycles in SWR are subfertile or infertile in natural breeding situations remains unclear. However, our findings demonstrate that the application of ARTs following prolonged cycles can result the successful establishment of pregnancies in SWR. Therefore, with ARTs, female SWR otherwise considered nonreproductive due to long estrous cycles may still have the potential for representation and contribution to the ex situ population.  相似文献   
375.
The Sepsidae is, with approximately 300 described species, a relatively small family of cyclorrhaphan flies whose behaviour, morphology, and development have been extensively studied. However, currently the only available tree for Sepsidae is more than 10 years old and was based entirely on morphological characters. Here, we present the results of parsimony and Bayesian analyses based on 75 species, ten genes, and morphology. Parsimony and Bayesian analyses produce largely congruent and well‐supported topologies regardless of whether indels are coded as 5th character states, as missing values, or all sites with indels are removed. The tree confirms the monophyly of Sepsidae and identifies the Ropalomeridae as its sister group. With regard to higher‐level relationships, we identify widespread conflict between the morphological and the DNA sequence data. The proposed hypothesis based on both partitions largely reflects the signal in the molecular data. Particularly surprising is the rejection of two relationship hypotheses with strong morphological support, namely the sister group relationship between Orygma and the remaining Sepsidae and the monophyly of the Sepsis species group. Our partitioned Bremer support (PBS) analyses imply that indel coding has a stronger effect on the relative performance of individual gene partitions than the exclusion of alignment‐ambiguous sequences or the location of a gene on the mitochondrial or nuclear genome. However, these analyses also reveal unexpectedly strong fluctuations in PBS values given that indel treatment has only a minor effect on tree topology and jacknife support. These unexpected fluctuations highlight the need for a comparative study across multiple data sets that investigates the influence of conflict and indel treatment on PBS values. © The Willi Hennig Society 2008.  相似文献   
376.
Murashige and Skoog’s (MS) basal medium with benzylaminopurine (BA), kinetin (KN), zeatin (Z), and thidiazuron (TDZ) were tested for induction of multiple shoots from mature-tree-derived axillary meristems of Pongamia pinnata. Sprouting of buds was 64% on medium devoid of plant growth regulators (PGR). Incorporation of BA, KN, or Z was ineffective in enhancing sprouting frequency or induction of multiple shoots. Sprouting was completely suppressed in the presence of TDZ. Caulogenic buds appeared in nodal meristems of these explants after withdrawal of TDZ. The number of shoot buds was more on explants precultured in higher concentrations. At higher concentrations of this PGR, a swelling developed at the axil. Multiple shoot primordia appeared and differentiated from this swelling after culturing these explants on MS medium for six passages of 2 wk each. Shoots were harvested and cultured on 0.45 μM TDZ for further proliferation. Primary explants after harvesting of shoots were identified as ‘stump’. Reculturing of stumps on 0.45 μM TDZ produced more shoots. This step was followed for six cycles to obtain additional shoots in each cycle. Shoots maintained on 0.45 μM TDZ elongated and rooted (70%) on growth regulator-free medium. Rooted shoots (65%) survived transfer to a sand/soil mixture. This report describes the protocol for micropropagation of P. pinnata using mature-tree-derived nodal meristems. Recycling of mature stock to produce a stream of useable shoots for subculturing and eventual stabilization is of great value and can possibly be generalized as an isolation protocol especially for woody species. Repeated proliferation of caulogenic buds from the same origin may also find application in rescue of endangered germplasm.  相似文献   
377.
Osteoblasts play an important role in bone regeneration and repair. The hypoxia condition in bone occurs when bone undergoes fracture, and this will trigger a series of biochemical and mechanical changes to enable bone repair. Hence, it is interesting to observe the metabolites and metabolism changes when osteoblasts are exposed to hypoxic condition. This study has looked into the response of human osteoblast hFOB 1.19 under normoxic and hypoxic conditions by observing the cell growth and utilization of metabolites via Phenotype MicroArrays™ under these two different oxygen concentrations. The cell growth of hFOB 1.19 under hypoxic condition showed better growth compared to hFOB 1.19 under normal condition. In this study, osteoblast used glycolysis as the main pathway to produce energy as hFOB 1.19 in both hypoxic and normoxic conditions showed cell growth in well containing dextrin, glycogen, maltotriose, D-maltose, D-glucose-6-phospate, D-glucose, D-mannose, D-Turanose, D-fructose-6-phosphate, D-galactose, uridine, adenosine, inosine and α-keto-glutaric acid. In hypoxia, the cells have utilized additional metabolites such as α-D-glucose-1-phosphate and D-fructose, indicating possible activation of glycogen synthesis and glycogenolysis to metabolize α-D-glucose-1-phosphate. Meanwhile, during normoxia, D-L-α-glycerol phosphate was used, and this implies that the osteoblast may use glycerol-3-phosphate shuttle and oxidative phosphorylation to metabolize glycerol-3-phosphate.  相似文献   
378.
Polarimetric imaging and image analysis have gained increased interest in soft tissue analysis at the cellular level. However, polarimetric imaging has widely been tested on thin tissue sections to provide reliable information correlated with histopathological findings. Polarimetric bulk tissue analysis always offered an overall assessment of various tissue optical properties for diagnosis. In this study, the histopathological correlation of bulk tissue polarimetry images for soft tissues is discussed. The first-hand information on the use of bulk tissue Mueller polarimetry and image analysis as an alternative to tissue histopathology is presented for surgically extracted colon and breast tissues.  相似文献   
379.
Serine/threonine protein kinases (STPK) play a major role in the physiology and pathogenesis of Mycobacterium tuberculosis. Here, we have examined the role of pknE, a STPK in the adaptive responses of M. tuberculosis using a deletion mutant ΔpknE. The survival of ΔpknE was assessed in the presence of stress (pH, surfactant and cell wall–damaging agents) and anti-tuberculosis drugs. ΔpknE had a defective growth in pH 7.0 and lysozyme (a cell wall–damaging agent) with better survival in pH 5.5, SDS and kanamycin (a second-line anti-tuberculosis drug). Furthermore, ΔpknE was reduced in cell size during growth in liquid media and exhibited hypervirulence in a guinea pig model of infection. In conclusion, our data suggest that pknE plays a role in adaptive response of M. tuberculosis regulating cellular integrity and survival.  相似文献   
380.
The sillaginid fishes of Visakhapatnam Coast, Bay of Bengal, are found to be hosts for 16 species of digeneans of which seven are adult digeneans belonging to families Opecoelidae, Zoogonidae and Hemiuridae and nine are larval digeneans representing families Bucephalidae, Heterophyidae, Cryptogonimidae, Acanthocolpidae, Hemiuridae and Didymozoidae. The digenean fauna of sillaginid fishes from shallow coastal waters (< 10 m depth) and deeper offshore waters (30–50 m depth) are compared and results are discussed in the light of existing information on the migratory movements of different species of sillaginids and their occurrence in coastal or offshore waters. The usefulness of metacercariae of these fishes as 'biological tags' is considered.  相似文献   
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