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301.
Muhammad Bilal Anwar Rodney Jackson Muhammad Sajid Nadeem Jan E. Jane?ka Shafqat Hussain Mirza Azhar Beg Ghulam Muhammad Mazhar Qayyum 《European Journal of Wildlife Research》2011,57(5):1077-1083
The snow leopard (Panthera uncia) inhabits the high, remote mountains of Pakistan from where very little information is available on prey use of this species. Our study describes the food habits of the snow leopard in the Himalayas and Karakoram mountain ranges in Baltistan, Pakistan. Ninety-five putrid snow leopard scats were collected from four sites in Baltistan. Of these, 49 scats were genetically confirmed to have originated from snow leopards. The consumed prey was identified on the basis of morphological characteristics of hairs recovered from the scats. It was found that most of the biomass consumed (70%) was due to domestic livestock viz. sheep (23%), goat (16%), cattle (10%), yak (7%), and cattle?Cyak hybrids (14%). Only 30% of the biomass was due to wild species, namely Siberian ibex (21%), markhor (7%), and birds (2%). Heavy predation on domestic livestock appeared to be the likely cause of conflict with the local inhabitants. Conservation initiatives should focus on mitigating this conflict by minimizing livestock losses. 相似文献
302.
Premature delivery remains a serious risk factor in pregnancy, with currently licensed tocolytics unable to offer significant improvement in neonatal outcome. Further understanding of the regulators of uterine contractility is required to enable the development of novel and more effective tocolytic therapies. The transglutaminase family is a class of calcium-dependent, transamidating enzymes, of which tissue transglutaminase 2 is a multifunctional enzyme with roles in cell survival, migration, adhesion, and contractility. The aim of the present study was to investigate the role of this enzyme in regulating the contractility of pregnant human myometrium. Tissue strips from biopsy samples obtained at elective cesarean section were either allowed to contract spontaneously or induced to contract with oxytocin, phenylephrine, or bradykinin. Activity integrals, used to measure contractile activity, were taken following cumulative additions of the reversible, polyamine transglutaminase inhibitors cystamine and mono-dansylcadaverine and the irreversible, site-specific transglutaminase inhibitors N-benzyloxycarbonyl-l-phenylalanyl-6-dimethylsulfonium-5-oxo-L-norleucine and 1,3-dimethyl-2[(oxopropyl)thio]imidazolium. The ability of cystamine and mono-dansylcadaverine to affect oxytocin-mediated calcium mobilization within primary cultured myometrial cells was also measured utilizing a calcium indicator. All inhibitors attenuated myometrial contractions in a concentration-dependent manner independent of the method of contraction stimulus. Similarly cultured myometrial cells preincubated with cystamine and mono-dansylcadaverine displayed an altered calcium response to oxytocin stimulation. Our findings demonstrate a potential role for tissue transglutaminase 2 in regulating uterine contractility in pregnant human myometrium that may be associated with the calcium signaling cascade required for contraction. 相似文献
303.
Morita M Ler LW Fabian MR Siddiqui N Mullin M Henderson VC Alain T Fonseca BD Karashchuk G Bennett CF Kabuta T Higashi S Larsson O Topisirovic I Smith RJ Gingras AC Sonenberg N 《Molecular and cellular biology》2012,32(17):3585-3593
The binding of the eukaryotic initiation factor 4E (eIF4E) to the mRNA 5' cap structure is a rate-limiting step in mRNA translation initiation. eIF4E promotes ribosome recruitment to the mRNA. In Drosophila, the eIF4E homologous protein (d4EHP) forms a complex with binding partners to suppress the translation of distinct mRNAs by competing with eIF4E for binding the 5' cap structure. This repression mechanism is essential for the asymmetric distribution of proteins and normal embryonic development in Drosophila. In contrast, the physiological role of the mammalian 4EHP (m4EHP) was not known. In this study, we have identified the Grb10-interacting GYF protein 2 (GIGYF2) and the zinc finger protein 598 (ZNF598) as components of the m4EHP complex. GIGYF2 directly interacts with m4EHP, and this interaction is required for stabilization of both proteins. Disruption of the m4EHP-GIGYF2 complex leads to increased translation and perinatal lethality in mice. We propose a model by which the m4EHP-GIGYF2 complex represses translation of a subset of mRNAs during embryonic development, as was previously reported for d4EHP. 相似文献
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305.
The bactericidal antibody response to three nontypeable Haemophilus influenzae (NTHi) outer membrane proteins (D, P6, and OMP26) was studied in 24 otitis-prone children (aged 7-28?months) after an acute otitis media (AOM) caused by NTHi. The study was carried out to understand the contribution of antigen-specific bactericidal antibody responses in the class of children who are most vulnerable to recurrent otitis media infections. Levels of protein D (P?=?0.005) and P6 (P?=?0.026) but not OMP26 antibodies were higher in bactericidal sera compared with nonbactericidal sera. For five (24%) and 16 (76%) of 21 bactericidal sera tested, removal of anti-protein D and P6 antibody, respectively, resulted in a two- to fourfold drop in bactericidal antibody. Antibodies to OMP26 did not make any contribution to the overall bactericidal activity in any serum samples. Eleven of 21 sera (52%) had bactericidal activity against a heterologous NTHi (86-028 NP) strain but the titers were significantly lower (P?0.05) as compared to the homologous strains. Future studies of protein D, P6, OMP26, and other potential NTHi vaccine antigens should include studies of bactericidal antibody in children who are otitis prone as a possible correlate of protection. 相似文献
306.
Abnizova I Leonard S Skelly T Brown A Jackson D Gourtovaia M Qi G Te Boekhorst R Faruque N Lewis K Cox T 《Journal of bioinformatics and computational biology》2012,10(2):1241005
The new generation of short-read sequencing technologies requires reliable measures of data quality. Such measures are especially important for variant calling. However, in the particular case of SNP calling, a great number of false-positive SNPs may be obtained. One needs to distinguish putative SNPs from sequencing or other errors. We found that not only the probability of sequencing errors (i.e. the quality value) is important to distinguish an FP-SNP but also the conditional probability of "correcting" this error (the "second best call" probability, conditional on that of the first call). Surprisingly, around 80% of mismatches can be "corrected" with this second call. Another way to reduce the rate of FP-SNPs is to retrieve DNA motifs that seem to be prone to sequencing errors, and to attach a corresponding conditional quality value to these motifs. We have developed several measures to distinguish between sequence errors and candidate SNPs, based on a base call's nucleotide context and its mismatch type. In addition, we suggested a simple method to correct the majority of mismatches, based on conditional probability of their "second" best intensity call. We attach a corresponding second call confidence (quality value) of being corrected to each mismatch. 相似文献
307.
Muhammad Nadeem Alain Mollier Christian Morel Alain Vives Lo?c Prud’homme Sylvain Pellerin 《Plant and Soil》2012,357(1-2):13-24
Background and aims
Phosphorus (P) nutrition is very important during early maize seedling growth. Remobilization of endogenous seed P and uptake of exogenous P are therefore of prime importance during this period. Our objectives were to study the effect of the availability of endogenous and exogenous P on i) remobilization of endogenous seed P, ii) the beginning of exogenous P uptake and its intensity, iii) their interaction and effect on seedling development.Methods
Seeds with high and low reserves of endogenous seed P were cultivated at three rates of availability of exogenous P (0, 100, 1,000?μM) over a growth period of 530 cumulated degree days after sowing. Exogenous P was labeled with radioactive P (32P) to distinguish the two fluxes of P in seedlings, one due to remobilization of seed P and the other to uptake of exogenous P.Results
Initially, 86% of endogenous seed P was localized in the scutellum, mainly in the form of phytate, regardless of initial endogenous seed P. At 89 cumulated degree days after sowing (base temperature: 10°C), 98% of seed phytate was hydrolyzed in all treatments. In treatments with available exogenous P, significant uptake of exogenous P started at 71 cumulated degree days after sowing. Efficient uptake of exogenous P depended on its availability, but was independent of phytate hydrolysis and seedling P status. Significant loss of P from germinating seeds due to efflux was observed and was also independent of the availability of exogenous P.Conclusions
Our results show that hydrolysis of seed P was not influenced by the availability of exogenous P, and conversely, that uptake of exogenous P was not influenced by endogenous P in the seed. This suggests that remobilization of endogenous seed P and uptake of exogenous P by seedling roots are controlled independently. 相似文献308.
309.
310.
Siddiqui N Pandeya SN Khan SA Stables J Rana A Alam M Arshad MF Bhat MA 《Bioorganic & medicinal chemistry letters》2007,17(1):255-259
A series of sulphonamide derivatives (1-11) were synthesized in good yield and evaluated for their possible anticonvulsant activity and neurotoxic study. The structures of the synthesized compounds were confirmed on the basis of their spectral data and elemental analysis. Majority of the compounds were active in MES and scPTZ tests. All the compounds were less toxic than the standard drug phenytoin. 相似文献