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981.
982.
Yousry Hawash Laila Sh. Dorgham Ayman S. Al-Hazmi Mohammed S. Al-Ghamdi 《The Korean journal of parasitology》2014,52(5):479-485
Cryptosporidium diarrhea represents a relevant clinical problem in developing countries. In Al-Taif, a city of Saudi Arabia that lies at an altitude of an around 2 km above the sea level, Cryptosporidium infection seems to be undiagnosed in nearly all clinical laboratories. Furthermore, nothing was published regarding Cryptosporidium-associated diarrhea in this area. The objectives of this research were to (1) determine the Cryptosporidium prevalence among patients with diarrhea and (2) to estimate the performances of 3 different diagnostic methods. Total 180 diarrheal fecal samples, 1 sample per patient, were collected between January and August 2013. Samples were screened for Cryptosporidium with modified Zeihl Neelsen (ZN) microscopy, RIDA® Quick lateral flow (LF) immunotest, and a previously published PCR. The Cryptosporidium prevalence rate was 9.4% (17/180), 10% (18/180), and 11.6% (21/180) by microscopy, LF, and PCR test, respectively. Infection was significantly (P=0.004) predominant among children <5 years (22%) followed by children 5-9 years (11.1%). Although infection was higher in males than in females (16.2% males and 8.5% females), the difference was not statistically significant (P=0.11). Compared to PCR, the sensitivity of microscopy and the LF test were 80.9%, 85.7%, respectively. To conclude, high Cryptosporidium-associated diarrhea was found in this area especially in children ≤9 years. The PCR test showed the best performance followed by the LF test and ZN staining microscopy. The primary health care providers in Al-Taif need to be aware of and do testing for this protozoon, particularly for children seen with diarrhea. 相似文献
983.
984.
Bony fishes of the morphologically diverse infraclass Teleostei include more than 31 000 species, encompassing almost one‐half of all extant vertebrates. A remarkable anatomical complex in teleosts is the adductor mandibulae, the primary muscle in mouth closure and whose subdivisions vary in number and complexity. Difficulties in recognizing homologies amongst adductor mandibulae subdivisions across the Teleostei have hampered the understanding of the evolution of this system and consequently its application in phylogenetic analyses. The adductor mandibulae in representatives of all lower teleost orders is described, illustrated, and compared based on broad taxonomic sampling complemented by extensive literature information. Muscle division homologies are clarified via the application of a standardized homology‐driven anatomical terminology with synonymies provided to the myological terminologies of previous studies. Phylogenetic implications of the observed variations in the adductor mandibulae are discussed and new possible synapomorphies are proposed for the Notacanthiformes, Ostariophysi, Cypriniformes, Siluriphysi, Gymnotiformes, and Alepocephaloidei. New characters corroborate the putative monophyly of the clades Albuliformes plus Notacanthiformes (Elopomorpha), Argentinoidei plus Esocoidei plus Salmonoidei (Protacanthopterygii) and Hemiodontidae plus Parodontidae (Characiformes). We further confirm the validity of characters from the adductor mandibulae previously proposed to support the monophyly of the Esocoidei and the gonorynchiform clade Gonorynchoidei plus Knerioidei. © 2014 The Linnean Society of London 相似文献
985.
Patrick?Al HayekEmail author Blaise?Touzard Yoann?Le Bagousse-Pinguet Richard?Michalet 《Oecologia》2014,174(2):533-543
The effects of species loss on ecosystems depend on the community’s functional diversity (FD). However, how FD responds to environmental changes is poorly understood. This applies particularly to higher trophic levels, which regulate many ecosystem processes and are strongly affected by human-induced environmental changes. We analyzed how functional richness (FRic), evenness (FEve), and divergence (FDiv) of important generalist predators—epigeic spiders—are affected by changes in woody plant species richness, plant phylogenetic diversity, and stand age in highly diverse subtropical forests in China. FEve and FDiv of spiders increased with plant richness and stand age. FRic remained on a constant level despite decreasing spider species richness with increasing plant species richness. Plant phylogenetic diversity had no consistent effect on spider FD. The results contrast with the negative effect of diversity on spider species richness and suggest that functional redundancy among spiders decreased with increasing plant richness through non-random species loss. Moreover, increasing functional dissimilarity within spider assemblages with increasing plant richness indicates that the abundance distribution of predators in functional trait space affects ecological functions independent of predator species richness or the available trait space. While plant diversity is generally hypothesized to positively affect predators, our results only support this hypothesis for FD—and here particularly for trait distributions within the overall functional trait space—and not for patterns in species richness. Understanding the way predator assemblages affect ecosystem functions in such highly diverse, natural ecosystems thus requires explicit consideration of FD and its relationship with species richness. 相似文献
986.
Munef A. Mohammed Dietmar Keyser Mohammed A. Al-Wosabi Bassim Al-Khirbash Wafa M. Al-Qadassi 《Revue de Micropaléontologie》2014
Eleven species belonging to ten genera of fresh water Ostracoda, have been identified from thirteen sediment samples collected from the bottom of permanent streams running along the N-NE part of Socotra Island. The fauna shows close affinity with the S-E African and S-E Asian assemblages, with interesting findings regarding the Palearctic Limnocythere stationis Vávra, 1891. The taxonomy and geographic distribution of the fauna are here discussed in detail. 相似文献
987.
Yusra Al Dhaheri Samir Attoub Gaber Ramadan Kholoud Arafat Khuloud Bajbouj Noushad Karuvantevida Synan AbuQamar Ali Eid Rabah Iratni 《PloS one》2014,9(10)
Background
In this study we investigated the in vitro and in vivo anticancer effect of carnosol, a naturally occurring polyphenol, in triple negative breast cancer.Results
We found that carnosol significantly inhibited the viability and colony growth induced G2 arrest in the triple negative MDA-MB-231. Blockade of the cell cycle was associated with increased p21/WAF1 expression and downregulation of p27. Interestingly, carnosol was found to induce beclin1-independent autophagy and apoptosis in MDA-MB-231 cells. The coexistence of both events, autophagy and apoptosis, was confirmed by electron micrography. Induction of autophagy was found to be an early event, detected within 3 h post-treatment, which subsequently led to apoptosis. Carnosol treatment also caused a dose-dependent increase in the levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (pERK1/2). Moreover, we show that carnosol induced DNA damage, reduced the mitochondrial potential and triggered the activation of the intrinsic and extrinsic apoptotic pathway. Furthermore, we found that carnosol induced a dose-dependent generation of reactive oxygen species (ROS) and inhibition of ROS by tiron, a ROS scavenger, blocked the induction of autophagy and apoptosis and attenuated DNA damage. To our knowledge, this is the first report to identify the induction of autophagy by carnosol.Conclusion
In conclusion our findings provide strong evidence that carnosol may be an alternative therapeutic candidate against the aggressive form of breast cancer and hence deserves more exploration. 相似文献988.
Ermias Diro Lutgarde Lynen Rezika Mohammed Marleen Boelaert Asrat Hailu Johan van Griensven 《PLoS neglected tropical diseases》2014,8(5)
Background
Antimonials are still being used for visceral leishmaniasis (VL) treatment among HIV co-infected patients in East-Africa due to the shortage of alternative safer drugs like liposomal amphotericin B. Besides tolerability, emergence of resistance to antimonials is a major concern.Objectives
This study was aimed at assessing the clinical outcome of VL-HIV co-infected patients when treated with sodium stibogluconate (SSG).Methods
Retrospective patient record analysis of VL-HIV co-infected patients treated at a clinical trial site in north-west Ethiopia was done. Patients with parasitologically confirmed VL and HIV co-infection treated with SSG were included. The dose of SSG used was 20 mg Sb5 (pentavalent antimony)/kg and maximum of 850 mg Sb5 for 30 days. The clinical outcomes were defined based on the tissue aspiration results as cure or failure, and additionally the safety and mortality rates were computed.Results
The study included 57 patients treated with SSG and by the end of treatment only 43.9% of patients were cured. The parasitological treatment failure and the case fatality rate were 31.6% and 14.0% respectively. SSG was discontinued temporarily or permanently for 12 (21.1%) cases due to safety issues. High baseline parasite load (graded more than 4+) was significantly associated with treatment failure (odds ratio = 8.9, 95% confidence interval = .5-51.7).Conclusion
SSG is not only unsafe, but also has low effectiveness for VL-HIV patients. Safe and effective alternative medications are very urgently needed. Drug sensitivity surveillance should be introduced in the region. 相似文献989.
Motivation
Paired-end sequencing protocols, offered by next generation sequencing (NGS) platforms like Illumia, generate a pair of reads for every DNA fragment in a sample. Although this protocol has been utilized for several metagenomics studies, most taxonomic binning approaches classify each of the reads (forming a pair), independently. The present work explores some simple but effective strategies of utilizing pairing-information of Illumina short reads for improving the accuracy of taxonomic binning of metagenomic datasets. The strategies proposed can be used in conjunction with all genres of existing binning methods.Results
Validation results suggest that employment of these “Binpairs” strategies can provide significant improvements in the binning outcome. The quality of the taxonomic assignments thus obtained are often comparable to those that can only be achieved with relatively longer reads obtained using other NGS platforms (such as Roche).Availability
An implementation of the proposed strategies of utilizing pairing information is freely available for academic users at https://metagenomics.atc.tcs.com/binning/binpairs. 相似文献990.
Monoclonal antibody (mAb) products are extraordinarily heterogeneous due to the presence of a variety of enzymatic and chemical modifications, such as deamidation, isomerization, oxidation, glycosylation, glycation, and terminal cyclization. The modifications in different domains of the antibody molecule can result in different biological consequences. Therefore, characterization and routine monitoring of domain-specific modifications are essential to ensure the quality of the therapeutic antibody products. For this purpose, a rapid and informative methodology was developed to examine the heterogeneity of individual domains in mAb products. A recently discovered endopeptidase, IdeS, cleaves heavy chains below the hinge region, producing F(ab')2 and Fc fragments. Following reduction of disulfide bonds, three antibody domains (LC, Fd, and Fc/2) can be released for further characterization. Subsequent analyses by liquid chromatography/mass spectrometry, capillary isoelectric focusing, and glycan mapping enable domain-specific profiling of oxidation, charge heterogeneity, and glycoform distribution. When coupled with reversed phase chromatography, the unique chromatographic profile of each molecule offers a simple strategy for an identity test, which is an important formal test for biopharmaceutical quality control purposes. This methodology is demonstrated for a number of IgGs of different subclasses (IgG1, IgG2, IgG4), as well as an Fc fusion protein. The presented technique provides a convenient platform approach for scientific and formal therapeutic mAb product characterization. It can also be applied in regulated drug substance batch release and stability testing of antibody and Fc fusion protein products, in particular for identity and routine monitoring of domain-specific modifications. 相似文献