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41.
Farhan Haq Salmaan Sharif Adnan Khurshid Aamer Ikram Imran Shabbir Muhammad Salman Abdul Ahad Muhammad Suleman Rana Aroosha Raja Nazish Badar Hanaa Tashkandi Turki Al Amri Esam I. Azhar Mohammed S. Almuhayawi Steve Harakeh Muhammad Faraz Arshad Malik 《Saudi Journal of Biological Sciences》2021,28(1):942
42.
Leila Malik Jesper Nygaard Niels J. Christensen Werner W. Streicher Peter W. Thulstrup Lise Arleth Knud J. Jensen 《Journal of peptide science》2013,19(5):283-292
α‐Helical coiled coil structures, which are noncovalently associated heptad repeat peptide sequences, are ubiquitous in nature. Similar amphipathic repeat sequences have also been found in helix‐containing proteins and have played a central role in de novo design of proteins. In addition, they are promising tools for the construction of nanomaterials. Small‐angle X‐ray scattering (SAXS) has emerged as a new biophysical technique for elucidation of protein topology. Here, we describe a systematic study of the self‐assembly of a small ensemble of coiled coil sequences using SAXS and analytical ultracentrifugation (AUC), which was correlated with molecular dynamics simulations. Our results show that even minor sequence changes have an effect on the folding topology and the self‐assembly and that these differences can be observed by a combination of AUC, SAXS, and circular dichroism spectroscopy. A small difference in these methods was observed, as SAXS for one peptide and revealed the presence of a population of longer aggregates, which was not observed by AUC. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
43.
We highlight a case on a normal left testicle with a fibrovascular cord with three nodules consistent with splenic tissue. The torsed splenule demonstrated hemorrhage with neutrophilic infiltrate and thrombus consistent with chronic infarction and torsion. Splenogonadal fusion (SGF) is a rather rare entity, with approximately 184 cases reported in the literature. The most comprehensive review was that of 123 cases completed by Carragher in 1990. Since then, an additional 61 cases have been reported in the scientific literature. We have studied these 61 cases in detail and have included a summary of that information here.Key words: Splenogonadal fusion, Acute scrotumA 10-year-old boy presented with worsening left-sided scrotal pain of 12 hours’ duration. The patient reported similar previous episodes occurring intermittently over the past several months. His past medical history was significant for left hip dysplasia, requiring multiple hip surgeries. On examination, he was found to have an edematous left hemiscrotum with a left testicle that was rigid, tender, and noted to be in a transverse lie. The ultrasound revealed possible polyorchism, with two testicles on the left and one on the right (Figure 1), and left epididymitis. One of the left testicles demonstrated a loss of blood flow consistent with testicular torsion (Figure 2).Open in a separate windowFigure 1Ultrasound of the left hemiscrotum reveals two spherical structures; the one on the left is heterogeneous and hyperdense in comparison to the right.Open in a separate windowFigure 2Doppler ultrasound of left hemiscrotum. No evidence of blood flow to left spherical structure.The patient was taken to the operating room for immediate scrotal exploration. A normalappearing left testicle with a normal epididymis was noted. However, two accessory structures were noted, one of which was torsed 720°; (Figure 3). An inguinal incision was then made and a third accessory structure was noted. All three structures were connected with fibrous tissue, giving a “rosary bead” appearance. The left accessory structures were removed, a left testicular biopsy was taken, and bilateral scrotal orchipexies were performed.Open in a separate windowFigure 3Torsed accessory spleen with splenogonadal fusion.Pathology revealed a normal left testicle with a fibrovascular cord with three nodules consistent with splenic tissue. The torsed splenule demonstrated hemorrhage with neutrophillic infiltrate and thrombus consistent with chronic infarction and torsion (Figure 4).Open in a separate windowFigure 4Splenogonadal fusion, continuous type with three accessory structures. 相似文献
44.
OLAP (On-Line Analytical Processing) is an approach to efficiently evaluate multidimensional data for business intelligence applications. OLAP contributes to business decision-making by identifying, extracting, and analyzing multidimensional data. The fundamental structure of OLAP is a data cube that enables users to interactively explore the distinct data dimensions. Processing depends on the complexity of queries, dimensionality, and growing size of the data cube. As data volumes keep on increasing and the demands by business users also increase, higher processing speed than ever is needed, as faster processing means faster decisions and more profit to industry. In this paper, we are proposing an Adaptive Hybrid OLAP Architecture that takes advantage of heterogeneous systems with GPUs and CPUs and leverages their different memory subsystems characteristics to minimize response time. Thus, our approach (a) exploits both types of hardware rather than using the CPU only as a frontend for GPU; (b) uses two different data formats (multidimensional cube and relational cube) to match the GPU and CPU memory access patterns and diverts queries adaptively to the best resource for solving the problem at hand; (c) exploits data locality of multidimensional OLAP on NUMA multicore systems through intelligent thread placement; and (d) guides its adaptation and choices by an architectural model that captures the memory access patterns and the underlying data characteristics. Results show an increase in performance by roughly four folds over the best known related approach. There is also the important economical factor. The proposed hybrid system costs only 10 % more than same system without GPU. With this small extra cost, the added GPU increases query processing by almost 2 times. 相似文献
45.
Alien invasive species have detrimental effects on invaded communities. Aliens do not invade a vacuum, but rather a community consisting of native and often other alien species. Our current understanding of the pathways and network of interactions among multiple invasive species within whole communities is limited. Eradication efforts often focus on a single target species, potentially leading to unexpected outcomes on interacting non-target species. We aimed to examine the interaction network in a cavity-nesting community consisting of native and invasive birds. We studied the nesting cavities in the largest urban park in Israel over two breeding seasons. We found evidence for a complex interaction network that includes negative, neutral and positive interactions, but no synergistic positive interactions among aliens. Three major factors shaped the interaction network: breeding timing, nesting preferences and the ability to excavate or widen the cavities, which were found to be a limited resource. Cavity enlargement by the early-breeding invasive rose-ringed parakeet may enhance breeding of the invasive common myna in previously unavailable holes. The myna excludes the smaller invasive vinous-breasted starling, a direct competitor of the primary nest excavator, the native Syrian woodpecker. Therefore, management and eradication efforts directed towards the common myna alone may actually release the vinous-breasted starling from competitive exclusion by the common myna, increasing the negative impact of the vinous-breasted starling on the native community. As found here, interactions among multiple alien species can be crucial in shaping invasion success and should be carefully considered when aiming to effectively manage biological invasions. 相似文献
46.
Rift Valley Fever Risk Map Model and Seroprevalence in Selected Wild Ungulates and Camels from Kenya
Seth C. Britch Yatinder S. Binepal Mark G. Ruder Henry M. Kariithi Kenneth J. Linthicum Assaf Anyamba Jennifer L. Small Compton J. Tucker Leonard O. Ateya Abuu A. Oriko Stephen Gacheru William C. Wilson 《PloS one》2013,8(6)
Since the first isolation of Rift Valley fever virus (RVFV) in the 1930s, there have been multiple epizootics and epidemics in animals and humans in sub-Saharan Africa. Prospective climate-based models have recently been developed that flag areas at risk of RVFV transmission in endemic regions based on key environmental indicators that precede Rift Valley fever (RVF) epizootics and epidemics. Although the timing and locations of human case data from the 2006–2007 RVF outbreak in Kenya have been compared to risk zones flagged by the model, seroprevalence of RVF antibodies in wildlife has not yet been analyzed in light of temporal and spatial predictions of RVF activity. Primarily wild ungulate serum samples from periods before, during, and after the 2006–2007 RVF epizootic were analyzed for the presence of RVFV IgM and/or IgG antibody. Results show an increase in RVF seropositivity from samples collected in 2007 (31.8%), compared to antibody prevalence observed from 2000–2006 (3.3%). After the epizootic, average RVF seropositivity diminished to 5% in samples collected from 2008–2009. Overlaying maps of modeled RVF risk assessments with sampling locations indicated positive RVF serology in several species of wild ungulate in or near areas flagged as being at risk for RVF. Our results establish the need to continue and expand sero-surveillance of wildlife species Kenya and elsewhere in the Horn of Africa to further calibrate and improve the RVF risk model, and better understand the dynamics of RVFV transmission. 相似文献
47.
Eun Ju Lee Majid Rasool Kamli Smritee Pokharel Adeel Malik K. M. A. Tareq Abdul Roouf Bhat Hee-Bok Park Yong Seok Lee SangHoon Kim Bohsuk Yang Ki Young Chung Inho Choi 《PloS one》2013,8(11)
Background
Muscle satellite cells (MSCs) represent a devoted stem cell population that is responsible for postnatal muscle growth and skeletal muscle regeneration. An important characteristic of MSCs is that they encompass multi potential mesenchymal stem cell activity and are able to differentiate into myocytes and adipocytes. To achieve a global view of the genes differentially expressed in MSCs, myotube formed-cells (MFCs) and adipocyte-like cells (ALCs), we performed large-scale EST sequencing of normalized cDNA libraries developed from bovine MSCs.Results
A total of 24,192 clones were assembled into 3,333 clusters, 5,517 singletons and 3,842contigs. Functional annotation of these unigenes revealed that a large portion of the differentially expressed genes are involved in cellular and signaling processes. Database for Annotation, Visualization and Integrated Discovery (DAVID) functional analysis of three subsets of highly expressed gene lists (MSC233, MFC258, and ALC248) highlighted some common and unique biological processes among MSC, MFC and ALC. Additionally, genes that may be specific to MSC, MFC and ALC are reported here, and the role of dimethylarginine dimethylaminohydrolase2 (DDAH2) during myogenesis and hemoglobin subunit alpha2 (HBA2) during transdifferentiation in C2C12 were assayed as a case study. DDAH2 was up-regulated during myognesis and knockdown of DDAH2 by siRNA significantly decreased myogenin (MYOG) expression corresponding with the slight change in cell morphology. In contrast, HBA2 was up-regulated during ALC formation and resulted in decreased intracellular lipid accumulation and CD36 mRNA expression upon knockdown assay.Conclusion
In this study, a large number of EST sequences were generated from the MSC, MFC and ALC. Overall, the collection of ESTs generated in this study provides a starting point for the identification of novel genes involved in MFC and ALC formation, which in turn offers a fundamental resource to enable better understanding of the mechanism of muscle differentiation and transdifferentiation. 相似文献48.
Chris Carlsten Assaf P. Oron Heidi Curtiss Sara Jarvis William Daniell Joel D. Kaufman 《PloS one》2013,8(12)
Background
Diesel exhaust (DE) exposures are very common, yet exposure-related symptoms haven’t been rigorously examined.Objective
Describe symptomatic responses to freshly generated and diluted DE and filtered air (FA) in a controlled human exposure setting; assess whether such responses are altered by perception of exposure.Methods
43 subjects participated within three double-blind crossover experiments to order-randomized DE exposure levels (FA and DE calibrated at 100 and/or 200 micrograms/m3 particulate matter of diameter less than 2.5 microns), and completed questionnaires regarding symptoms and dose perception.Results
For a given symptom cluster, the majority of those exposed to moderate concentrations of diesel exhaust do not report such symptoms. The most commonly reported symptom cluster was of the nose (29%). Blinding to exposure is generally effective. Perceived exposure, rather than true exposure, is the dominant modifier of symptom reporting.Conclusion
Controlled human exposure to moderate-dose diesel exhaust is associated with a range of mild symptoms, though the majority of individuals will not experience any given symptom. Blinding to DE exposure is generally effective. Perceived DE exposure, rather than true DE exposure, is the dominant modifier of symptom reporting. 相似文献49.
Joseph E. Knoll William F. Anderson Ravindra Malik Robert K. Hubbard Timothy C. Strickland 《Bioenergy Research》2013,6(3):974-983
Napiergrass (Pennisetum purpureum Schum.) is a high-yielding perennial biomass crop that is well adapted to the Southeast USA where poultry litter is readily available. This research was conducted to compare biomass production and nutrient utilization of napiergrass fertilized with either poultry litter or inorganic fertilizer. Each spring, approximately 100 kg ha?1 of N, 40 kg ha?1 P, and 90 kg ha?1 K were applied as poultry litter or equivalent inorganic fertilizer. Biomass was harvested each winter after senescence. For the first 2 years, dry matter yield did not differ among treatments, but in the third and fourth years, yields declined in all treatments and were lowest in the unfertilized treatment. Biomass N concentration and N removal were greatest in the inorganic treatment. In general, N removal exceeded the amount applied, suggesting that higher application rates may be necessary to maintain yields. Biomass P concentration and total P uptake were greatest in the litter fertilized treatment, demonstrating that napiergrass can remove some of the excess P from applied litter. Soil cores were taken periodically to assess changes in soil properties. After 2 years of production, soil pH in the surface layer (0–15 cm) was lower in the inorganic treatment than in the other treatments. After 4 years, total soil C had increased by an average of 3,180 kg ha?1 though fertilizer treatments did not differ. Yield declined in all treatments after 4 years and N supplementation is recommended for production in upland fields. 相似文献
50.