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921.
922.
Samuel Wanji Ebanga-Echi Eyong Nicholas Tendongfor Che Ngwa Elive Esuka Arnaud Kengne-Ouafo Fabrice Datchoua-Poutcheu Peter Enyong Adrian Hopkins Charles D. Mackenzie 《PLoS neglected tropical diseases》2015,9(11)
Background
Loiasis, a filarial infection caused by Loa loa usually thought to cause relatively minor morbidity, can cause serious and often fatal reactions in patients carrying very high levels of circulating Loa loa microfilariae (mf) following administration of microfilaricidal drugs. An experimental model of this condition would greatly aid the definition of the optimal management of this important clinical presentation.Methodology/Principle Findings
Fifteen baboons (Papio anubis) were infected with 600 infective larvae (L3) isolated from Chrysops vector flies. Animals were observed for any clinical changes; blood samples were collected every 1–2 months for 22 months, and analysed for parasitological, hematological and biochemical profiles using standard techniques. All animals became patent but remained clinically normal throughout the study. The parasitological pre-patent period was between 4–8 months, with a majority (60%) of animals becoming patent by 5 months post infection (MPI); all animals were patent by 8 MPI. Microfilarial loads increased steadily in all animals and reached a peak at 18 MPI. By 10 MPI >70% of animals had mf >8,000 mf/mL, and at 18 MPI >70% of animals had mf >30,000mf/mL with 50% of these animals with mf >50,000mf/mL. Absolute eosinophil, creatinine, Ca2+ and K+ levels were generally above normal values (NV). Positive associations were seen between microfilariaemia and eosinophilia, Hb, Ca2+, and gamma-GT values, whilst significant negative associations were seen between microfilariaemia and potassium, glucose and mononuclear leukocyte levels.Conclusions
Infection of splenectomised baboons with L. loa can induce levels of circulating microfilariae, and corresponding haematological profiles, which parallel those seen in those humans in danger of the severe post-microfilariacide clinical responses. Utilization of this experimental model could contribute to the improved management of the loiasis related adverse responses in humans. 相似文献923.
Extensive genetic studies have identified a large number of causal genetic variations in many human phenotypes; however, these could not completely explain heritability in complex diseases. Some researchers have proposed that the “missing heritability” may be attributable to gene–gene and gene–environment interactions. Because there are billions of potential interaction combinations, the statistical power of a single study is often ineffective in detecting these interactions. Meta-analysis is a common method of increasing detection power; however, accessing individual data could be difficult. This study presents a simple method that employs aggregated summary values from a “case” group to detect these specific interactions that based on rare disease and independence assumptions. However, these assumptions, particularly the rare disease assumption, may be violated in real situations; therefore, this study further investigated the robustness of our proposed method when it violates the assumptions. In conclusion, we observed that the rare disease assumption is relatively nonessential, whereas the independence assumption is an essential component. Because single nucleotide polymorphisms (SNPs) are often unrelated to environmental factors and SNPs on other chromosomes, researchers should use this method to investigate gene–gene and gene–environment interactions when they are unable to obtain detailed individual patient data. 相似文献
924.
925.
Ainsah Omar Osman Che Bakar Nor Fatini Adam Hakim Osman Arina Osman Ahmad Hatim Suleiman Mohd Rizal Abdul Manaf Mohd Ikhsan Selamat 《The Korean journal of parasitology》2015,53(1):29-34
The aim of this cross sectional case control study was to examine the serofrequency and serointensity of Toxoplasma gondii (Tg) IgG, IgM, and DNA among patients with schizophrenia. A total of 101 patients with schizophrenia and 55 healthy controls from Sungai Buloh Hospital, Selangor, Malaysia and University Malaya Medical Center (UMMC) were included in this study. The diagnosis of schizophrenia was made based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). The presence of Tg infection was examined using both indirect (ELISA) and direct (quantitative real-time PCR) detection methods by measuring Tg IgG and IgM and DNA, respectively. The serofrequency of Tg IgG antibodies (51.5%, 52/101) and DNA (32.67%, 33/101) among patients with schizophrenia was significantly higher than IgG (18.2%, 10/55) and DNA (3.64%, 2/55) of the controls (IgG, P=0.000, OD=4.8, CI=2.2-10.5; DNA, P=0.000, OD=12.9, CI=2.17-10.51). However, the Tg IgM antibody between patients with schizophrenia and controls was not significant (P>0.005). There was no significant difference (P>0.005) in both serointensity of Tg IgG and DNA between patients with schizophrenia and controls. These findings have further demonstrated the strong association between the active Tg infection and schizophrenia. 相似文献
926.
927.
Praveen?D. Chowdary Daphne?L. Che Kai Zhang Bianxiao Cui 《Biophysical journal》2015,108(11):2691-2703
We present a detailed motion analysis of retrograde nerve growth factor (NGF) endosomes in axons to show that mechanical tugs-of-war and intracellular motor regulation are complimentary features of the near-unidirectional endosome directionality. We used quantum dots to fluorescently label NGF and acquired trajectories of retrograde quantum-dot-NGF-endosomes with <20-nm accuracy at 32 Hz in microfluidic neuron cultures. Using a combination of transient motion analysis and Bayesian parsing, we partitioned the trajectories into sustained periods of retrograde (dynein-driven) motion, constrained pauses, and brief anterograde (kinesin-driven) reversals. The data shows many aspects of mechanical tugs-of-war and multiple-motor mechanics in NGF-endosome transport. However, we found that stochastic mechanical models based on in vitro parameters cannot simulate the experimental data, unless the microtubule-binding affinity of kinesins on the endosome is tuned down by 10 times. Specifically, the simulations suggest that the NGF-endosomes are driven on average by 5–6 active dyneins and 1–2 downregulated kinesins. This is also supported by the dynamics of endosomes detaching under load in axons, showcasing the cooperativity of multiple dyneins and the subdued activity of kinesins. We discuss the possible motor coordination mechanism consistent with motor regulation and tugs-of-war for future investigations. 相似文献
928.
This study is designed to evaluate the visual outcomes, accuracy, and predictability of corneal flaps with different thicknesses created by 60-kHz femtosecond laser according to different corneal thicknesses in the patients with low and moderate refractive error. A total of 182 eyes were divided according to the central corneal thickness (470μm–499 μm in Group A, 500μm–549 μm in Group B, and 550μm–599 μm in Group C) and underwent femtosecond laser-assisted LASIK for a target corneal flap thickness (100 μm for Group A, 110 μm for Group B, and 120 μm for Group C). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and refractive status were examined. The flap thickness of each eye was measured by anterior segment optical coherence tomography (AS-OCT) on 30 points at 1-month follow-up to assess the accuracy and predictability. Postoperatively, at least 75% of eyes had a UDVA of 20/16 or better, less than 2% of eyes lost one line, over 30% of eyes gained one or more lines in CDVA, at least 95% of eyes had astigmatism of less than 0.25 D, all eyes achieved a correction within ±1.00 D from the target spherical equivalent refraction. The visual and refractive outcomes did not differ significantly in all groups (P >0.05). The mean flap thickness was 100.36± 4.32 μm (range: 95–113 μm) in Group A, 111.64 ± 3.62 μm (range: 108–125 μm) in Group B, and 122.32 ± 2.88 μm (range: 112–128 μm) in Group C. The difference at each measured point among the three groups was significant (P < 0.05). The accuracy and predictability were satisfactory in all three groups. In conclusion, this customized treatment yielded satisfactory clinical outcomes with accurate and predictable flap thickness for patients with low and moderate refractive error. 相似文献
929.
Shuang Ma Xiaoxue Zhu Jing Zhang Lirong Zhang Rongxiao Che Fang Wang Hanke Liu Haishan Niu Shiping Wang Xiaoyong Cui 《Ecology and evolution》2015,5(18):3995-4005
Organic nitrogen (N) uptake by plants has been recognized as a significant component of terrestrial N cycle. Several studies indicated that plants have the ability to switch their preference between inorganic and organic forms of N in diverse environments; however, research on plant community response in organic nitrogen uptake to warming and grazing is scarce. Here, we demonstrated that organic N uptake by an alpine plant community decreased under warming with 13C–15N‐enriched glycine addition method. After 6 years of treatment, warming decreased plant organic N uptake by 37% as compared to control treatment. Under the condition of grazing, warming reduced plant organic N uptake by 44%. Grazing alone significantly increased organic N absorption by 15%, whereas under warming condition grazing did not affect organic N uptake by the Kobresia humilis community on Tibetan Plateau. Besides, soil NO3–N content explained more than 70% of the variability observed in glycine uptake, and C:N ratio in soil dissolved organic matter remarkably increased under warming treatment. These results suggested warming promoted soil microbial activity and dissolved organic N mineralization. Grazing stimulated organic N uptake by plants, which counteracted the effect of warming. 相似文献
930.
Yanhong Yuan Xiajing Che Zhaohui Ni Yifei Zhong Yinghui Qi Xinghua Shao Qin Wang Liou Cao Minfang Zhang Yuanyuan Xie Chaojun Qi Lei Tian Shan Mou 《PloS one》2015,10(9)