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Iron–sulfur clusters are essential cofactors found in all kingdoms of life and play essential roles in fundamental processes, including but not limited to respiration, photosynthesis, and nitrogen fixation. The chemistry of iron–sulfur clusters makes them ideal for sensing various redox environmental signals, while the physics of iron–sulfur clusters and its host proteins have been long overlooked. One such protein, MagR, has been proposed as a putative animal magnetoreceptor. It forms a rod-like complex with cryptochromes (Cry) and possesses intrinsic magnetic moment. However, the magnetism modulation of MagR remains unknown. Here in this study, iron–sulfur cluster binding in MagR has been characterized. Three conserved cysteines of MagR play different roles in iron–sulfur cluster binding. Two forms of iron–sulfur clusters binding have been identified in pigeon MagR and showed different magnetic properties: [3Fe–4S]-MagR appears to be superparamagnetic and has saturation magnetization at 5 K but [2Fe–2S]-MagR is paramagnetic. While at 300 K, [2Fe–2S]-MagR is diamagnetic but [3Fe–4S]-MagR is paramagnetic. Together, the different types of iron–sulfur cluster binding in MagR attribute distinguished magnetic properties, which may provide a fascinating mechanism for animals to modulate the sensitivity in magnetic sensing. [ABSTRACT FROM AUTHOR]

Aims: To detect abnormal eye movements in Parkinson's disease and explore its correlation with clinical characteristics and their value for diagnosis. Methods: We recruited forty-nine Parkinson's disease patients, including 35 early Parkinson's disease patients (Hoehn-Yahr: 1 to 2 stage) and 14 advanced Parkinson's disease patients (Hoehn-Yahr: 3 to 5 stage) and 23 healthy controls. Clinical manifestations in Parkinson's disease patients were recorded. Oculomotor performances including fixation, gaze, saccade in horizontal and vertical direction, and smooth pursuit in horizontal and vertical direction were measured by video-oculography. Results: We found that five oculomotor parameters, namely square wave jerk frequency, latency of downward saccade, latency of upward saccade, accuracy of upward saccade, and gain of horizontal smooth pursuit were significantly different in Parkinson's disease patients and controls. When combining all these five parameters, we got the diagnostic sensitivity of 78.3% and specificity of 95.2%. More deficits in upward saccade than in other directions were associated with disease duration and progression of Parkinson's disease. Conclusion: Our primary study suggests that oculomotor examination might serve as an aid in the clinical assessment of Parkinson's disease patients and differentiating between early Parkinson's disease and normal controls. [ABSTRACT FROM AUTHOR]

Catechol-O-methyltransferase (COMT) is one of the main enzymes in dopamine metabolism and is reported to be associated with susceptibility to Parkinson's disease (PD) and pharmacotherapy. However, researchers mostly focus on the most common polymorphism, rs4680. In this case-control study, we investigated the association of SNPs other than rs4680 with the levodopa (L-dopa) response and other clinical features in Chinese PD patients. Eleven single nucleotide polymorphisms (SNPs) in the COMT gene were genotyped, and clinical data were collected. Patients with the TT genotype of rs165728 or rs174699 had larger daily levodopa equivalent doses (LEDs) than the patients with CC and CT genotypes under the dominant model (p = 0.01421 for rs165728 and p = 0.02302 for rs174699). Under the dominant model, the patients with GG at rs4680 G > A had a lower occurrence of dyskinesia than those with AA and AG (p = 0.0196). Patients with CC at rs4633 had a lower occurrence of dyskinesia than those with TT and TC (p = 0.0429) under the dominant model. The frequencies of the rs174675 T and rs933271 C alleles were higher in PD patients than in the controls (p < 0.05). Our primary results showed the possible association of SNPs other than the most common functional rs4680 in COMT with interindividual variance in the L-dopa daily dose and susceptibility to dyskinesia in Chinese patients, although this was an exploratory study based on a small sample size. Larger and more randomized samples are necessary for further investigation. [ABSTRACT FROM AUTHOR]

Based on a spherically symmetric, self-gravitating viscoelastic Earth model, we derive a complete set of Green's functions for the post-seismic surface strain changes for four independent dislocation sources: strike-slip, dip-slip, and horizontal and vertical tensile point sources. The post-seismic surface strain changes caused by an arbitrary earthquake can be obtained by a combination of the above Green's functions. The post-seismic surface strain changes in the near field agree well with the results calculated by the method in a half-space Earth model (Wang et al. in Comupt Geosci 32:527–541, 2006), which verifies our Green's functions. With an increase in the epicentral distance, the effect of the curvature on both the co- and post-seismic strain changes clearly increases, revealing the importance of our spherical theory for far-field calculations. Next, we use our Green's functions to simulate the post-seismic surface strain changes that were caused by the viscoelastic relaxation of the mantle over the 6-year period after the Tohoku-Oki Mw 9.0 earthquake. Based on continuous Global Positioning System (GPS) observations around Honshu Island of Japan, Northeastern China, South Korea and the Russian Far East, we also deduce the post-seismic strain changes caused by the Tohoku-Oki Mw 9.0 earthquake. Overall, the distributions of the calculated and GPS-derived strain changes agree well each other. Finally, we compare the relative error between the observed and simulated strain changes over the 3.0–4.5-year period after the earthquake in both the near and far field. We find that the relative errors decrease as the epicentral distance increases, which validates our Green's functions for research in the far field. [ABSTRACT FROM AUTHOR]

Exploring the characteristic of the extreme climatic events, especially future projection is considerably important in assessing the impacts of climatic change on hydrology and water resources system. We investigate the future patterns of climate extremes (2001-2099) in the Haihe River Basin (HRB) derived from Coupled General Circulation Model (CGCM) multimodel ensemble projections using the Bayesian Model Average (BMA) approach, under a range of emission scenarios. The extremes are depicted by three extreme temperature indices (i.e., frost days (FD), growing season length (GSL), and T >90th percentile (TN90)) and five extreme precipitation indices (i.e., consecutive dry days (CDD), precipitation ≥10 mm (R10), maximum 5-day precipitation total (R5D), precipitation >95th percentile (R95T), and simple daily intensity index (SDII)). The results indicate frost days display negative trend over the HRB in the 21st century, particularly in the southern basin. Moreover, a greater season length and more frequent warm nights are also projected in the basin. The decreasing CDD, together with the increasing R10, R5D, R95T, and SDII in the 21st century indicate that the extreme precipitation events will increase in their intensity and frequency in the basin. Meanwhile, the changes of all eight extremes climate indices under A2 and A1B scenarios are more pronounced than in B1. The results will be of practical significance in mitigation of the detrimental effects of variations of climatic extremes and improve the regional strategy for water resource and eco-environment management, particularly for the HRB characterized by the severe water shortages and fragile ecological environment. [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is characterized by Amyloid-β (Aβ) deposition in senile plaques in specific areas of the brain and by intraneuronal p-tau accumulation in neurofibrillary tangles. Cumulative evidence supports that oxidative stress is an important factor in the pathogenesis of AD and contributes to Aβ generation. However, there is no effective treatment for AD. Human umbilical cord mesenchymal stem cells (HUMSCs) have potential therapeutic value for the treatment of neurological disease. However, the therapeutic impact of systemic administration of HUMSCs and their mechanism of action in AD have not yet been determined. Here, we found that intravenous infusion of HUMSCs significantly improved spatial learning and alleviated memory decline in an AβPP/PS1 mouse model of AD. HUMSC treatment also increased glutathione (GSH) activity and ratio of GSH to oxidative glutathione as well as superoxide dismutase activity, while decreasing malondialdehyde activity and protein carbonyl level, which suggests that HUMSC infusion alleviated oxidative stress in AβPP/PS1 mice. In addition, HUMSC infusion reduced β-secretase 1 and CTFβ, thus reducing Aβ deposition in mice. HUMSCs may have beneficial effects in the prevention and treatment of AD. [ABSTRACT FROM AUTHOR]

The source rupture process of the M7.0 Lushan earthquake was here evaluated using 40 long-period P waveforms with even azimuth coverage of stations. Results reveal that the rupture process of the Lushan M7.0 event to be simpler than that of the Wenchuan earthquake and also showed significant differences between the two rupture processes. The whole rupture process lasted 36 s and most of the moment was released within the first 13 s. The total released moment is 1.9×10N m with M=6.8. Rupture propagated upwards and bilaterally to both sides from the initial point, resulting in a large slip region of 40 km×30 km, with the maximum slip of 1.8 m, located above the initial point. No surface displacement was estimated around the epicenter, but displacement was observed about 20 km NE and SW directions of the epicenter. Both showed slips of less than 40 cm. The rupture suddenly stopped at 20 km NE of the initial point. This was consistent with the aftershock activity. This phenomenon indicates the existence of significant variation of the medium or tectonic structure, which may prevent the propagation of the rupture and aftershock activity. The earthquake risk of the left segment of Qianshan fault is worthy of attention. [ABSTRACT FROM AUTHOR]

Spatiotemporal changes in climatic extremes in the Yellow River Basin from 1959 to 2008 were investigated on the basis of a suite of 27 climatic indices derived from daily temperature and precipitation data from 75 meteorological stations with the help of the Mann-Kendall test, linear regression method and GIS technique. Furthermore, the changes in the probability distribution of the extreme indices were examined. The results indicate: (1) The whole basin is dominated by significant increase in the frequency of warm days and warm nights, and dominated by significant decrease in the frequency of cold days and cold nights. Although trends in absolute temperature indices show less spatial coherence compared with that in the percentile-based temperature indices, overall increasing trends can be found in Max Tmax (TXx), Min Tmax (TXn), Max Tmin (TNx) and Min Tmin (TNn). (2) Although the spatial patterns and the number of stations with significant changes for threshold and duration temperature indices are also not identical, general positive trends in warm indices (i.e., summer days (SU25), tropical nights (TR20), warm spell duration indicator and growing season length) and negative trends in cold indices (i.e., frost days, ice days and cold spell duration indicator) can be found in the basin. Annual nighttime temperature has increased at a faster rate than that in daytime temperature, leading to obvious decrease in diurnal temperature range. (3) The changes in precipitation indices are much weaker and less spatially coherent compared with these of temperature indices. For all precipitation indices, only few stations are characterized by significantly change in extreme precipitation, and their spatial patterns are always characterized by irregular and insignificant positive and negative changes. However, generally, changes in precipitation extremes present drying trends, although most of the changes are insignificant. (4) Results at seasonal scale show that warming trends occur for all seasons, particularly in winter. Different from that in other three seasons, general positive trends in max 1-day precipitation (Rx1DAY) and max 5-day precipitation (Rx5DAY) are found in winter. Analysis of changes in probability distributions of indices for 1959-1983 and 1984-2008 indicate a remarkable shift toward warmer condition and a less pronounced tendency toward drier condition during the past decades. The results can provide beneficial reference to water resource and eco-environment management strategies in the Yellow River Basin for associated policymakers and stakeholders. [ABSTRACT FROM AUTHOR]

High-resolution three-dimensional V and V/ V images in the Longtan reservoir area were obtained from local earthquake data by using 3,178 events with total 24,153 P-wave and 23,987 S-wave arrivals collected from 23 seismic stations. The tomographic images show that significant V heterogeneities can be seen at layers of different depth in the Longtan reservoir area. Low- V anomalies both beneath and around the main rivers in the reservoir area may be related to the composition of rocks which are mainly deposit carbonate and arenaceous shale, which contributes to water saturation. We deduced that the high porosity rocks beneath the main rivers may be fully saturated with water. The phenomenon that V is relatively high in the area which is 10-20 km away from the rivers indicates that horizontal saturation of water is limited within a small range of area that is about 10-20 km from the main rivers. The characteristic is significant that seismicity in the Longtan reservoir area is coincident with the distribution of the low- V area. V/ V tomographic images show that V/ V ranges from 1.8 to 2.05 in shallow layers above 4 km depth beneath the Longtan reservoir, suggesting the properties of the rocks are limestone and shale. At the depth of 7 km, the distribution of V/ V image varies quite remarkably, especially in the dam area. This demonstrates that the range of influence by the saturation of water in the media below the reservoir surface can reach 4-7 km depth in the dam area. [ABSTRACT FROM AUTHOR]

Moment tensor solution, rupture process and rupture characteristics of the great Wenchuan M8.0 earthquake are studied by using 39 long-period P and SH waveforms with evenly azimuth coverage of stations. Our results reveal that the Wenchuan M8.0 event consisted of 5 sub-events of Mw⩾7.3 occurring succesively in time and space. Rupture started with a Mw7.3 introductory strike-slip faulting in the first 12 s, then within 12-40 s, two sub-events with Mw7.6 and Mw7.4 occurred within 80 km northeast from the initial point with the dominant rupture type of thrust moving. From 40 to 62 s, a Mw7.5 and Mw7.4 right-lateral strike-slip type of sub-events occurred on the two sides of Beichuan, 120 km away northeast from the initial point. The whole rupture process lasted 105 s and unilaterally propagated from the initial point on the WS section of the Yingxiu-Beichuan fault to the NE direction, resulting in a 230-km-long surface rupture zone and the average surface dislocation is up to 4 m. Two asperities are identified and the whole rupture process is formed by WS and NE parts. In the WS part named Dujiangyang-Wenchuan, where the initial point is located, the rupture process showed reverse faulting with the maximum slip of 8.2 m. Around Mianzhu, rupture changed to right-lateral strike slip faulting and formed a Beichuan-Qingchuan large slip area. The rupture area on this part is about 10 km in depth, shallower than on the WS part. The maximum slip is 6.53 m. Consequently, there formed 2 segments with the surface dislocation larger than 6 m. One is the Dujiangyan-Wenchuan segment with the maximum surface displacement of 6.44 m, the other is the Beichuan-Qingchuan segment with the maximum surface displacement of 6.53 m. This segmentation may have its geological and tectonic background. [ABSTRACT FROM AUTHOR]

Expression levels of human papillomavirus type 1 late genes are determined in part by an AU-rich inhibitory sequence in the 3′ untranslated region on the late mRNAs. Fine mapping of the AU rich inhibitory sequence revealed that it mapped to a 57 nucleotide sequence, consisting of an AU-rich region containing two AUUUA motifs and a U-rich region containing three UUUUU motifs. An internal deletion showed that the U-rich region was required for inhibition. Point mutations in the AUUUA- and UUUUU-motifs inactivated the inhibitory sequence. Analysis of the stability of mRNAs containing the AU-rich sequence in sense or anti-sense orientation showed that mRNAs containing the AU-rich sequence in sense orientation had reduced half life. Analysis of RNA-protein interactions revealed that binding to the inhibitory sequence of three poly(U) binding proteins (38, 44 and 46 kDa) correlated with inhibition and that the same proteins bind to the AU-rich mRNA instability element in the 3′ untranslated region on the human c-fos mRNA. We speculate that the human papillomavirus late mRNAs, produced from several hundred copies of the virus genome present in infected cells, compete with the c-fos mRNAs for destabilizing cellular factors and that this may lead to elevated Fos protein levels in human papillomavirus infected cells [ABSTRACT FROM AUTHOR]

Purpose of review: Primary lateral sclerosis is a progressive neurodegenerative process that primarily affects upper motor neuron and presents with progressive stiffness and spasticity in all muscle groups. Given its rarity, diagnosis can be difficult and there has been limited research into what the best treatment is. This review will work to summarize the current available knowledge on the management of primary lateral sclerosis (PLS) including medications, nonpharmacologic interventions, diet, and exercise. Recent findings: There have been no controlled studies of therapies in PLS. Management decisions are based on expert opinion from trials of other motor neuron diseases. The disease, while not curable, is treatable. A treatment plan will involve a mixture of medications, nonpharmacologic interventions, and exercise. The plan should be specific for each individual's disabilities and not a one size fits all plan. Multidisciplinary centers with specialists trained in PLS can help to develop a plan. Research into the best practices and new treatments can have the potential to improve function. Summary: While there is no cure for PLS, there are treatments for PLS. Therapy should involve an individualized care plan involving a mixture of treatment options developed and maintained through a multidisciplinary service and science hub model. [ABSTRACT FROM AUTHOR]