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911.
There are multiple neurological complications of cancer and its treatment. This study assessed the utility of the novel non-invasive ophthalmic technique of corneal confocal microscopy in identifying neuropathy in patients with upper gastrointestinal cancer before and after platinum based chemotherapy. In this study, 21 subjects with upper gastrointestinal (oesophageal or gastric) cancer and 21 healthy control subjects underwent assessment of neuropathy using the neuropathy disability score, quantitative sensory testing for vibration perception threshold, warm and cold sensation thresholds, cold and heat induced pain thresholds, nerve conduction studies and corneal confocal microscopy. Patients with gastro-oesophageal cancer had higher heat induced pain (P = 0.04) and warm sensation (P = 0.03) thresholds with a significantly reduced sural sensory (P<0.01) and peroneal motor (P<0.01) nerve conduction velocity, corneal nerve fibre density (CNFD), nerve branch density (CNBD) and nerve fibre length (CNFL) (P<0.0001). Furthermore, CNFD correlated significantly with the time from presentation with symptoms to commencing chemotherapy (r = -0.54, P = 0.02), and CNFL (r = -0.8, P<0.0001) and CNBD (r = 0.63, P = 0.003) were related to the severity of lymph node involvement. After the 3rd cycle of chemotherapy, there was no change in any measure of neuropathy, except for a significant increase in CNFL (P = 0.003). Corneal confocal microscopy detects a small fibre neuropathy in this cohort of patients with upper gastrointestinal cancer, which was related to disease severity. Furthermore, the increase in CNFL after the chemotherapy may indicate nerve regeneration.  相似文献   
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Much progress has been made in brain-machine interfaces (BMI) using decoders such as Kalman filters and finding their parameters with closed-loop decoder adaptation (CLDA). However, current decoders do not model the spikes directly, and hence may limit the processing time-scale of BMI control and adaptation. Moreover, while specialized CLDA techniques for intention estimation and assisted training exist, a unified and systematic CLDA framework that generalizes across different setups is lacking. Here we develop a novel closed-loop BMI training architecture that allows for processing, control, and adaptation using spike events, enables robust control and extends to various tasks. Moreover, we develop a unified control-theoretic CLDA framework within which intention estimation, assisted training, and adaptation are performed. The architecture incorporates an infinite-horizon optimal feedback-control (OFC) model of the brain’s behavior in closed-loop BMI control, and a point process model of spikes. The OFC model infers the user’s motor intention during CLDA—a process termed intention estimation. OFC is also used to design an autonomous and dynamic assisted training technique. The point process model allows for neural processing, control and decoder adaptation with every spike event and at a faster time-scale than current decoders; it also enables dynamic spike-event-based parameter adaptation unlike current CLDA methods that use batch-based adaptation on much slower adaptation time-scales. We conducted closed-loop experiments in a non-human primate over tens of days to dissociate the effects of these novel CLDA components. The OFC intention estimation improved BMI performance compared with current intention estimation techniques. OFC assisted training allowed the subject to consistently achieve proficient control. Spike-event-based adaptation resulted in faster and more consistent performance convergence compared with batch-based methods, and was robust to parameter initialization. Finally, the architecture extended control to tasks beyond those used for CLDA training. These results have significant implications towards the development of clinically-viable neuroprosthetics.  相似文献   
915.
Titanium (Ti) is a beneficial element that promotes growth and biomass production although the mechanism by which this improvement takes place is still unclear, as are other effects on plants, although it is believed that Ti can compensate for N deficiency. To prove this hypothesis, a hydroponic experiment was designed to investigate the effect of adding Ti to a nutrient solution on the nutrient uptake of tomato (Lycopersicon esculentum L.) by withholding N within the nutrient solution (NS) by 25?% (NS2) and by 50?% (NS1). Ti was added at 1 and 2?mg?L?1. When Ti was added to nutrient solution, the elemental concentration in tomato changed significantly: K, Ca, Fe, and Zn decreased while Ti increased. As the concentration of N in nutrient solution decreased, the Ca and Ti concentration of tomato leaves decreased and the K, Mn, Fe, Cu, and Zn concentration increased. As the N concentration in nutrient solution increased, the Ca concentration decreased although the application of Ti compensated for Ca concentration in NS1. All the photosynthetic attributes and physiological characteristics, including flower induction, decreased when the N concentration of NS decreased by 50?%, although this decrease could be compensated by applying 1?mg?L?1 Ti. This has valuable and practical applications and implications for tomato hydroponic culture.  相似文献   
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917.
Stallion sperm exhibits great male-to-male variability in survival after cryopreservation. In this study, we have investigated if differences in sperm freezability can be attributed to membrane phase and permeability properties. Fourier transform infrared spectroscopy (FTIR) was used to determine supra and subzero membrane phase transitions and characteristic subzero membrane hydraulic permeability parameters. Sperm was obtained from stallions that show differences in sperm viability after cryopreservation. Stallion sperm undergoes a broad and gradual phase transition at suprazero temperatures, from 30-10°C, whereas freezing-induced dehydration of the cells causes a more severe phase transition to a highly ordered gel phase. Sperm from individual stallions showed significant differences in post-thaw progressive motility, percentages of sperm with abnormal cell morphology, and chromatin stability. The biophysical membrane properties evaluated in this study, however, did not show clear differences amongst stallions with differences in sperm freezability. Cyclodextrin treatment to remove cholesterol from the cellular membranes increased the cooperativity of the suprazero phase transition, but had little effects on the subzero membrane phase behavior. In contrast, freezing of sperm in the presence of protective agents decreased the rate of membrane dehydration and increased the total extent of dehydration. Cryoprotective agents such as glycerol decrease the amount of energy needed to transport water across cellular membranes during freezing.  相似文献   
918.
Although the highest incidence of esophageal squamous cell carcinoma (ESCC) has repeatedly been reported from Persia (Iran), nevertheless the so far proteomic published reports were limited to one study on tissue specimens. Here we report the proteome of a newly established cell line from Persian ESCC patients and compare it with the normal primary cell proteome. Among polypeptides, whose expression was different in cell line sixteen polypeptides were identified by MALDI/TOF/TOF spectrometry. S100-A8 protein, annexin A1, annexin A2, regulatory subunit of calpain, subunit alpha type-3 of proteasome and glutamate dehydrogenase 1 were proteins down-regulated in cell line while peroxiredoxin-5, non-muscle myosin light polypeptide 6, keratin 1, annexin A4, keratin 8, tropomyosin 3, stress-induced-phosphoprotein 1 and albumin were found to be subject of up-regulation in cell line compared to the primary normal cells. The proteomic results were further verified by western blotting and RT-PCR on annexin A1 and keratin 8. In addition, among the aforementioned proteins, glutamate dehydrogenase 1, regulatory subunit of calpain, subunit alpha of type-3 proteasome and annexin A4 are proteins whose deregulation in ESCC is reported for the first time by this study.  相似文献   
919.

Introduction

Different variants of haplotype frequencies may lead to various frequencies of the same variants in individuals with drug resistance and disease susceptibility at the population level.

Materials and methods

In this study, the haplotype frequencies of 4 STR loci including the D8S1132, D8S1779, D8S514 and D8S1743, and 3 STR loci including D11S1304, D11S1998 and D11S934 were investigated in 563 individuals of four Iranian ethnic groups in the capital city of Iran, Tehran. One hundred thirty subjects had the metabolic syndrome. Haplotype frequencies of all markers were calculated.

Results

There were significant differences in the haplotype frequencies in short and long alleles between the metabolic affected subjects and controls. In addition, haplotype frequencies were significant in the four ethnic groups in both chromosomes 8 and 11.

Conclusion

Our findings show a relation between the short allele of D8S1743 in all related haplotype frequencies of subjects with metabolic syndrome. These findings may require more studies of some candidate genes, including the lipoprotein lipase gene, in this chromosomal region.  相似文献   
920.
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