11,180 research outputs found
Population-scale organization of cerebellar granule neuron signaling during a visuomotor behavior.
Granule cells at the input layer of the cerebellum comprise over half the neurons in the human brain and are thought to be critical for learning. However, little is known about granule neuron signaling at the population scale during behavior. We used calcium imaging in awake zebrafish during optokinetic behavior to record transgenically identified granule neurons throughout a cerebellar population. A significant fraction of the population was responsive at any given time. In contrast to core precerebellar populations, granule neuron responses were relatively heterogeneous, with variation in the degree of rectification and the balance of positive versus negative changes in activity. Functional correlations were strongest for nearby cells, with weak spatial gradients in the degree of rectification and the average sign of response. These data open a new window upon cerebellar function and suggest granule layer signals represent elementary building blocks under-represented in core sensorimotor pathways, thereby enabling the construction of novel patterns of activity for learning
The effects of benfotiamine in attenuating hyperglycemia-induced cardiac pathology
Type 2 diabetes is a major global health problem. It is also a risk factor for the onset of cardiovascular diseases, the current leading cause of global mortality. The first part of this mini-review describes hyperglycemia-induced cellular alterations and its effects on cardiac function. In particular, we emphasize the role of hyperglycemia-induced oxidative stress in the activation of non-oxidative glucose pathways (NOGPs), that may contribute to cardiac pathology. For the second part, we evaluate the utility of benfotiamine (a vitamin B1 derivative) in treating diabetes-related cardiac pathology. The focus is on its role in activating the pentose phosphate pathway, which may reduce flux though the NOGPs. A possible role for benfotiamine in activating pro-survival signaling and reducing cell death in the heart is also described. We also discuss benfotiamine’s potential cardioprotective role in preventing the diabetic cardiomyopathy, treating myocardial infarction and maintaining the viability of cardiac progenitor cells. These findings warrant further investigation into the therapeutic potential of benfotiamine in treating diabetes-related cardiac complications.Keywords: Diabetes; cardiovascular disease; hyperglycemia; oxidative stress; non-oxidative glucose pathways; benfotiamin
A case report of lameness in two dairy goat herds: a suspected combination of nutritional factors concurrent with treponeme infection
Background: Two dairy goat farms with high level of lameness in lactating animals were presented for further
investigation. Farm 1 and Farm 2 presented with 37 and 67 % morbidity, respectively. Both farms had an all year round
indoor system, feeding ad libitum concentrate with forage available at all times.
Case presentation: The lameness was found to be based in the foot. Previous treatments consisting of biweekly
footbathing with zinc sulphate, spraying lesions with oxytetracycline spray and packing lesions with copper crystals
on a single occasion and single injections with long acting oxytetracycline had not been successful. Mild cases had
signs of haemorrhaging in the white line or on the sole of the foot. Moderate cases showed under running of the wall
horn or small areas of exposed sole corium. Severe cases would consist of horn or wall separation with the corium
exposed and infected. In extreme cases only the wall horn of the claw remained, with a large area of necrotic tissue
in the centre and no healthy corium visible. Only one animal was seen to have interdigital lesions. Polymerase chain
reaction (PCR) and culture of swabs taken from exposed corium and the interdigital space were negative for Dichelobacter nodosus but PCR for treponemes were positive in both the adults and the youngstock tested. Due to the high
level of concentrate in the diet of these goats, nutrition was thought to contribute to the problem. Transcutaneous
rumen fluid samples were taken and pH was measured on both farms, with 35 % of the samples below pH value 5.5.
Conclusion: No definite diagnosis could be made. However, the results suggest both treponemes and nutrition play
a role in the aetiology of the lameness. The initial sole or wall horn lesions were thought to be secondarily infected
by treponemes. Further investigation is needed to definitively diagnose the cause and contributing factors for this
lamenes
Effect of Al addition on the microstructure and electronic structure of HfO₂film
Author name used in this publication: P. F. LeeAuthor name used in this publication: J. Y. Dai2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Boron neutron capture therapy induces apoptosis of glioma cells through Bcl-2/Bax
<p>Abstract</p> <p>Background</p> <p>Boron neutron capture therapy (BNCT) is an alternative treatment modality for patients with glioma. The aim of this study was to determine whether induction of apoptosis contributes to the main therapeutic efficacy of BNCT and to compare the relative biological effect (RBE) of BNCT, γ-ray and reactor neutron irradiation.</p> <p>Methods</p> <p>The neutron beam was obtained from the Xi'an Pulsed Reactor (XAPR) and γ-rays were obtained from [<sup>60</sup>Co] γ source of the Fourth Military Medical University (FMMU) in China. Human glioma cells (the U87, U251, and SHG44 cell lines) were irradiated by neutron beams at the XAPR or [<sup>60</sup>Co] γ-rays at the FMMU with different protocols: Group A included control nonirradiated cells; Group B included cells treated with 4 Gy of [<sup>60</sup>Co] γ-rays; Group C included cells treated with 8 Gy of [<sup>60</sup>Co] γ-rays; Group D included cells treated with 4 Gy BPA (p-borono-phenylalanine)-BNCT; Group E included cells treated with 8 Gy BPA-BNCT; Group F included cells irradiated in the reactor for the same treatment period as used for Group D; Group G included cells irradiated in the reactor for the same treatment period as used for Group E; Group H included cells irradiated with 4 Gy in the reactor; and Group I included cells irradiated with 8 Gy in the reactor. Cell survival was determined using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium (MTT) cytotoxicity assay. The morphology of cells was detected by Hoechst33342 staining and transmission electron microscope (TEM). The apoptosis rate was detected by flow cytometer (FCM). The level of Bcl-2 and Bax protein was measured by western blot analysis.</p> <p>Results</p> <p>Proliferation of U87, U251, and SHG44 cells was much more strongly inhibited by BPA-BNCT than by irradiation with [<sup>60</sup>Co] γ-rays (<it>P </it>< 0.01). Nuclear condensation was determined using both a fluorescence technique and electron microscopy in all cell lines treated with BPA-BNCT. Furthermore, the cellular apoptotic rates in Group D and Group E treated with BPA-BNCT were significantly higher than those in Group B and Group C irradiated by [<sup>60</sup>Co] γ-rays (<it>P </it>< 0.01). The clonogenicity of glioma cells was reduced by BPA-BNCT compared with cells treated in the reactor (Group F, G, H, I), and with the control cells (<it>P </it>< 0.01). Upon BPA-BNCT treatment, the Bax level increased in glioma cells, whereas Bcl-2 expression decreased.</p> <p>Conclusions</p> <p>Compared with ��-ray and reactor neutron irradiation, a higher RBE can be achieved upon treatment of glioma cells with BNCT. Glioma cell apoptosis induced by BNCT may be related to activation of Bax and downregulation of Bcl-2.</p
The PB2 mutation with lysine at 627 enhances the pathogenicity of avian influenza (H7N9) virus which belongs to a non-zoonotic lineage
A novel avian-origin influenza A (H7N9) virus emerged in China in 2013 and has caused zoonotic disease in over 1123 persons with an overall mortality around 30%. Amino acid changes at the residues 591, 627 and 701 of polymerase basic protein 2 (PB2) have been found frequently in the human H7N9 isolates but not in viruses isolated from avian species. We have recently identified a cluster of H7N9 viruses in ducks which circulated in China prior to the first recognition of zoonotic disease in 2013. These duck viruses have genetic background distinct from the zoonotic H7N9 lineage. We found that the introduction of PB2 mutation with K at 627 but not K at 591 or N at 701 to the duck H7N9 virus led to increased pathogenicity in mice. We also found that the induction of pro-inflammatory cytokines including TNF-α, IP-10, MCP-1 and MIP-1α were associated with increased severity of infection. We conclude that introduction of the mammalian adaptation mutations into the PB2 gene of duck H7N9 viruses, which are genetically unrelated to the zoonotic H7N9 lineage, can also enhance pathogenicity in mice.published_or_final_versio
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