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Interactions between clonal asparagus plantlets and virulent and avirulent isolates of Fusarium.
Fusarium oxysporum was isolated most frequently, followed by F. moniliforme, and F. solani from infected asparagus plants grown in the field. In pathogenicity tests both with seedlings and plantlets, F. moniliforme showed slightly higher virulence than Fusarium oxysporum did in general. Fusarium moniliforme showed more consistent virulence on both seedlings and plantlets than F. oxysporum did. Fusarium oxysporum showed slightly higher virulence on plantlets than on seedlings. Fusarium solani showed very weak or no sign of virulence on seedlings and plantlets, respectively, in both tests. In protection tests with plantlets, most protection of asparagus against virulent fusarial infections occurred when challenge isolates were inoculated five or seven days after inoculation of protective fusarial species. Avirulent F. oxysporum was a more effective protective agent against infection of F. moniliforme than it was against F. oxysporum. Fusarium solani was more effective against infection of F. oxysporum than it was against F. moniliforme. Virulent fusarial species showed significant increase in conidial populations on asparagus plantlet root and stem segments, and showed higher root and stem rot ratings than avirulent fusarial species did. Avirulent fusarial species showed minimal increase in conidial populations on both root and stem segments, and showed low to very low root and stem rot ratings. All fusarial species infected asparagus plantlets through primary and lateral root tips, natural wounds, and between the walls of the epidermal cells directly. Some penetration was appressorium-like and direct. It was assumed that the meristematic region could act as a major infection site. Virulent fusarial species were growing faster and more abundantly inside and outside of the plantlet epidermal areas than were avirulent fusarial species. Fusarium solani was the slowest growing species. Within a short period, virulent fusarial species caused cortical rots. However, over extended periods, they invaded tracheary elements eventually, and caused extensive damages. Avirulent F. oxysporum accumulated heavily on and around the epidermal areas even if it invaded part of cortical cells inside the epidermal regions. Fusarium solani caused proliferation of lateral roots and increased the surface area of primary and secondary roots
The involvement of GSK3β for glycogen synthesis throughout the annual cycle of Pacific oyster, Crassostrea gigas (Magallana gigas)
Crassostrea gigas is a frequently studied species in understanding physiological processes in bivalves. Similar to other animals, oysters store glucose in the body as glycogen. Glycogen is known to supply energy for germ cell development and maintenance. Glycogen is synthesized by glycogen synthase. GSK3β regulates glycogen synthase activity and plays an important role in glycogen synthesis. Therefore, this study aims to examine the effect of GSK3β on the annual cycle of oysters and the glycogen synthesis pathway and to investigate the energy pathway in comparison with seasonal variation. Oysters were sampled monthly for one year and were subjected to glycogen content, RT-PCR, FISH, and western blot analysis. The year-round glycogen content significantly differs only in the mantle edge during spring and summer of both sexes but not in labial palp, digestive gland, gonad, and adductor muscle. The expression of GSK3β mRNA level was highest in October for females and April for males. Both sexes had the lowest expression in July. In the adductor muscle, females and males showed the highest expression in April and the lowest in July and October. The pattern of GSK3β expression in gonads and adductor muscle was similarly confirmed through FISH. As a result of examining the signaling system, p-GSK3β (serine 9) increased. At the same time, glycogen synthase decreased in May when the condition index was the highest, p-GSK3β decreased in October and July when spawning occurred, and glycogen synthase increased. Overall, it is thought that p-GSK3β expression is high in C. gigas at ripe, which inhibits glycogen synthesis and is used as energy for growth and maturation. Glycogen synthesis occurs for energy storage during degeneration
Dynamic Correlation between Intrahost HIV-1 Quasispecies Evolution and Disease Progression
Quantifying the dynamics of intrahost HIV-1 sequence evolution is one means
of uncovering information about the interaction between HIV-1 and the host
immune system. In the chronic phase of infection, common dynamics of
sequence divergence and diversity have been reported. We developed an HIV-1
sequence evolution model that simulated the effects of mutation and fitness
of sequence variants. The amount of evolution was described by the distance
from the founder strain, and fitness was described by the number of
offspring a parent sequence produces. Analysis of the model suggested that
the previously observed saturation of divergence and decrease of diversity
in later stages of infection can be explained by a decrease in the
proportion of offspring that are mutants as the distance from the founder
strain increases rather than due to an increase of viral fitness. The
prediction of the model was examined by performing phylogenetic analysis to
estimate the change in the rate of evolution during infection. In agreement
with our modeling, in 13 out of 15 patients (followed for 3–12
years) we found that the rate of intrahost HIV-1 evolution was not constant
but rather slowed down at a rate correlated with the rate of
CD4+ T-cell decline. The correlation between the dynamics of the
evolutionary rate and the rate of CD4+ T-cell decline, coupled
with our HIV-1 sequence evolution model, explains previously conflicting
observations of the relationships between the rate of HIV-1 quasispecies
evolution and disease progression
Chronic Treatment with Squid Phosphatidylserine Activates Glucose Uptake and Ameliorates TMT-Induced Cognitive Deficit in Rats via Activation of Cholinergic Systems
The present study examined the effects of squid phosphatidylserine (Squid-PS) on the learning and memory function and the neural activity in rats with TMT-induced memory deficits. The rats were administered saline or squid derived Squid-PS (Squid-PS 50 mg kg−1, p.o.) daily for 21 days. The cognitive improving efficacy of Squid-PS on the amnesic rats, which was induced by TMT, was investigated by assessing the passive avoidance task and by performing choline acetyltransferase (ChAT) and acetylcholinesterase (AchE) immunohistochemistry. 18F-Fluorodeoxyglucose and performed a positron emission tomography (PET) scan was also performed. In the passive avoidance test, the control group which were injected with TMT showed a markedly lower latency time than the non-treated normal group (P < 0.05). However, treatment of Squid-PS significantly recovered the impairment of memory compared to the control group (P < 0.05). Consistent with the behavioral data, Squid-PS significantly alleviated the loss of ChAT immunoreactive neurons in the hippocampal CA3 compared to that of the control group (P < 0.01). Also, Squid-PS significantly increased the AchE positive neurons in the hippocampal CA1 and CA3. In the PET analysis, Squid-PS treatment increased the glucose uptake more than twofold in the frontal lobe and the hippocampus (P < 0.05, resp.). These results suggest that Squid-PS may be useful for improving the cognitive function via regulation of cholinergic enzyme activity and neural activity
Mycobiota community and fungal species response to development stage and fire blight disease in apples
Fire blight disease, caused by the bacterial pathogen Erwinia amylovora, has been a significant concern for over 50 countries worldwide. The efficacy of chemical pesticides currently available for disease control is limited. To address this issue, research is being conducted to explore environmentally friendly control methods, particularly biological control using beneficial microorganisms. However, there is limited research on the apple microbiota community and minimal research has been conducted on fungal communities that may exhibit reliable performance in apple trees. Therefore, our objective was to analyze the fungal communities present in apples at different developmental stages and in different tissues, aiming to identify potential biological control agents for fire blight disease. Our findings indicate that the fungal communities present in apple buds, flowers and leaves play an important role in inhibiting the invasion of E. amylovora. Specifically, we propose GS11 and Lipomyces starkeyi as potential keystone taxa that respond to fire blight disease. These findings provide insights into the continuity and discontinuity of fungal community structure in different developmental stages of apples and offer predictions for potential biological control agents for fire blight disease
Comprehensive Proteome Profiling of Platelet Identified a Protein Profile Predictive of Responses to An Antiplatelet Agent Sarpogrelate
Sarpogrelate is an antiplatelet agent widely used to treat arterial occlusive diseases. Evaluation of platelet aggregation is essential to monitor therapeutic effects of sarpogrelate. Currently, no molecular signatures are available to evaluate platelet aggregation. Here, we performed comprehensive proteome profiling of platelets collected from 18 subjects before and after sarpogrelate administration using LC-MS/MS analysis coupled with extensive fractionation. Of 5423 proteins detected, we identified 499 proteins affected by sarpogrelate and found that they strongly represented cellular processes related to platelet activation and aggregation, including cell activation, coagulation, and vesicle-mediated transports. Based on the network model of the proteins involved in these processes, we selected three proteins (cut-like homeobox 1; coagulation factor XIII, B polypeptide; and peptidylprolyl isomerase D) that reflect the platelet aggregation-related processes after confirming their alterations by sarpogrelate in independent samples using Western blotting. Our proteomic approach provided a protein profile predictive of therapeutic effects of sarpogrelate. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.1
Induction of IL-10-producing CD4(+)CD25(+ )T cells in animal model of collagen-induced arthritis by oral administration of type II collagen
Induction of oral tolerance has long been considered a promising approach to the treatment of chronic autoimmune diseases, including rheumatoid arthritis (RA). Oral administration of type II collagen (CII) has been proven to improve signs and symptoms in RA patients without troublesome toxicity. To investigate the mechanism of immune suppression mediated by orally administered antigen, we examined changes in serum IgG subtypes and T-cell proliferative responses to CII, and generation of IL-10-producing CD4(+)CD25(+ )T-cell subsets in an animal model of collagen-induced arthritis (CIA). We found that joint inflammation in CIA mice peaked at 5 weeks after primary immunization with CII, which was significantly less in mice tolerized by repeated oral feeding of CII before CIA induction. Mice that had been fed with CII also exhibited increased serum IgG(1 )and decreased serum IgG(2a )as compared with nontolerized CIA animals. The T-cell proliferative response to CII was suppressed in lymph nodes of tolerized mice also. Production of IL-10 and of transforming growth factor-β from mononuclear lymphocytes was increased in the tolerized animals, and CD4(+ )T cells isolated from tolerized mice did not respond with induction of IFN-γ when stimulated in vitro with CII. We also observed greater induction of IL-10-producing CD4(+)CD25(+ )subsets among CII-stimulated splenic T cells from tolerized mice. These data suggest that when these IL-10-producing CD4(+)CD25(+ )T cells encounter CII antigen in affected joints they become activated to exert an anti-inflammatory effect
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