Hard Ticks as Vectors Tested Negative for Severe Fever with Thrombocytopenia Syndrome in Ganghwa-do,Korea during 2019–2020

This study aimed to characterize the seasonal abundance of hard ticks that transmit severe fever with thrombocytopenia syndrome virus from April to November 2019 and 2020 on Ganghwa-do, Incheon Metropolitan City, Korea. The ticks were collected at grassland, grave site, copse and mountain road using a collection trap method. The ixodid hard ticks comprising three species (Haemaphysalis longicornis, H. flava, and Ixodes nipponensis) collected were 6,622 in 2019 and 3,811 in 2020. H. longicornis was the most frequent (97.9% in 2019 and 96.0% in 2020), followed by H. flava (2.0% and 3.0% in 2019 and 2020, respectively) and I. nipponensis (less than 0.1%). Our study demonstrated that seasonal patterns of the tick populations examined for two years were totally unsimilar. The hard ticks tested using RT-qPCR were all negative for severe fever with thrombocytopenia syndrome virus.     

Carbon cycling within the sulfate-methane-transition-zone in marine sediments from the Ulleung Basin

The significance of the various carbon cycling pathways in driving the sharp sulfate methane transition zone (SMTZ) observed at many locations along continental margins is still a topic of debate. Unraveling these processes is important to our understanding of the carbon cycle in general and to evaluate whether the location of this front can be used to infer present and past methane fluxes from deep reservoirs (e.g., gas hydrate). Here we report the pore water data from the second Ulleung Basin Gas Hydrate Expedition and on the results of a box model that balances solute fluxes among different carbon pools and satisfies the observed isotopic signatures. Our analysis identifies a secondary methanogenesis pathway within the SMTZ, whereby 25–35 % of the dissolved inorganic carbon (DIC) produced by the anaerobic oxidation of methane (AOM) is consumed by CO₂ reduction (CR). To balance this DIC consumption, a comparable rate of organic matter degradation becomes necessary, which in turn consumes a significant amount of sulfate. The fraction of sulfate consumed by AOM ranges from 70 to 90 %. Whereas a simple mass balance would suggest a one to one relationship between sulfate and methane fluxes; our isotopic considerations show that methane flux estimates based solely on sulfate data may be in error by as much as 30 %. Furthermore, the carbon cycling within the SMTZ is fueled by a significant contribution (10–40 %) of methane produced by CR just below the SMTZ. Therefore sulfate gradient cannot necessarily be used to infer methane contributions from gas hydrate reservoirs that may lay tens to hundreds of meters below the SMTZ.     

An organ culture system to model early degenerative changes of the intervertebral disc

Introduction  

Back pain, a significant source of morbidity in our society, is related to the degenerative changes of the intervertebral disc. At present, the treatment of disc disease consists of therapies that are aimed at symptomatic relief. This shortcoming stems in large part from our lack of understanding of the biochemical and molecular events that drive the disease process. The goal of this study is to develop a model of early disc degeneration using an organ culture. This approach is based on our previous studies that indicate that organ culture closely models molecular events that occur in vivo in an ex vivo setting.     

Proteomic analysis of apoptosis related proteins regulated by proto‐oncogene protein DEK

A nuclear phosphoprotein, DEK, is implicated in certain human diseases, such as leukemia and antoimmune disorders, and a major component of metazoan chromatin. Basically as a modulator of chromatin structure, it can involve in various DNA and RNA‐dependent processes and function as either an activator or repressor. Despite of numerous efforts to suggest the biological role of DEK, direct target proteins of DEK in different physiological status remains elusive. To investigate if DEK protein triggers the changes in certain protein networks, DEK was knocked down at both types of cell clones using siRNA expression. Here we provide a catalogue of proteome profiles in total cell lysates derived from normal HeLa and DEK knock‐down HeLa cells and a good in vitro model system for dissecting the protein networks due to this proto‐oncogenic DEK protein. In this biological context, we compared total proteome changes by the combined methods of two‐dimensional gel electrophoresis, quantitative image analysis and MALDI‐TOF MS analysis. There were a large number of targets for DEK, which were differentially expressed in DEK knock‐down cells and consisted of 58 proteins (41 up‐regulated and 17 down‐regulated) differentially regulated expression was further confirmed for some subsets of candidates by Western blot analysis using specific antibodies. In the identified 58 spots, 16% of proteins are known to be associated with apoptosis. Among others, we identified apoptosis related proteins such as Annexins, Enolase1, Lamin A, and Glutathione‐S‐transferase omega 1. These results are consistent with recent studies indicating the crucial role of DEK in apoptosis pathway. We further demonstrated by ChIP analysis that knock‐down of DEK caused hyperacetylation of histones around Prx VI promoter which is upregulated in our profile. Using immunoblotting analysis, we have demonstrated the modulation of other caspase‐dependent apoptosis related proteins by DEK knock‐down and further implicate its role in apoptosis pathway. J. Cell. Biochem. 106: 1048–1059, 2009. © 2009 Wiley‐Liss, Inc.     

Study of the mitotic and meiotic chromosomes of sotol (<i>Dasylirion cedrosanum</i> Trel.)

The genus Dasylirion is a group of plants typically present in the Chihuahuan Desert, perennial, with a dioecious sexual behavior and commonly called sotoles. This genus has been little studied from the biological point of view, and the bases of its reproductive response remain unknown. In this work we studied the chromosome number and meiotic response of Dasylirion cedrosanum in the county of Saltillo, Coahuila, located at the North East of Mexico. For the preparation of mitotic chromosomes, we used a technique based on enzymatic treatment with pectolyase and cellulase, as well as staining with acetocarmin dye. For the study of meiosis, male flower buds were collected, fixed and stained for analysis with the same dye. As a result, the gametic (n = x = 19) and somatic chromosome (2n = 38) numbers of D. cedrosanum are reported for the first time, being consistent with previous findings in other Dasylirion species, which points to a constant ploidy level across the genus. Variation was observed in the morphology and size of the somatic chromosomes, with types ranging from submetacentric to subtelocentric, and sizes oscillating in a range of 4.43 µm, with an average total length of 112.38 µm for the diploid chromosome complement. This shows that the chromosome complement of D. cedrosanom would belong to a 3B classification of Stebins, with a medium variation between chromosome lengths and low chromosome asymmetry. This variation indicates the feasibility of constructing a chromosome ideotype for this species. The meiotic chromosome pairing showed a chromosome behavior consistent with a disomic inheritance characteristic of a diploid species, with prevalence of ring and chain bivalents, typically without pairing abnormalities. Bivalent configurations in all cases were symmetrical.The normal and symmetrical meiotic pairing indicates a balanced production of gametes, and suggests the absence of heteromorphic sex determination.     

Glyphosate-induced oxidative stress in rice leaves revealed by proteomic approach

Glyphosate is one of the most widely used herbicides in cereal-growing regions worldwide. In the present work, the protein expression profile of rice leaves exposed to glyphosate was analyzed in order to investigate the alternative effects of glyphosate on plants. Two-week-old rice leaves were subjected to glyphosate or a reactive oxygen species (ROS) inducing herbicide paraquat, and total soluble proteins were extracted and analyzed by two-dimensional gel electrophoresis (2-DE) coupled with matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) analysis. A total of 25 differentially expressed proteins were identified from the glyphosate treated sample, wherein 18 proteins were up-regulated and 7 proteins were down-regulated. These proteins had shown a parallel expression pattern in response to paraquat. Results from the 2-DE analysis, combined with immunoblotting, clearly revealed that ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) large subunit was significantly decreased by the treatment of both herbicides. An increased accumulation of antioxidant enzymes including ascorbate peroxidase, glutathione S-transferase, thioredoxin h-type, nucleoside diphosphate kinase 1, peroxiredoxin and a superoxide dismutase [Cu–Zn] chloroplast precursor in the glyphosate-treated sample suggests that a glyphosate treatment possibly generates oxidative stress in plants. Moreover, a gene expression analysis of five antioxidant enzymes by Northern blot confirmed their mRNA levels in the rice leaves. A histo-cytochemical investigation with DAB (3,3-diaminobenzidine) to localize H₂O₂ and increases of the thiobarbituric acid reactive substances (TBARS) concentration revealed that the glyphosate application generates ROS, which resulted in the peroxidation and destruction of lipids in the rice leaves.     

Anticapsid immunity level, not viral persistence level, correlates with the progression of Theiler's virus-induced demyelinating disease in viral P1-transgenic mice

Intracranial infection of Theiler's murine encephalomyelitis virus (TMEV) induces demyelination and a neurological disease in susceptible SJL/J (SJL) mice that resembles multiple sclerosis. While the virus is cleared from the central nervous system (CNS) of resistant C57BL/6 (B6) mice, it persists in SJL mice. To investigate the role of viral persistence and its accompanying immune responses in the development of demyelinating disease, transgenic mice expressing the P1 region of the TMEV genome (P1-Tg) were employed. Interestingly, P1-Tg mice with the B6 background showed severe reductions in both CD4(+) and CD8(+) T-cell responses to capsid epitopes, while P1-Tg mice with the SJL background displayed transient reductions following viral infection. Reduced antiviral immune responses in P1-Tg mice led to >100- to 1,000-fold increases in viral persistence at 120 days postinfection in the CNS of mice with both backgrounds. Despite the increased CNS TMEV levels in these P1-Tg mice, B6 P1-Tg mice developed neither neuropathological symptoms nor demyelinating lesions, and SJL P1-Tg mice developed significantly less severe TMEV-induced demyelinating disease. These results strongly suggest that viral persistence alone is not sufficient to induce disease and that the level of T-cell immunity to viral capsid epitopes is critical for the development of demyelinating disease in SJL mice.