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901.
David Yang-Wei Fann Yun-An Lim Yi-Lin Cheng Ker-Zhing Lok Prasad Chunduri Sang-Ha Baik Grant R. Drummond S. Thameem Dheen Christopher G. Sobey Dong-Gyu Jo Christopher Li-Hsian Chen Thiruma V. Arumugam 《Molecular neurobiology》2018,55(2):1082-1096
Multi-protein complexes, termed “inflammasomes,” are known to contribute to neuronal cell death and brain injury following ischemic stroke. Ischemic stroke increases the expression and activation of nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) Pyrin domain containing 1 and 3 (NLRP1 and NLRP3) inflammasome proteins and both interleukin (IL)-1β and IL-18 in neurons. In this study, we provide evidence that activation of either the NF-κB and MAPK signaling pathways was partly responsible for inducing the expression and activation of NLRP1 and NLRP3 inflammasome proteins and that these effects can be attenuated using pharmacological inhibitors of these two pathways in neurons and brain tissue under in vitro and in vivo ischemic conditions, respectively. Moreover, these findings provided supporting evidence that treatment with intravenous immunoglobulin (IVIg) preparation can reduce activation of the NF-κB and MAPK signaling pathways resulting in decreased expression and activation of NLRP1 and NLRP3 inflammasomes, as well as increasing expression of anti-apoptotic proteins, Bcl-2 and Bcl-xL, in primary cortical neurons and/or cerebral tissue under in vitro and in vivo ischemic conditions. In summary, these results provide compelling evidence that both the NF-κB and MAPK signaling pathways play a pivotal role in regulating the expression and activation of NLRP1 and NLRP3 inflammasomes in primary cortical neurons and brain tissue under ischemic conditions. In addition, treatment with IVIg preparation decreased the activation of the NF-κB and MAPK signaling pathways, and thus attenuated the expression and activation of NLRP1 and NLRP3 inflammasomes in primary cortical neurons under ischemic conditions. Hence, these findings suggest that therapeutic interventions that target inflammasome activation in neurons may provide new opportunities in the future treatment of ischemic stroke. 相似文献
902.
Genome-wide association study identified genetic variations and candidate genes for plant architecture component traits in Chinese upland cotton 总被引:1,自引:0,他引:1
Junji Su Libei Li Chi Zhang Caixiang Wang Lijiao Gu Hantao Wang Hengling Wei Qibao Liu Long Huang Shuxun Yu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(6):1299-1314
Key message
Thirty significant associations between 22 SNPs and five plant architecture component traits in Chinese upland cotton were identified via GWAS. Four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits. A candidate gene, Gh_D03G0922, might be responsible for plant height in upland cotton.Abstract
A compact plant architecture is increasingly required for mechanized harvesting processes in China. Therefore, cotton plant architecture is an important trait, and its components, such as plant height, fruit branch length and fruit branch angle, affect the suitability of a cultivar for mechanized harvesting. To determine the genetic basis of cotton plant architecture, a genome-wide association study (GWAS) was performed using a panel composed of 355 accessions and 93,250 single nucleotide polymorphisms (SNPs) identified using the specific-locus amplified fragment sequencing method. Thirty significant associations between 22 SNPs and five plant architecture component traits were identified via GWAS. Most importantly, four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits, and these SNPs were harbored in one linkage disequilibrium block. Furthermore, 21 candidate genes for plant architecture were predicted in a 0.95-Mb region including the four peak SNPs. One of these genes (Gh_D03G0922) was near the significant SNP D03_31584163 (8.40 kb), and its Arabidopsis homologs contain MADS-box domains that might be involved in plant growth and development. qRT-PCR showed that the expression of Gh_D03G0922 was upregulated in the apical buds and young leaves of the short and compact cotton varieties, and virus-induced gene silencing (VIGS) proved that the silenced plants exhibited increased PH. These results indicate that Gh_D03G0922 is likely the candidate gene for PH in cotton. The genetic variations and candidate genes identified in this study lay a foundation for cultivating moderately short and compact varieties in future Chinese cotton-breeding programs.903.
904.
Paced QRS morphology predicts incident left ventricular systolic dysfunction and atrial fibrillation
Martin van Zyl Chance M. Witt Subir Bhatia Majd Khasawneh Prakriti Gaba Charles J. Lenz Andrew N. Rosenbaum Htin Aung David O. Hodge Christopher J. McLeod Samuel J. Asirvatham 《Indian pacing and electrophysiology journal》2019,19(2):40-46
Background
The prognostic significance of paced QRS complex morphology on surface ECG remains unclear. This study aimed to assess long-term outcomes associated with variations in the paced QRS complex.Methods
Adult patients who underwent dual-chamber pacemaker implantation with 20% or more ventricular pacing and a 12-lead ECG showing a paced complex were included. The paced QRS was analyzed in leads I and aVL. Long-term clinical and echocardiographic outcomes were compared at 5 years.Results
The study included 844 patients (43.1% female; age 75.0?±?12.1). Patients with a longer paced QRS (pQRS) duration in lead I had a lower rate of atrial fibrillation (HR 0.80; p?=?0.03) and higher rate of systolic dysfunction (HR 1.17; p?<?0.001). Total pacing complex (TPC) duration was linked to higher rates of ICD implantation (HR 1.18; p?=?0.04) and systolic dysfunction (HR 1.22, p?<?0.001). Longer paced intrinsicoid deflection (pID) was associated with less atrial fibrillation (HR 0.75; p?=?0.01), more systolic dysfunction (HR 1.17; p?<?0.001), ICD implantation (HR 1.23; p?=?0.04), and CRT upgrade (HR 1.23; p?=?0.03). Exceeding thresholds for TPC, pQRS, and pID of 170, 146, and 112?ms in lead I, respectively, was associated with a substantial increase in systolic dysfunction over 5 years (p?<?0.001).Conclusions
Longer durations of all tested parameters in lead I were associated with increased rates of left ventricular systolic dysfunction. ICD implantation and CRT upgrade were also linked to increased TPC and pID durations. Paradoxically, patients with longer pID and pQRS had less incident atrial fibrillation. 相似文献905.
Giovanna Della Porta Jeroen A. M. Kenter Juan R. Bahamonde Adrian Immenhauser Elisa Villa 《Facies》2003,49(1):175-207
Summary The Carboniferous, particularly during the Serpukhovian and Bashkirian time, was a period of scarce shallow-water calcimicrobial-microbialite
reef growth. Organic frameworks developed on high-rising platforms are, however, recorded in the Precaspian Basin subsurface,
Kazakhstan, Russia, Japan and Spain and represent uncommon occurrences within the general trend of low accumulation rates
and scarcity of shallow-water reefs. Sierra del Cuera (Cantabrian Mountains, N Spain) is a well-exposed high-rising carbonate
platform of Late Carboniferous (Bashkirian-Moscovian) age with a microbial boundstone-dominated slope dipping from 20° up
to 45°. Kilometer-scale continuous exposures allow the detailed documentation of slope geometry and lithofacies spatial distribution.
This study aims to develop a depositional model of steep-margined Late Paleozoic platforms built by microbial carbonates and
to contribute to the understanding of the controlling factors on lithofacies characteristics, stacking patterns, accumulation
rates and evolution of the depositional architecture of systems, which differ from light-dependent coralgal platform margins.
From the platform break to depths of nearly 300 m, the slope is dominated by massive cement-rich boundstone, which accumulated
through the biologically induced precipitation of micrite. Boundstone facies (type A) with peloidal carbonate mud, fenestellid
and fistuliporid bryozoans, sponge-like molds and primary cavities filled by radiaxial fibrous cement occurs all over the
slope but dominates the deeper settings. Type B boundstone consists of globose centimeter-scale laminated accretionary structures,
which commonly host botryoidal cement in growth cavities. The laminae nucleate around fenestellid bryozoans, sponges, Renalcis and Girvanella-like filaments. Type B boundstone typically occurs at depths between 20–150 m to locally more than 300 m and forms the bulk
of the Bashkirian prograding slope. The uppermost slope boundstone (type C; between 0 and 20–100 m depth) includes peloidal
micrite, radiaxial fibrous cement, bryozoans, sponge molds, Donezella, Renalcis, Girvanella, Ortonella, calcareous algae and calcitornellid foraminifers.
From depths of 80–200 m to 450 m, 1–30 m thick lenses of crinoidal packstone, spiculitic wackestone, and bryozoan biocementstone
with red-stained micrite matrix are episodically intercalated with boundstone and breccias. These layers increase in number
from the uppermost Bashkirian to the Moscovian in parallel with the change from a rapidly prograding to an aggrading architecture.
The red-stained strata share comparable features with Lower Carboniferous deeper-water mud-mound facies and were deposited
during relative rises of sea level and pauses in boundstone production. Rapid relative sea-level rises might have been associated
with changes in oceanographic conditions not favourable for thecalcimicrobial boundstone growth, such as upwelling of colder,
nutrient-rich waters lifting the thermocline to depths of 80–200 m.
Downslope of 150–300 m, boundstones interfinger with layers of matrix-free breccias, lenses of matrix-rich breccias, platform-
and slope-derived grainstone and crinoidal packstone. Clast-supported breccias bound by radiaxial cement are produced by rock
falls and avalanches coeval to boundstone growth. Matrix-rich breccias are debris flow deposits triggered by the accumulation
of red-stained layers. Debris flows develop following the relative sea-level rises, which favour the deposition of micrite-rich
lithofacies on the slope rather than being related to relative sea-level falls and subaerial exposures. The steep slope angles
are the result of in situ growth and rapid stabilization by marine cement in the uppermost part, passing into a detrital talus, which rests at the
angle of repose of noncohesive material. In the Moscovian, the aggradational architecture and steeper clinoforms are the result
of increased accommodation space due to tectonic subsidence and due to a reduction of slope accumulation rates (from 240±45−605±35
m/My to 130±5 m/My). The increasing number of red-stained layers and the decrease of boundstone productivity are attributed
to environmental changes in the adjacent basin, in particular during relative rises of sea level and to possible cooling due
to icehouse conditions. The geometry of the depositional system appears to be controlled by boundstone growth rates. During
the Bashkirian, the boundstone growth potential is at least 10 times greater than average values for ancient carbonate systems.
The slope progradation rates (nearly 400–1000 m/My) are similar to the highest values deduced for the Holocene Bahamian prograding
platform margin. The fundamental differences with modern systems are that progradation of the microbial-boundstone dominated
steep slope is primarily controlled by boundstone growth rates rather than by highstand shedding from the platform top and
that boundstone growth is largely independent from light and controlled by the physicochemical characteristics of seawater. 相似文献
906.
Nakul C. Maiti Takeshi Tomita Teizo Kitagawa Ken Okamoto Takeshi Nishino 《Journal of biological inorganic chemistry》2003,8(3):327-333
Resonance Raman spectra were investigated for the sulfo and desulfo forms of cow's milk xanthine oxidase, with various visible excitation lines between 400 and 650 nm, and Mo(VI)-ligand vibrations were observed for the first time. The Mo(VI)=S stretch was identified at 474 and 462 cm(-1 )for the (32)S- and (34)S-sulfo forms, respectively, but was absent in the reduced state and in the desulfo form. The Mo(VI)=O stretch was weakly observed at 899 cm(-1 )for the sulfo form and shifted to 892 cm(-1) with very weak intensity for the dioxo desulfo form. In measurements of an excitation profile, the two bands at 474 and 899 cm(-1) showed maximum intensity at similar excitation wavelengths, suggesting that the Raman intensity of the metal-ligand modes is due to the Mo(VI)<--S charge transfer transition, and that this is the origin of the intrinsically weak features of the Mo(VI)-ligand Raman bands. When the sulfo form was regenerated from the desulfo form, the 899 cm(-1) band reappeared. However, the band at 899 cm(-1) showed no frequency shift when regeneration was conducted in H(2)(18)O, or after several turnovers in the presence of xanthine in H(2)(18)O. When the sulfo form was reduced and reoxidized in H(2)(18)O buffer, the 899 cm(-1) band reappeared without any frequency shift. These observations suggest that the oxo oxygen in the Mo center of xanthine oxidase is not labile. Low-frequency vibrations of the Mo center were observed together with those of the Fe(2)S(2) center with some overlaps, while FAD modes were observed clearly. The absence of dithiolene modes in XO is in contrast to the Mo(VI) centers of DMSO reductase and sulfite oxidase. 相似文献
907.
We investigated the effects of estradiol-treated females on the behavior of male budgerigars. In comparison to control females,
females given implants of estradiol showed elevated nest behavior and darker cere color, which are characteristics of breeding
females. After we confirmed the efficacy of estradiol treatment on behavior and morphology, each female was paired with a
male mate. Males paired with estradiol-treated females showed more courtship behavior (auditory and visual display, and courtship
feeding) to their mates than males paired with control females. These data indicate that budgerigar females with a high estrogen
level enhance males' courtship behavior. Since males did not show response to estradiol-treated females soon after females
were introduced, effects of estradiol-treated female budgerigars may be mediated by the endocrine system, rather than wholly
by the nervous system, of males.
Electronic Publication 相似文献
908.
Behrsing HP Vickers AE Tyson CA 《Biochemical and biophysical research communications》2003,312(1):209-213
Precision-cut liver slices are reportedly limited as toxicity models by their short half-life in culture. We used traditional clinical chemistry biomarkers and histology to assess a newer procedure for improved liver slice maintenance. Slices from Sprague-Dawley rat livers were well maintained in a roller culture system for up to 10 days based on protein content (60-70% or higher of initial values) and biomarker retention and verified by histological examination of the tissues showing morphological integrity and viability of hepatocyte and biliary regions. Exposure of the slices to geldanamycin (GEL) resulted in loss of slice LDH and transaminase content, with associated depression in ALP and GGT levels and elevated bilirubin, indicating that GEL affects both cell types as occurs in vivo with this hepatobiliary toxicant. Thus, we conclude that liver slices merit further investigation as a general model for chronic as well as acute toxicity studies. 相似文献
909.
Yahaya Adam Giuliano Cecchi Patrick M. Kgori Tanguy Marcotty Charles I. Mahama Martin Abavana Benita Anderson Massimo Paone Raffaele Mattioli Jérémy Bouyer 《PLoS neglected tropical diseases》2013,7(3)
Background
An integrated strategy of intervention against tsetse flies was implemented in the Upper West Region of Ghana (9.62°–11.00° N, 1.40°–2.76° W), covering an area of ≈18,000 km2 within the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign. Two species were targeted: Glossina tachinoides and Glossina palpalis gambiensis.Methodology/Principal Findings
The objectives were to test the potentiality of the sequential aerosol technique (SAT) to eliminate riverine tsetse species in a challenging subsection (dense tree canopy and high tsetse densities) of the total sprayed area (6,745 km2) and the subsequent efficacy of an integrated strategy including ground spraying (≈100 km2), insecticide treated targets (20,000) and insecticide treated cattle (45,000) in sustaining the results of tsetse suppression in the whole intervention area. The aerial application of low-dosage deltamethrin aerosols (0.33–0.35 g a.i/ha) was conducted along the three main rivers using five custom designed fixed-wings Turbo thrush aircraft. The impact of SAT on tsetse densities was monitored using 30 biconical traps deployed from two weeks before until two weeks after the operations. Results of the SAT monitoring indicated an overall reduction rate of 98% (from a pre-intervention mean apparent density per trap per day (ADT) of 16.7 to 0.3 at the end of the fourth and last cycle). One year after the SAT operations, a second survey using 200 biconical traps set in 20 sites during 3 weeks was conducted throughout the intervention area to measure the impact of the integrated control strategy. Both target species were still detected, albeit at very low densities (ADT of 0.27 inside sprayed blocks and 0.10 outside sprayed blocks).Conclusions/Significance
The SAT operations failed to achieve elimination in the monitored section, but the subsequent integrated strategy maintained high levels of suppression throughout the intervention area, which will contribute to improving animal health, increasing animal production and fostering food security. 相似文献910.
Seasonal Bacterial Production in a Dimictic Lake as Measured by Increases in Cell Numbers and Thymidine Incorporation 总被引:4,自引:13,他引:4 下载免费PDF全文
Rates of primary and bacterial production in Little Crooked Lake were calculated from the rates of incorporation of H14CO3− and [methyl-3H]thymidine, respectively. Growth rates of bacteria in diluted natural samples were determined for epilimnetic and metalimnetic bacterial populations during the summers of 1982 and 1983. Exponential growth was observed in these diluted samples, with increases in cell numbers of 30 to 250%. No lag was observed in bacterial growth in 14 of 16 experiments. Correlation of bacterial growth rates to corresponding rates of thymidine incorporation by natural samples produced a conversion factor of 2.2 × 1018 cells produced per mole of thymidine incorporated. The mass of the average bacterial cell in the lake was 1.40 × 10−14 ± 0.05 × 10−14 g of C cell−1. Doubling times of natural bacteria calculated from thymidine incorporation rates and in situ cell numbers ranged from 0.35 to 12.00 days (median, 1.50 days). Bacterial production amounted to 66.7 g of C m−2 from April through September, accounting for 29.4% of total (primary plus bacterial) production during this period. The vertical and seasonal distribution of bacterial production in Little Crooked Lake was strongly influenced by the distribution of primary production. From April through September 1983, the depth of maximum bacterial production rates in the water column was related to the depth of high rates of primary production. On a seasonal basis, primary production increased steadily from May through September, and bacterial production increased from May through August and then decreased in September. 相似文献