Heterosis is a prevalent phenomenon in nature and is widely found in animals and plants, but the molecular mechanism of heterosis is still unclear. As the model insect of Lepidoptera, Bombyx mori is ...an ideal material to carry out heterosis research. In current study, we employed proteomic and genetic cross approaches to globally identify differentially expressed proteins in parental silkworms JingSong and HaoYue and their F1 hybrids. The results showed that there were significant differences between hybrids and their parents. In all, 28 differentially expressed proteins were successfully identified through MALDI-TOF-TOF mass spectrometry and database searches. Interestingly, three silk-related proteins were also obtained and identified, including fibroin L-chain, Nd-sD mutant fibroin light chain and fibrohexamerin, which were further confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). Consistent trends were also found in other genes. Taken together, our work not only provides the theoretical basis for the study of molecular mechanism of heterosis, but also provides candidate proteins and genes for the improvement of yield of silkworm.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Two-photon fluorescence microscopy is a widely used noninvasive bioimaging technique because of unique advantages such as a large penetration depth and 3D mapping capability. Ideal two-photon ...fluorophores require large two-photon absorption cross sections and red emission with high quantum yields. Here we report red-emitting-dye-doped conjugated polymer nanoparticles that display high two-photon excitation brightness. In these nanoparticles, conjugated polymer (PFV) was chosen as a two-photon light-harvesting material, and red-emitting dyes (MgPc and Nile red) were chosen as the energy acceptors and red-emitting materials. Two-photon excitation fluorescence of MgPc and Nile red was enhanced by up to ∼53 and ∼240 times, respectively. We have successfully demonstrated the application of these conjugated polymer-based nanoparticles in two-photon excitation cancer cell imaging with an excellent contrast ratio. This concept could become a general approach to the preparation of two-photon excitation red-emitting materials for deep-tissue live-cell imaging with high contrast.
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IJS, KILJ, NUK, PNG, UL, UM
493.
Adaptive varying-coefficient linear models Fan, Jianqing; Yao, Qiwei; Cai, Zongwu
Journal of the Royal Statistical Society. Series B, Statistical methodology,
01/2003, Volume:
65, Issue:
1
Journal Article
Peer reviewed
Open access
Varying-coefficient linear models arise from multivariate nonparametric regression, non-linear time series modelling and forecasting, functional data analysis, longitudinal data analysis and others. ...It has been a common practice to assume that the varying coefficients are functions of a given variable, which is often called an index. To enlarge the modelling capacity substantially, this paper explores a class of varying-coefficient linear models in which the index is unknown and is estimated as a linear combination of regressors and/or other variables. We search for the index such that the derived varying-coefficient model provides the least squares approximation to the underlying unknown multidimensional regression function. The search is implemented through a newly proposed hybrid backfitting algorithm. The core of the algorithm is the alternating iteration between estimating the index through a one-step scheme and estimating coefficient functions through one-dimensional local linear smoothing. The locally significant variables are selected in terms of a combined use of the t-statistic and the Akaike information criterion. We further extend the algorithm for models with two indices. Simulation shows that the methodology proposed has appreciable flexibility to model complex multivariate nonlinear structure and is practically feasible with average modern computers. The methods are further illustrated through the Canadian mink-muskrat data in 1925-1994 and the pound-dollar exchange rates in 1974-1983.
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BFBNIB, FZAB, GIS, IJS, INZLJ, IZUM, KILJ, NLZOH, NMLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZRSKP
Background and Aims
Hepatitis C virus (HCV) leads to a high rate of chronic infection and T cell dysfunction. Although it is well known that chronic antigenic stimulation is a driving force for ...impaired T cell functions, the precise mechanisms underlying immune activation–induced T cell dysfunctions during HCV infection remain elusive.
Approach and Results
Here, we demonstrated that circulating CD4+ T cells from patients who are chronically HCV‐infected exhibit an immune activation status, as evidenced by the overexpression of cell activation markers human leukocyte antigen‐antigen D‐related, glucose transporter 1, granzyme B, and the short‐lived effector marker CD127‐ killer cell lectin‐like receptor G1+. In contrast, the expression of stem cell–like transcription factor T cell factor 1 and telomeric repeat‐binding factor 2 (TRF2) are significantly reduced in CD4+ T cells from patients who are chronically HCV‐infected compared with healthy participants (HP). Mechanistic studies revealed that CD4+ T cells from participants with HCV exhibit phosphoinositide 3‐kinase/Akt/mammalian target of rapamycin signaling hyperactivation on T cell receptor stimulation, promoting proinflammatory effector cell differentiation, telomeric DNA damage, and cellular apoptosis. Inhibition of Akt signaling during T cell activation preserved the precursor memory cell population and prevented inflammatory effector cell expansion, DNA damage, and apoptotic death. Moreover, knockdown of TRF2 reduced HP T cell stemness and triggered telomeric DNA damage and cellular apoptosis, whereas overexpression of TRF2 in CD4 T cells prevented telomeric DNA damage.
Conclusions
These results suggest that modulation of immune activation through inhibiting Akt signaling and protecting telomeres through enhancing TRF2 expression may open therapeutic strategies to fine tune the adaptive immune responses in the setting of persistent immune activation and inflammation during chronic HCV infection.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Display omitted
•A mechanism for MDSC expansion during sepsis is proposed.•The mecanism involves induction of miR-21 and miR-181b by C/EBPβ.•Inhibiting C/EBPβ expression can prevent MDSC expansion ...and sepsis immunosuppression.
Sepsis-induced myeloid-derived suppressor cells (MDSCs) contribute to immunosuppression associated with sepsis. We reported that the CCAAT enhancer-binding protein C/EBPβ activates microRNA (miR)-21 and miR-181b expressions, which induce transcription factor NFI-A to support the generation and expansion of MDSCs in the bone marrow and spleens of septic mice. Here, using a conditional knockout mouse model lacking C/EBPβ in the myeloid lineage, we find that without C/EBPβ, myeloid progenitor cells could not express miR-21 or miR-181b, and ectopic expression of C/EBPβ in the C/EBPβ-deficient myeloid progenitors activated the expression of the two miRNAs. Moreover, C/EBPβ-reconstituted myeloid cells expressed IL-10 and reduced T cell proliferation and function, similar to control MDSCs that express C/EBPβ. Exogenous expression of miR-21 and miR-181b in the C/EBPβ-deficient myeloid progenitors from septic mice produced similar results. Notably, NFI-A-dependent transactivation of NF-kB MDSC generating pathway was reversed in the C/EBPβ-deficient myeloid progenitors from septic mice. Together, these results support that decreasing C/EBPβ expression prevents MDSC generation and decreases immunosuppression in septic mice, providing a target for sepsis treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The hydrochemistry of arsenic and selenium in the Changjiang (Yangtze River) was studied, based on continuously monitored data at Nantong station (i.e. 180 km inland from river mouth), the main ...Changjiang channel and 10 major tributaries. The dissolved inorganic arsenic (DIAs) and selenium (DISe) concentrations of the Changjiang are related to water discharge, rock type of drain basin, anthropogenic influences etc. The DIAs and DISe levels vary over an order of magnitude throughout the basin (i.e. 6.95–68.9 nmol/L for DIAs, 1.16–9.92 nmol/L for DISe). Source rock composition is the primary control on the concentrations of DIAs and DISe in the Changjiang. Several tributaries (e.g. Xiangjiang River, Minjiang River and Tuojiang River) are contaminated by human activities. Flux calculations from hydrographic data at Datong (the most downstream main channel station without tidal influence) indicate that the Changjiang transports 234.8
×
10
5 mol/yr of DIAs and 49.6
×
10
5 mol/yr of DISe to the East China Sea.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To report the rate and spectrum of the rheumatic manifestations of human immunodeficiency virus (HIV) since the advent of highly active anti-retroviral therapy (HAART).
A retrospective record review ...of 888 inpatients with HIV for rheumatic manifestations was performed from January 1995 to March 2006. We then searched the 888 records for rheumatic diseases using International Classification Diagnostic (ICD) Codes. The medical records of the cases of HIV with the rheumatic conditions were then reviewed. A computer-assisted search of Medline/Pubmed for the medical literature from January 1981 to August 2007 using the keywords HIV, acquired immune-deficiency syndrome, rheumatic manifestations, combining with text words like systemic lupus erythematosus (SLE). Only English language literature was included.
The demographic data of 888 cases of HIV included men (64%) and women (36%) with a mean age of 41.5+/-10.2 years. Race consisted of Black (70%), White (22.8%), Hispanic (6.5%), and others (1.1%). Rheumatic manifestations were present in 80 (9%) with arthritis/arthralgia 49 (5.5%), septic arthritis 9 (1%), and osteomyelitis 8 (0.9%), connective tissue diseases (CTDs) 6 (0.7%) (SLE 3, rheumatoid arthritis 1, polymyositis 1, and systemic sclerosis 1), avascular necrosis 6 (0.7%) (hips 3, knees 2, and shoulder 1). There were no cases of seronegative spondyloarthritis or Sjögren's syndrome.
There was an association of HIV with rheumatic conditions in 9%, including CTDs and avascular necrosis. In addition, there were no cases of the seronegative spondyloarthritis subsets. This change in spectrum from prior reports suggests the rheumatic manifestations of HIV have changed, perhaps related to HAART.
We report observations of gamma-ray emissions with energies in the 100-TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directions of the Cygnus ...OB1 and OB2 associations. Based on their positional coincidences, we associate one with a pulsar PSR J2032 + 4127 and the other mainly with a pulsar wind nebula PWN G75.2 + 0.1, with the pulsar moving away from its original birthplace situated around the centroid of the observed gamma-ray emission. This work would stimulate further studies of particle acceleration mechanisms at these gamma-ray sources.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
Obstructive apneas and hypopneas during sleep are a well recognized cause of excessive daytime sleepiness. Snoring is also associated with excess sleepiness, although it is not known whether this ...reflects an independent effect of snoring or whether snoring is simply a marker for obstructive sleep apnea. To further explore the relation of snoring to sleepiness, we conducted a cross-sectional cohort study of community-dwelling adults participating in the Sleep Heart Health Study. The study sample comprises 2,737 men and 3,040 women with a mean age of 64 (SD 11) yr. Sleepiness was quantified using the Epworth Sleepiness Scale (ESS). Snoring history was obtained via a self-completion questionnaire. The respiratory disturbance index (RDI), defined as the number of apneas plus hypopneas per hour of sleep, was measured during in-home polysomnography. The ESS score increased progressively with increasing RDI, from a mean of 7.1 (4.2) in subjects with RDI < 1.5 to 8.8 (4.8) in subjects with RDI >/= 15 (p < 0.001). A progressive increase in ESS score was also seen across five categories of snoring frequency, from 6.4 (4.2) in current nonsnorers to 9.3 (4.8) in subjects who snored six to seven nights per week (p < 0.001). The prevalence of excessive daytime sleepiness, defined as an ESS score >/= 11, increased from 15% in never-snorers to 39% in those who snored six to seven nights per week. The relation of snoring to sleepiness was seen at all levels of RDI, with no significant change in the relation of snoring to ESS score after adjustment for RDI in multivariate models. The effects of snoring and RDI on sleepiness were little affected by adjustment for age, sex, race, body mass index, or questionnaire evidence of insufficient sleep time or nocturnal leg jerks or cramps. We conclude that both snoring and RDI are independently associated with excess sleepiness in community-dwelling, middle-aged and older adults.
Transverse vibration of a circular cross sectional micro-rod subjected to a new kind of boundary constraints with elastic torsional springs is presented based on nonlocal elasticity. A nonlocal ...strengthening beam model is utilized and the effect of temperature changing is taken into consideration. The variational method and Hamilton's principle are applied to derive the governing equation of motion and corresponding boundary conditions. A higher-order partial differential equation that is a typical characteristic of nonlocal strengthening model is developed, and the boundary conditions contain not only classical conditions but also non-classical higher-order conditions. Unlike previous studies which were only concerned with some conventional boundary constraints, we consider more general boundary conditions named elastic torsional spring supports. Such boundary conditions are between the simply supported and clamped ones, and they are closer to the actual constraints of existing engineering structures. Natural frequencies of micro-rods with new boundary constraints are determined via an eigenvalue method and compared with other results in the literature. It is shown that the nonlocal scale factor, thermal parameter, rigidity parameter and torsional spring coefficient play significant roles in free vibration of micro-rods. The research can provide a reference for a large class of boundary conditions ranging from simply supported to clamped micro-rods.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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