157 research outputs found
Direct rosiglitazone action on steroidogenesis and proinflammatory factor production in human granulosa-lutein cells
<p>Abstract</p> <p>Background</p> <p>Ovarian granulosa cells are the predominant source of estradiol and progesterone biosynthesis in vivo. Rosiglitazone, a synthetic agonist of the peroxisome proliferator-activated receptor gamma (PPAR gamma), is applied as the treatment of insulin resistance including women with PCOS. The aim of the study was to investigate the direct effects of rosiglitazone on steroidogenesis and proinflammatory factor production in human granulosa-lutein cells (GLCs).</p> <p>Methods</p> <p>Primary human GLCs were separated during in vitro fertilization and cultured in the presence of rosiglitazone, GW9662 (an antagonist of PPAR gamma) and hCG. The mRNA expression of key steroidogenic factors including 3beta- hydroxysteriod dehydrogenase (3beta-HSD), cytochrome P-450 scc (CYP11A1), cytochrome P-450 aromatase (CYP19A1), and steroidogenic acute regulatory protein (StAR) were detected by quantitative real-time PCR. Estradiol and progesterone levels in GLCs cultures were measured by chemiluminescence immunoassay, and the proinflammtory factors (TNFalpha and IL-6) in conditioned culture media were measured by ELISA.</p> <p>Results</p> <p>PPAR gamma mRNA levels increased up to 3.24 fold by rosiglitazone at the concentration of 30 microM compared to control (P < 0.05). hCG alone or hCG with rosiglitazone had no significant effects on PPAR gamma mRNA levels. The CYP19A1 mRNA level at exposure to rosiglitazone alone showed a drop, but was not significantly reduced comparing to control. The expression levels of enzymes 3beta-HSD and CYP11A1 in all treatments did not alter significantly. The StAR mRNA expression at exposure to rosiglitazone was significantly increased comparing to control (P < 0.05). The media concentrations of E2 and progesterone by rosiglitazone treatment showed a declining trend comparing to control or cotreatment with hCG, which did not reach significance. Most importantly, treatment with rosiglitazone decreased TNFalpha secretion in a statistically significant manner compared with control (P < 0.05). The concentration of IL-6 following rosiglitazone exposure did not significantly decrease comparing to control.</p> <p>Conclusion</p> <p>In cultured GLCs, rosiglitazone stimulated StAR expression, but did not significantly affect steroidogenic enzymes, as well as E2 and progesterone production. Moreover, rosiglitazone significantly decreased the production of TNFalpha in human GLCs, suggesting that PPAR gamma may play a role in the regulation of GLCs functions through inhibiting proinflammatory factors.</p
Comparison of broiler performance, carcass yields and intestinal microflora when fed diets containing transgenic (Mon-40-3-2) and conventional soybean meal
This study was conducted to analyze the effects of transgenic glyphosate-tolerant soybeans on the performance, carcass yields and intestinal microflora of broiler chickens. Three hundred and sixty oneday- old Abor Aerec broilers were randomly divided into two dietary treatments, adding genetically modified (GM) glyphosate-tolerant soybean meal or conventional soybean meal, respectively. Broiler body weight and feed intake were recorded at regular intervals (day 0, 21 and 42). Chickens were slaughtered at day 42 for carcass yield measurement and sampling. Diversity of the ileum and cecum microflora was determined by denaturing gradient gel electrophoresis (DGGE) technique and DNA sequencing. No treatment differences (P > 0.05) were detected among dietary treatments for any measured performance and carcass parameters. The microbial population in ileum and cecum also had no significant difference between the two treatments (P>0.05). The similarity of the total ileum and cecum microflora between the two treatments was about 62 and 58%, respectively. The DNA-DGGE electrophoresis pattern bands of intestine microbe were divided into two groups because of the different diet. Fifteen DGGE DNA bands were identified, of which five of them were identified as known bacteria. The current study showed that there were no adverse effects of the transgenic soybean meal on the intestinal microflora of broilers.Key words: Broiler, glyphosate-tolerant soybean meal, intestinal microbiota, feed safety
Silencing an essential gene involved in infestation and digestion in grain aphid through plant‐mediated RNA interference generates aphid‐resistant wheat plants
Letter to the edito
A Magnetically and Thermally Controlled Liquid Metal Variable Stiffness Material
Smart materials that can actively tune their stiffness are of great interest to many fields, including the construction industry, medical devices, industrial machines, and soft robotics. However, developing a material that can offer a large range of stiffness change and rapid tuning remains a challenge. Herein, a liquid metal variable stiffness material (LMVSM) that can actively and rapidly tune its stiffness by applying an external magnetic field or by changing the temperature is developed. The LMVSM is composed of three layers: a gallium–iron magnetorheological fluid (Ga–Fe MRF) layer for providing variable stiffness, a nickel–chromium wire layer for Joule heating, and a soft heat dissipation layer for accelerating heating and rapid cooling. The stiffness can be rapidly increased by 4 times upon the application of a magnetic field or 10 times by solidifying the Ga–Fe MRF. Finally, the LMVSM is attached to a pneumatically controlled soft robotic gripper to actively tune its load capacity, demonstrating its potential to be further developed into smart components that can be widely adopted by smart devices
Red Alarm for Pre-trained Models: Universal Vulnerability to Neuron-Level Backdoor Attacks
Pre-trained models (PTMs) have been widely used in various downstream tasks.
The parameters of PTMs are distributed on the Internet and may suffer backdoor
attacks. In this work, we demonstrate the universal vulnerability of PTMs,
where fine-tuned PTMs can be easily controlled by backdoor attacks in arbitrary
downstream tasks. Specifically, attackers can add a simple pre-training task,
which restricts the output representations of trigger instances to pre-defined
vectors, namely neuron-level backdoor attack (NeuBA). If the backdoor
functionality is not eliminated during fine-tuning, the triggers can make the
fine-tuned model predict fixed labels by pre-defined vectors. In the
experiments of both natural language processing (NLP) and computer vision (CV),
we show that NeuBA absolutely controls the predictions for trigger instances
without any knowledge of downstream tasks. Finally, we apply several defense
methods to NeuBA and find that model pruning is a promising direction to resist
NeuBA by excluding backdoored neurons. Our findings sound a red alarm for the
wide use of PTMs. Our source code and models are available at
\url{https://github.com/thunlp/NeuBA}
Novel multiple RIS-assisted communications for 6G networks
As an emerging technique, reconfigurable intelligent surface (RIS) has recently received extensive attention and can be considered as a key enabling technology for future sixth generation (6G) wireless communication networks. In this letter, we propose a novel multiple RIS-assisted single-input-single-output (SISO) wireless communication system working in a domino pattern when obscuration is severe. The upper bound of the ergodic capacity and the outage probability for the proposed system are analyzed and the corresponding closed-form expressions are provided under Nakagami-m fading channels. The general multiple RIS-assisted systems including two RISs and K RISs are analyzed. Numerical results indicate that the number of RISs, the number of RIS elements, and the communication environment can significantly affect the upper bound of the ergodic capacity and the outage probability performance of the proposed system. The feasibility of the proposed system and the accuracy of the upper bound of the ergodic capacity and the outage probability are also verified by the numerical results
In-Orbit Instrument Performance Study and Calibration for POLAR Polarization Measurements
POLAR is a compact space-borne detector designed to perform reliable
measurements of the polarization for transient sources like Gamma-Ray Bursts in
the energy range 50-500keV. The instrument works based on the Compton
Scattering principle with the plastic scintillators as the main detection
material along with the multi-anode photomultiplier tube. POLAR has been
launched successfully onboard the Chinese space laboratory TG-2 on 15th
September, 2016. In order to reliably reconstruct the polarization information
a highly detailed understanding of the instrument is required for both data
analysis and Monte Carlo studies. For this purpose a full study of the in-orbit
performance was performed in order to obtain the instrument calibration
parameters such as noise, pedestal, gain nonlinearity of the electronics,
threshold, crosstalk and gain, as well as the effect of temperature on the
above parameters. Furthermore the relationship between gain and high voltage of
the multi-anode photomultiplier tube has been studied and the errors on all
measurement values are presented. Finally the typical systematic error on
polarization measurements of Gamma-Ray Bursts due to the measurement error of
the calibration parameters are estimated using Monte Carlo simulations.Comment: 43 pages, 30 figures, 1 table; Preprint accepted by NIM
Risk Factors and Medico-Economic Effect of Pancreatic Fistula after Pancreaticoduodenectomy
The study aimed to uncover the risk factors for the new defined pancreatic fistula (PF) and clinical related PF (CR-PF) after pancreaticoduodenectomy (PD) surgery and to evaluate the medico-economic effect of patients. A total of 412 patients were classified into two groups according to different criteria, PF and NOPF according to PF occurrence: CR-PF (grades B and C) and NOCR-PF (grade A) based on PF severity. A total of 28 factors were evaluated by univariate and multivariate logistic regression test. Hospital charges and stays of these patients were assessed. The results showed that more hospital stages and charges are needed for patients in PF and CR-PF groups than in NOPF and NOCR-PF groups (P<0.05). The excessive drinking, soft remnant pancreas, preoperative albumin, and intraoperative blood transfusion are risk factors affecting both PF and CR-PF incidence. More professional surgeons can effectively reduce the PF and CR-PF incidence. Patients with PF and CR-PF need more hospital costs and stages than that in NOPF and NOCR-PF groups. It is critical that surgeons know the risk factors related to PF and CR-PF so as to take corresponding therapeutic regimens for each patient
- …