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Previous nutritional studies have shown that insulin regulation is different between DT and A strains of gibel carp. As leptin plays a pivotal role in the effects of insulin, we hypothesized that leptin regulation of glucose and lipid metabolism would differ between the two strains. To test our hypothesis, recombinant human leptin was injected into two strains. The results showed that leptin activated PI3K-AKT, AMPK-ACC, and JAK2-STAT signaling pathways in both strains. Hypoglycemia induced by leptin might be due to higher glucose uptake by the liver and muscles together with enhanced glycolytic potential and reduced gluconeogenic potential. Decreased lipogenesis and up-regulated fatty acid oxidation were induced by leptin. In terms of genotype, the PI3K-AKT signaling pathway was more strongly activated by leptin in the muscle tissue of the A strain, as reflected by the heightened phosphorylation of AKT. Furthermore, glycogen content, glycolytic enzyme activity, and gluconeogenic capability were higher in the A strain than the DT strain. Strain A had higher levels of fatty acid synthesis and lipolytic capacity in the liver than the DT strain, but the opposite was true in white muscle. Regarding leptin-genotype interactions, the DT strain displayed stronger regulation of glucose metabolism in the liver by leptin as compared to the A strain. Moreover, a more active JAK2-STAT signaling pathway accompanied by enhanced inhibition of fatty acid synthesis by leptin was observed in the DT strain. Overall, the regulation of glucose and lipid metabolism by leptin differed between the two strains, as expected.
A novel ionic liquid/α-ZrP (C16MIM/α-ZrP) lamellar nanocomposite was fabricated via the electrostatic self-assembly deposition technique by using exfoliated α-ZrP nanosheets and guest molecules (1-hexadecyl-3-methylimidazolium bromide) as building blocks under mild conditions. C16MIM/α-ZrP nanocomposite was characterized by various analytical techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier transform infrared spectroscopy, and synchronous thermal analyzer. The net interlayer spacing of α-ZrP determined by XRD confirmed that the C16MIM cations formed a monolayer arrangement between the α-ZrP nanosheets. The morphology and microstructure of C16MIM/α-ZrP composite were observed using SEM and TEM. The C16MIM/α-ZrP modified glass carbon electrode exhibited excellent electrocatalytic activity toward the oxidation of nitrite in weak base media. The results obtained with differential pulse voltammetry demonstrated that the C16MIM/α-ZrP hybrid detected nitrite linearly in the concentration range from 7.3 μM to 1.25 mM with the detection limit of 1.26 μM (S/N = 3). Additionally, the prepared sensor showed outstanding reproducibility, high stability, and anti-interference capability.
Since the outbreak of 2019 novel coronavirus infection (2019-nCoV) in Wuhan City, China, pediatric cases have gradually increase. It is very important to prevent cross-infection in pediatric fever clinics, how identify children with fever in pediatric fever clinics, and strengthen the management of pediatric fever clinics. According to prevention and control programs, we propose the guidance on the management of pediatric fever clinics during the novel coronavirus pneumonia epidemic period, which outlines in detail optimizes processes, prevents cross-infection, health protection and disinfection of medical staff. The present consideration statement summarizes current strategies on pre-diagnosis, triage, diagnosis, treatment, and prevention of 2019-nCoV infection, which provide practical suggestions on strengthening the management of pediatric fever clinics during the novel coronavirus pneumonia epidemic period.
This Research Reflection short review presents an overview of the effects of heat stress on dairy cattle udder health and discusses existing heat stress mitigation strategies for a better understanding and identification of appropriate abatement plans for future stress management. Due to high ambient temperatures with high relative humidity in summer, dairy cows respond by changes of physical, biochemical and biological pathways to neutralize heat stress resulting in decreased production performance and poorer immunity resulting in an increased incidence of intramammary infections (IMI) and a higher somatic cell count (SCC). In vitro studies on bovine polymorphonuclear cells (PMN) suggested that heat stress reduces the phagocytosis capacity and oxidative burst of PMN and alters the expression of apoptotic genes and miRNA which, together with having a negative effect on the immune system, may explain the increased susceptibility to IMI. Although there are limited data regarding the incidence rate of clinical mastitis in many countries or regions, knowledge of SCC at the cow or bulk tank level helps encourage farmers to improve herd health and to develop strategies for infection prevention and cure. Therefore, more research into bulk tank SCC and clinical mastitis rates is needed to explain the effect of heat stress on dairy cow udder health and functions that could be influenced by abatement plans.
Coated copper sulphate (CCS) could be used as a Cu supplement in cows. To investigate the influences of copper sulphate (CS) and CCS on milk performance, nutrient digestion and rumen fermentation, fifty Holstein dairy cows were arranged in a randomised block design to five groups: control, CS addition (7·5 mg Cu/kg DM from CS) or CCS addition (5, 7·5 and 10 mg Cu/kg DM from CCS, respectively). When comparing Cu source at equal inclusion rates (7·5 mg/kg DM), cows receiving CCS addition had higher yields of fat-corrected milk, milk fat and protein; digestibility of DM, organic matter (OM) and neutral-detergent fibre (NDF); ruminal total volatile fatty acid (VFA) concentration; activities of carboxymethyl cellulase, cellobiase, pectinase and α-amylase; populations of Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes; and liver Cu content than cows receiving CS addition. Increasing CCS addition, DM intake was unchanged, yields of milk, milk fat and protein; feed efficiency; digestibility of DM, OM, NDF and acid-detergent fibre; ruminal total VFA concentration; acetate:propionate ratio; activity of cellulolytic enzyme; populations of total bacteria, protozoa and dominant cellulolytic bacteria; and concentrations of Cu in serum and liver increased linearly, but ruminal propionate percentage, ammonia-N concentration, α-amylase activity and populations of Prevotella ruminicola and Ruminobacter amylophilus decreased linearly. The results indicated that supplement of CS could be substituted with CCS and addition of CCS improved milk performance and nutrient digestion in dairy cows.
The Antarctic subglacial drilling rig (ASDR) is designed to recover 105 mm-diameter ice cores up to 1400 m depth and 41.5 mm-diameter bedrock cores up to 2 m in length. In order to ensure safe and convenient drilling, drilling auxiliaries are designed to support fieldwork and servicing. These auxiliaries are subdivided into several systems for power supply, drill tripping in the borehole, ice core and chip processing, and drill servicing and maintenance. The required equipment also includes two generators, a drilling winch with a cable, logging winch with a cable, control desk, pipe handler with a fixed clamp, chip chamber vibrator, centrifuge, emergency devices and fitting and electrical tools. Additionally, several environmental protective measures such as a new liquid-tight casing with a thermal casing shoe and a bailing device for recovering drilling fluid from the borehole were designed. Most of the auxiliaries were tested during the summer of 2018–2019 near Zhongshan Station, East Antarctica while drilling to the bedrock to a depth of 198 m.
A new, modified version of the cable-suspended Ice and Bedrock Electromechanical Drill (IBED) was designed for drilling in firn, ice, debris-rich ice and rock. The upper part of the drill is almost the same for all drill variants and comprises four sections: cable termination, a slip-ring section, an antitorque system and an electronic pressure chamber. The lower part of the IBED comprises an auger core barrel, reamers, a core barrel for ice/debris-ice drilling and a conventional geological single-tube core barrel or custom-made double-tube core barrel. First, the short and full-scale field versions of the IBED were tested at an outdoor testing stand and a testing facility with a 12.5 m-deep ice well. Then, in the 2018–2019 summer season, the IBED was tested in the field at a site ~12 km south of Zhongshan Station, East Antarctica, and a ~6 cm bedrock core was recovered from a 198 m-deep borehole. A total of 18 d was required to penetrate the ice sheet. The retrieved core samples of blue ice, basal ice and bedrock provided valuable information regarding the Earth's paleo-environment.
The surface topology of biomaterial has a definite effect on the growth behavior of nerve cells for peripheral nerve regeneration. In this study, the silk fibroin (SF) film with different anisotropic microgroove/ridge was constructed by micropatterning technology. The effects of topologies width on the directional growth of dorsal root ganglion (DRG) neurons were evaluated. The results showed that the topological structure of the SF film with higher SF concentration was more clear and complete. The microtopography of the SF film with a concentration of 15% and a groove width of around 30 μm could effectively guide the directional growth of the nerve fibers of DRG. And nerve fibers could obviously form nerve fiber bundles which may have a certain pavement effect on the recovery of nerve function. The study indicated that the SF film with a specific width of the topological structure may have potential applications in the field of directional nerve regeneration.
We investigate the phased evolution and variation of the South Asian monsoon and resulting weathering intensity and physical erosion in the Himalaya–Karakoram Mountains since late Pliocene time (c. 3.4 Ma) using a comprehensive approach. Neodymium and strontium isotopic compositions and single-grain zircon U–Pb age spectra reveal the sources of the deposits in the east Arabian Sea, and show a combination of sources from the Himalaya and the Karakoram–Kohistan–Ladakh Mountains, with sediments from the Indian Peninsula such as the Deccan Traps or Craton. We interpret shifts in the sediment sources to have been forced by sea-level changes that correlate with South Asian monsoon rainfall variation since late Pliocene time. We collected 908 samples from the International Ocean Discovery Program Hole U1456A, which was drilled in the east Arabian Sea. Time series of hematite content and grain size of the sediments were examined downcore. We found South Asian monsoon precipitation and weathering intensity experienced three phases from late Pliocene time. Lower monsoon precipitation, with a lower variability and strong weathering intensity, occurred during 3.4–2.4 Ma; an increased and more variable South Asian monsoon rainfall, along with strengthened but fluctuating weathering intensity, occurred at 1.8–1.1 Ma; and a reduced rainfall with lower South Asian monsoon precipitation variability and moderate weathering intensity marked the period 1.1–0.1 Ma. Maximum entropy spectral analysis and wavelet transform show that there were orbital-dominated cycles of periods c. 100 and c. 41 ka in these proxy-based time series. We propose that the monsoon, sea level, global temperature and insolation together forced the weathering and erosion in SW Asia.
The aim of this study was to reveal the possible mechanisms involved in apoptosis induced by single prolonged stress (SPS) in hippocampus of post-traumatic stress disorder (PTSD) rats.
SPS is one of the animal models proposed for PTSD. Wistar rats were killed at 1, 4, 7, 14 and 28days after exposure to SPS. Expression of caspase-9, caspase-3, cytochrome c, Bcl-2 and Bax was detected by immunohistochemistry, immunofluorescence, western blotting and electron microscopy. Apoptotic cells were assessed by TUNEL method.
Our results showed apoptotic cells were significantly increased in hippocampus of SPS rats, accompanied by release of cytochrome c from the mitochondria into the cytosol, increase of caspase-9 and caspase-3 expression and decrease of the Bcl-2 / Bax ratio.
The results indicate that SPS induced apoptosis in hippocampus of PTSD rats, and the mitochondrial pathway was involved in the process of SPS induced apoptosis. *National Natural Science Foundation of China
To observe the changes of glucocorticoid receptors(GR) in the nucleus raphes magnus (NRM)neurons of PTSD-like rats.
25 male Wistar rats were randomly divided into PTSD model 1d, 4d, 7d, 14d groups and a normal group with 5 rats in each group. Rats in model groups were treated with SPS procedure to reproduce PTSD model.The changes of expression of GR in NRM of rats were detected by immunohistochemistry and PCR in each group, and image analysis and statistical analysis were performed in each group.
GR was distributed in the nucleus of neurons. The expression of GR was sharply decreased on 1d, but gradually increased on 4d and 7d, then decreased on 14d. All of 4d, 7d, 14d are higher than the normal (P < 0.05).
The lasting dysfunction of GR in the nucleus raphes magnus (NRM) may play an important role in post-traumatic stress disorder rats.
To detect molecular chaperone calreticulin(CRT) expression on the hippocampus in the rat model of post-traumatic stress disorder(PTSD), and discuss the regulation of CRT on Ca2+ in hippocampus of PTSD rats, further provide the experiment basis for pathogenesis of memory anomaly in PTSD rats.
The single-prolonged stress(SPS) is one of the animal models was used to set up the rat PTSD models. Male Wistar rats were randomly divided into 1, 4, 7 days groups after exposure to SPS and a normal control group. The expression of CRT was detected by using immunohistochemistry, Western blotting and RT-PCR. The intracellular free calcium was examined by fluorescence spectrophotometer.
The expression of CRT in the hippocampus obviously increased after SPS stimulation, and reached the peak at SPS 4d. The intracellular free calcium level in the hippocampus obviously increased, and reached the peak at SPS 1d, then gradually decreased.
PTSD caused endoplasmic reticulum stress(ERS), calcium overload, up-regulated expression of CRT, activation of unfolded protein response(UPR), which maybe result in cell apoptosis and maybe the pathogenesis basis on memory anomaly in PTSD rats.
To gain more comprehensive understanding of metabolic syndrome (Mets) among in general Chinese population.
Cross-sectional study. Mets was defined by three widely accepted definitions including modified Adults Treatment Panel (ATP) III criteria, International Diabetes Federation (IDF) criteria and harmonized definition. Risk factors were evaluated by using multivariate logistic regression.
Nineteen rural villages in northeast China.
The survey was conducted in September 2017 and May 2018 on 10 926 individuals.
According to modified ATP III criteria, IDF criteria and harmonised definition, the overall prevalence of Mets was 41·3 % (95 % CI 40·3, 42·2), 34·2 % (95 % CI 33·2, 35·1) and 44·1 % (95 % CI 43·1, 45·1), respectively. Females had a higher prevalence, and elevated blood pressure was the most frequent. Age, female sex, non-peasant worker, higher BMI and lower-annual income were independent risk factors of Mets in all three definitions (all ps < 0·05). Based on modified ATP III criteria and harmonised definition, heavy drinking was positively correlated with Mets. In contrast, former drinking was inversely associated with Mets.
Mets is highly prevalent in rural areas of northeast China. Its independent risk factors include higher age, female sex, non-peasantry worker, higher BMI and lower-annual income. Modified ATP III criteria and harmonised definition may be superior definitions of Mets.
Tuberculosis (TB) is generally considered a disease that principally afflicts the low-income segments of a population. In the Nanshan District of Shenzhen, China, with the economic transformation and a new Headquarters Economy (HE) emerging, there are now more cases in office workers than in manufacturing workers. To illustrate this trend, we describe a small TB outbreak in an office building located in the centre of the rapidly growing HE district. Two active pulmonary tuberculosis cases were found in workers who shared an office, and whole genome sequencing showed that the genetic distance between the strains of the two cases was just one single nucleotide polymorphism, consistent with intra-office transmission. Investigation of 30 other workers in the same or adjacent offices with interviews, interferon-gamma release assays (IGRAs) and chest X-rays, identified one new TB case and latent tuberculosis infection (LTBI) in 40.0% (12/30) of the contacts. The offices were under-ventilated. None of the IGRA positive, asymptomatic contacts agreed to receive treatment for LTBI, presumably due to TB stigma, and over the next 2 years 69.0% (20/29) of the contacts were lost to follow-up. Treatment for LTBI and stigma of TB remain challenges here. Office workers in the HE of rapidly economic developing areas should be targeted with increased vigilance by TB control programmes.
Materials with crystal structures containing tetrahedral motifs are preferable for optoelectronic applications because they often have direct band gaps and low electron effective masses. However, crystal structures of manganese chalcogenides typically contain octahedral motifs, such as in rock salt (RS) MnS and MnSe materials. Here, we experimentally show that MnS1−xSex alloys with tetrahedrally bonded wurtzite (WZ) structure can form between MnSe and MnS parent compounds with octahedral RS structures, at S-rich compositions (x < 0.4) and low synthesis temperatures (∼300 °C). The calculated mixing enthalpies of MnS1−xSex alloys in RS and WZ structures cannot explain this experimental observation, so we hypothesize that WZ stabilization may be related to smaller structure density and lower surface energy compared with RS. The resulting WZ MnS1−xSex alloys have 3.0–3.2 eV optical absorption onset and lower electrical conductivity (<0.0001 S/cm) than the parent RS compounds. These experimental measurement results are consistent with computationally predicted band gaps and effective masses.