Achieving Molecular Selectivity in Imaging Using Multiphoton Raman Spectroscopy Techniques

In the case of most optical imaging methods, contrast is generated either by physical properties of the sample (Differential Image Contrast, Phase Contrast), or by fluorescent labels that are localized to a particular protein or organelle. Standard Raman and infrared methods for obtaining images are based upon the intrinsic vibrational properties of molecules, and thus obviate the need for attached fluorophores. Unfortunately, they have significant limitations for live-cell imaging. However, an active Raman method, called Coherent Anti-Stokes Raman Scattering (CARS), is well suited for microscopy, and provides a new means for imaging specific molecules. Vibrational imaging techniques, such as CARS, avoid problems associated with photobleaching and photo-induced toxicity often associated with the use of fluorescent labels with live cells. Because the laser configuration needed to implement CARS technology is similar to that used in other multiphoton microscopy methods, such as two-photon fluorescence and harmonic generation, it is possible to combine imaging modalities, thus generating simultaneous CARS and fluorescence images. A particularly powerful aspect of CARS microscopy is its ability to selectively image deuterated compounds, thus allowing the visualization of molecules, such as lipids, that are chemically indistinguishable from the native species.     

Effect of dietary fat or starch supply during gestation and/or lactation on the performance of sows, piglets' survival and on the performance of progeny after weaning

Two trials were carried out to compare the effects of fat or starch inclusion in sow's diet on sow and litter performance. In each trial, sows were assigned to one of two treatments. In trial 1, the sows were fed diets containing either soybean oil (5%, treatment GL5) or cornstarch (11.3%, GL0) from day 35 of gestation to weaning. Daily net energy and nutrient allowance were equalised during gestation. In trial 2, the same treatments were applied only after farrowing (treatments L5 and L0, respectively). Within each trial, a batch of piglets was studied until slaughter. In trial 1, adipose cell development and total lipid content were determined on some pigs at weaning (n = 6/treatment) and at slaughter in dorsal subcutaneous adipose tissue (n = 13/group at least) and in muscle (n = 46/group at least). Piglets' birth weight was not affected by treatment in trial 1. Survival rates at birth and after 24 h of life were higher in treatment GL5 (4.0% v. 7.5% stillborn piglets in GL0 treatment, P < 0.05; 8.7% v. 12.6% of piglets alive at 24 h of age died in treatment GL0, P = 0.06). Subsequently, overall survival rate until weaning was higher in treatment GL5 (81.4% v. 75.7% of total born piglets, P = 0.03), but litter size at weaning was not significantly affected (11.3). Litter growth rate before weaning was increased when a fat-enriched diet was provided during gestation and lactation (+140 g/day per litter; P < 0.01) and to a lower extent when provided only after farrowing (+90 g/day; P < 0.05). Energy supply through fat did not decrease the mobilisation of the sow's body reserve and backfat thickness loss was even higher with treatment GL5 (P < 0.05). After weaning, pigs' average daily gain, feed : gain ratio and carcass lean content were not affected by the energy source supplied before and/or after farrowing. At weaning, the number of adipose cells in the dorsal subcutaneous adipose tissue and in the Longissimus dorsi muscle was higher in the GL5 pigs. Muscle lipid content at weaning did not differ between treatments, but it was higher at slaughter, around 110 kg, in the GL5 pigs (3.46% v. 2.58%, P < 0.001).     

钼、硼对大豆叶片膜脂过氧化及体内保护系统的影响

The study deals with the changes of membrane peroxidation and endogenous protective system with different supplementation of molybdenum (Mo) and/or boron (B) concentration in soybean (Glycine max L.) leaves at three developmental stages (5-trifoliate stage, initiation of flowering, and peak podsetting stage) in three pot-grown soybean varieties (“Zhechun No.3”, “Zhechun No.2”, “3811”). The control plants under low Mo and low B exhibited an increasing of membrane permeability (MP), malondialdehyde (MDA) and proline (Pro) contents, polyphenol oxidase (PPO) and ascorbate oxidase (AO) activities and a decrease of ascorbate (AsA) contents, superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (AP) and catalase (CAT) activities. Application of Mo or B alone raised the ability of anti-oxidant of soybean leaves. The results indicated that the anti-oxidant enzymes (including SOD, POD, CAT and AP) related closely to anti-oxidant compounds (including AsA and Pro). There was some difference between the effects of Mo and B on the anti-oxidant, and a synergetic effect was observed between Mo and B. Some genetic variation in the responses to Mo and B was found among the three soybean varieties which was related to the activities of the total anti-oxidant systems.     

茵陈五苓散联合利拉鲁肽对肥胖型2型糖尿病患者糖脂代谢、胰岛素敏感性和氧化应激的影响

摘要 目的：探讨茵陈五苓散联合利拉鲁肽对肥胖型2型糖尿病（T2DM）患者糖脂代谢、胰岛素敏感性和氧化应激的影响。方法：选取2021年12月~2022年12月期间广州中医药大学附属佛山中医院收治的160例痰湿内蕴型肥胖T2DM患者。根据随机数字表法将患者分为对照组（利拉鲁肽治疗,80例）和研究组（茵陈五苓散联合利拉鲁肽治疗,80例）。对比两组疗效、糖脂代谢指标、肥胖相关指标、胰岛素敏感性、氧化应激和不良反应发生情况。结果：与对照组相比,研究组的临床总有效率更高（P<0.05）。研究组治疗后体质量指数（BMI）、空腹血糖（FBG）、腰臀比（WHR）、餐后2 h血糖（2hPG）、丙二醛（MDA）、糖化血红蛋白（HbAlc）、稳态模型胰岛素抵抗指数（HOMA-IR）、总胆固醇（TC）、黄嘌呤氧化酶（XO）、甘油三酯（TG）、低密度脂蛋白胆固醇（LDL-C）较对照组低（P<0.05）。治疗后研究组稳态模型胰岛β细胞功能指数（HOMA-β）、高密度脂蛋白胆固醇（HDL-C）、超氧化物歧化酶（SOD）高于对照组（P<0.05）。两组不良反应发生率组间对比未见差异（P>0.05）。结论：茵陈五苓散联合利拉鲁肽治疗肥胖型T2DM患者疗效确切,可调节糖脂代谢水平,降低胰岛素敏感性,减轻氧化应激,且具有一定安全性,值得临床借鉴应用。     

Plasma lipid peroxidation and erythrocyte antioxidants status in workers exposed to nickel

The objectives were to investigate the plasma lipid peroxidation and erythrocyte antioxidants status in workers exposed to nickel. The study groups comprised 69 nickel plating workers and 50 office workers residing in the same city, but away from the place of work of the study group subjects, considered as control group. Urinary nickel concentration was determined by graphite furnace atomic absorption spectrophotometry. The plasma lipid peroxidation and erythrocyte antioxidants were measured by spectrophotmetric methods. The plasma lipid peroxidation level was significantly increased in nickel-platers and their helpers as compared with controls. Erythrocyte antioxidants were significantly decreased in the nickel-platers compared with the controls. The level of plasma lipid peroxidation was positively and erythrocyte antioxidants were negatively and significantly correlated with the urine nickel levels. Multiple regression analysis assessed the oxidative stress associated with nickel and other potential confounding factors such as body mass index, the consumption of green vegetables, coffee, tea, smoking and alcohol consumption. Analysis showed that the lifestyle confounding factors: the consumption of green vegetables, smoking and alcohol, were not significantly associated with oxidative stress. The exposure to nickel, body mass index and coffee consumption were significantly associated with oxidative stress. The results show that the increased plasma lipid peroxidation and decreased erythrocyte antioxidants levels observed in nickel-exposed workers could be used as biomarkers of oxidative stress.     

ARF-GTPase activating protein mediates auxin influx carrier AUX1 early endosome trafficking to regulate auxin dependent plant development

Polar auxin transport (PAT) plays a critical role in the regulation of plant growth and development. Auxin influx carrier AUX1 is predominantly localized to the upper side of specific root cells in Arabidopsis. Overexpression of OsAGAP, an ARF-GTPase activating protein in rice, could induce the accumulation of AUX1. But the mechanism is poorly known. Here we reported that over-expression of ARF-GAP could reduce the thickness and bundling of microfilament (MF) which possibly could greatly interfere with the endocytosis of AUX1 early endosome; but not the exocytosis of AUX1 recycling endosome. Therefore, AFR-GAP over-expression suppressed-MF bundling is likely involved in regulating endocytosis of Auxin influx carrier AUX1 and in mediating auxin dependent plant development.         

Changes in the lipid and fatty acid composition of hemolymph and ovaries during the reproductive cycle of Labidura riparia

Lipid metabolism was investigated during the reproductive cycle of Labidura riparia (Pallas). The lipid classes and their constitutive fatty acids present in hemolymph and ovaries were measured using thin‐layer chromatography and gas‐liquid chromatography. In the hemolymph, total lipids increase steadily from the previtellogenic period to vitellogenic arrest. These lipids are predominantly diacylglycerols and phospholipids. In the ovaries, total lipids increase during vitellogenesis then decrease during the vitellogenesis arrest period. The major lipids are triacylglycerols, followed by phospholipids. In both hemolymph and ovaries, all lipid classes contained variable proportions of seven main fatty acids: the saturated fatty acids myristic acid (14:0), palmetic acid (16:0), and stearic acid (18:0); the monounsaturated fatty acids palmitoleic acid (16:1) and oleic acid (18:1); and the polyunsaturated fatty acids linoleic acid (18:2) and linolenic acid (18:3). Unsaturated fatty acids predominate throughout the reproductive cycle. The percentage compositions of total and triacylglycerol fatty acids do not change markedly during the reproductive cycle in hemolymph nor in ovaries, with 18:2, 18:1 and 16:0 fatty acids being the major components. However, for diacylglycerols and phospholipids, the proportions of fatty acids vary systematically. For phospholipids during the vitellogenesis period, 18:2 increases considerably whereas other fatty acids decrease; for diacylglycerols, these fatty acids vary in the reverse way.     

Lipids and lipid metabolism in the brown alga, Fucus serratus

The lipids of the brown alga Fucus serratus were isolated, identified and quantified. The major acyl lipids were the three glycosylglycerides, diacylgalactosylglycerol, diacyldigalactosylglycerol and diacylsulphoquinovosylglycerol. These represent over 70% of the total acyl lipids. The fatty acid compositions of the major lipids were examined and most showed rather distinctive fatty acid contents. For example, diacylgalactosylglycerol was enriched in n-3 polyunsaturated fatty acids while phosphatidylcholine and phosphatidylethanolamine had very high levels of arachidonate. Phosphatidylglycerol contained the unusual trans-Δ3-hexadecenoic acid. The labelling of lipids and fatty acids from [¹⁴C]acetate was examined and the distribution of label between individual components as a function of the incubation period and in algae collected at different times of the year is reported. Algae collected in the winter incorporated much more radioactivity into non-esterified fatty acids when compared to algae collected in the summer. All algae could label myristate, palmitate, stearate and oleate at high rates. Longer incubation times allowed the labelling of polyunsaturated fatty acids such as linoleic acid.     

Modeling squid axon Na+ channel by a nucleation and growth kinetic mechanism

A kinetic model accounting for all salient features of the Na⁺ channel of the squid giant axon is provided. The model furnishes explanations for the Cole-Moore-like effect, the rising phase of the ON gating current and the slow ‘intermediate component’ of its decaying phase, as well as the gating charge immobilization. Experimental ON ionic currents are semi-quantitatively simulated by the use of only three free parameters, upon assuming that the Na⁺ channel opening proceeds along with the stepwise aggregation of its four domains, while they are moving their gating charge outward under depolarizing conditions. The inactivation phase of the ON ionic current is interpreted by a progressive electrostatic attraction between the positively charged ‘hinged lid’ containing the hydrophobic IFM triad and its receptor inside the channel pore, as the stepwise outward movement of the S4 segments of the Na⁺ channel progressively increases the negative charge attracting the triad to its receptor. The Na⁺ channel closing is assumed to proceed by repolarization-induced disaggregation of its domains, accompanied by inward movement of their gating charge. The phenomenon of ‘gating charge immobilization’ can be explained by assuming that gradual structural changes of the receptor over the time course of depolarization strengthen the interaction between the IFM triad and its receptor, causing a slow release of the gating charge during the subsequent repolarization.