Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

High concentration of vitamin E decreases thermosensation and thermotaxis learning and the underlying mechanisms in the nematode Caenorhabditis elegans.

α-tocopherol is a powerful liposoluble antioxidant and the most abundant isoform of vitamin E in the body. Under normal physiological conditions, adverse effects of relatively high concentration of vitamin E on organisms and the underlying mechanisms are still largely unclear. In the present study, we used the nematode Caenorhabditis elegans as an in vivo assay system to investigate the possible adverse effects of high concentration of vitamin E on thermosensation and thermotaxis learning and the underlying mechanisms. Our data show that treatment with 100-200 µg/mL of vitamin E did not noticeably influence both thermosensation and thermotaxis learning; however, treatment with 400 µg/mL of vitamin E altered both thermosensation and thermotaxis learning. The observed decrease in thermotaxis learning in 400 µg/mL of vitamin E treated nematodes might be partially due to the moderate but significant deficits in thermosensation, but not due to deficits in locomotion behavior or perception to food and starvation. Treatment with 400 µg/mL of vitamin E did not noticeably influence the morphology of GABAergic neurons, but significantly decreased fluorescent intensities of the cell bodies in AFD sensory neurons and AIY interneurons, required for thermosensation and thermotaxis learning control. Treatment with 400 µg/mL of vitamin E affected presynaptic function of neurons, but had no remarkable effects on postsynaptic function. Moreover, promotion of synaptic transmission by activating PKC-1 effectively retrieved deficits in both thermosensation and thermotaxis learning induced by 400 µg/mL of vitamin E. Therefore, relatively high concentrations of vitamin E administration may cause adverse effects on thermosensation and thermotaxis learning by inducing damage on the development of specific neurons and presynaptic function under normal physiological conditions in C. elegans

Safety and immunogenicity of a novel quadrivalent subunit influenza vaccine in animal models

Background: Compared with trivalent influenza vaccines, quadrivalent influenza vaccines are expected to provide wider protection against influenza B virus infections. We developed a novel quadrivalent subunit influenza vaccine which was distinct from the influenza vaccines available on the market in production process. In this research, we evaluated the safety and immunogenicity of the quadrivalent subunit influenza vaccine in animal models. Methods: In toxicity assessment, 40 SD rats were randomly assigned to be intramuscularly injected with 1.0 ml of the tested vaccine (33 μg/ml) or 0.9% sodium chloride solution. In irritation assessment, eight rabbits were randomly assigned to receive 0.5 ml of tested vaccine or phosphate buffer solution intramuscularly. Thirty-two guinea pigs were randomly assigned to be intramuscularly injected with high-dose tested vaccine (0.5 ml), low-dose tested vaccine (0.05 ml), ovalbumin, or 0.9% sodium chloride solution, respectively, for sensitization assessment. In immunogenicity assessment, 50 BALB/c mice were equally randomized to receive one dose of tested vaccine, two doses of tested vaccine with an interval of 14 days, 0.5 ml of trivalent subunit influenza vaccine, 0.5 ml of monovalent subunit influenza vaccine, or 0.5 ml of phosphate buffer solution. Orbital blood was collected before and 28 and 42 days after administration of the injections for detecting influenza antibody titers. Results: No abnormal toxicity and irritation in rats and rabbits showed in the gross autopsy and histopathological examinations. The results of sensitization in guinea pigs indicated that no obvious allergic symptoms observed in the high-dose and low-dose vaccine groups within 30 min after twice provocations, and the result of sensitization evaluation was negative. Vaccine induced significant immune responses in mice with 100% seroconversion rates at 28 and 42 days after the first dose. The geometric mean titers (GMTs) of hemagglutination inhibition (HI) antibodies at day 28 in one-dose quadri–vaccine and two-dose quadri–vaccine groups were comparable to those in the tri–vaccine or mono-vaccine groups for shared influenza strains. However, the GMTs of HI antibodies against H1N1 (P = 0.025) and BV (P = 0.049) at day 42 in one-dose quadri–vaccine group were significantly lower than those in the tri–vaccine or mono-vaccine groups. The GMTs of HI antibodies against H1N1, H3N1, BY, and BV at day 28 and day 42 were comparable between one-dose quadri–vaccine and two-dose quadri–vaccine groups. Conclusions: The quadrivalent subunit influenza vaccine was safe and immunogenic in animal models. One dose of the vaccine could elicit a satisfactory antibody response in mice

A New SCAE-MT Classification Model for Hyperspectral Remote Sensing Images

Hyperspectral remote sensing images (HRSI) have the characteristics of foreign objects with the same spectrum. As it is difficult to label samples manually, the hyperspectral remote sensing images are understood to be typical “small sample” datasets. Deep neural networks can effectively extract the deep features from the HRSI, but the classification accuracy mainly depends on the training label samples. Therefore, the stacked convolutional autoencoder network and transfer learning strategy are employed in order to design a new stacked convolutional autoencoder network model transfer (SCAE-MT) for the purposes of classifying the HRSI in this paper. In the proposed classification method, the stacked convolutional au-to-encoding network is employed in order to effectively extract the deep features from the HRSI. Then, the transfer learning strategy is applied to design a stacked convolutional autoencoder network model transfer under the small and limited training samples. The SCAE-MT model is used to propose a new HRSI classification method in order to solve the small samples of the HRSI. In this study, in order to prove the effectiveness of the proposed classification method, two HRSI datasets were chosen. In order to verify the effectiveness of the methods, the overall classification accuracy (OA) of the convolutional self-coding network classification method (CAE), the stack convolutional self-coding network classification method (SCAE), and the SCAE-MT method under 5%, 10%, and 15% training sets are calculated. When compared with the CAE and SCAE models in 5%, 10%, and 15% training datasets, the overall accuracy (OA) of the SCAE-MT method was improved by 2.71%, 3.33%, and 3.07% (on average), respectively. The SCAE-MT method is, thus, clearly superior to the other methods and also shows a good classification performance

miR-1224-3p Promotes Breast Cancer Cell Proliferation and Migration through PGM5-Mediated Aerobic Glycolysis

Metabolic reprogramming of aerobic glycolysis is a hallmark of cancer cells. Regulators of aerobic glycolysis have become targets for cancer diagnosis and therapy. However, the regulators of aerobic glycolysis in breast cancer development have not been well elucidated. Here, we show that the phosphoglucomutase (PGM) family member PGM5 promotes conversion of glucose-1-phosphate (G1P) into glucose-6-phosphate (G6P) and inhibits breast cancer cell proliferation and migration through regulating aerobic glycolysis. In breast cancer patients, PGM5 is significantly downregulated, and its low expression is a predictor of poor prognosis. MicroRNA-1224-3p (miR-1224-3p) inhibits the PGM5 level through directly targeting its 3’-untranslated region and suppresses PGM5-mediated breast cancer cell proliferation, migration, and glycolytic function. Moreover, the miR-1224-3p/PGM5 axis regulates the expression of cell cycle- and apoptosis-related genes and the markers of epithelial-mesenchymal transition (EMT), a process involved in migration and metastasis of cancer cells. Taken together, our results indicate that miR-1224-3p/PGM5 axis plays important roles in breast cancer cell proliferation, migration, and aerobic glycolysis and may be a potential target for breast cancer therapy

Peak Shaving and Frequency Regulation Coordinated Output Optimization Based on Improving Economy of Energy Storage

In this paper, a peak shaving and frequency regulation coordinated output strategy based on the existing energy storage is proposed to improve the economic problem of energy storage development and increase the economic benefits of energy storage in industrial parks. In the proposed strategy, the profit and cost models of peak shaving and frequency regulation are first established. Second, the benefits brought by the output of energy storage, degradation cost and operation and maintenance costs are considered to establish an economic optimization model, which is used to realize the division of peak shaving and frequency regulation capacity of energy storage based on peak shaving and frequency regulation output optimization. Finally, the intra-day model predictive control method is employed for rolling optimization. An intra-day peak shaving and frequency regulation coordinated output optimization strategy of energy storage is proposed. Through the example simulation, the experiment results show that the electricity cost of the whole day is reduced by 10.96% by using the coordinated output strategy of peak shaving and frequency regulation. The obtained further comparative analysis results and the life cycle economic analysis show that the profit brought by the proposed coordinated output optimization strategy is greater than that for separate peak shaving or frequency modulation of energy storage under the same capacity

Peak Shaving and Frequency Regulation Coordinated Output Optimization Based on Improving Economy of Energy Storage

In this paper, a peak shaving and frequency regulation coordinated output strategy based on the existing energy storage is proposed to improve the economic problem of energy storage development and increase the economic benefits of energy storage in industrial parks. In the proposed strategy, the profit and cost models of peak shaving and frequency regulation are first established. Second, the benefits brought by the output of energy storage, degradation cost and operation and maintenance costs are considered to establish an economic optimization model, which is used to realize the division of peak shaving and frequency regulation capacity of energy storage based on peak shaving and frequency regulation output optimization. Finally, the intra-day model predictive control method is employed for rolling optimization. An intra-day peak shaving and frequency regulation coordinated output optimization strategy of energy storage is proposed. Through the example simulation, the experiment results show that the electricity cost of the whole day is reduced by 10.96% by using the coordinated output strategy of peak shaving and frequency regulation. The obtained further comparative analysis results and the life cycle economic analysis show that the profit brought by the proposed coordinated output optimization strategy is greater than that for separate peak shaving or frequency modulation of energy storage under the same capacity

Effects of vitamin E treatment at different concentrations on thermotaxis and locomotion behaviors in <i>C. elegans</i>.

<p>(A) Effects of vitamin E treatment at different concentrations on thermotaxis behavior. In the thermotaxis assay system, movement to 25°C was scored as thermophilic (T); movement to 17°C was scored as cryophilic (C); movement across the thermal gradient (17°C/25°C) was scored as athermotactic (A); movement at 20°C was scored as isothermal tracking behavior (IT). (B) Effects of vitamin E treatment at different concentrations on body bends of nematodes inside and outside learning assay model. (C) Effects of vitamin E treatment at different concentrations on basic movements of the examined nematodes. (D) Effects of vitamin E treatment at different concentrations on basal and enhanced slowing responses of the examined nematodes. Data are expressed as mean ± SEM. **<i>p</i><0.01 vs. N2.</p

Effects of vitamin E treatment at different concentrations on synaptic neurotransmission in <i>C. elegans</i>.

<p>(A) Effects of vitamin E treatment on presynaptic function as evaluated by aldicarb resistance. (B) Effects of vitamin E treatment on postsynaptic function as evaluated by levamisole resistance. Data are expressed as mean ± SEM. **<i>p</i><0.01 vs. control.</p

Promotion of synaptic transmission effectively retrieved deficits in learning and thermotaxis behaviors in nematodes treated with 400 µg/mL of vitamin E.

<p>(A) Promotion of synaptic transmission effectively retrieved deficits in thermotaxis learning behavior in nematodes treated with 400 µg/mL of vitamin E as monitored by 25/20°C thermotaxis assay. (B) Promotion of synaptic transmission effectively retrieved deficits in thermotaxis learning behavior in nematodes treated with 400 µg/mL of vitamin E as monitored by 17/20°C thermotaxis assay. (C) Promotion of synaptic transmission effectively retrieved deficits in thermotaxis in nematodes treated with 400 µg/mL of vitamin E. In the thermotaxis assay system, movement to 25°C was scored as thermophilic (T); movement to 17°C was scored as cryophilic (C); movement across the thermal gradient (17°C/25°C) was scored as athermotactic (A); movement at 20°C was scored as isothermal tracking behavior (IT). Data are expressed as mean ± SEM. **<i>p</i><0.01 vs. N2.</p