Cells receive growth and survival stimuli through their attachment to an extracellular matrix (ECM). Overcoming the addiction to ECM-induced signals is required for anchorage-independent growth, a ...property of most malignant cells. Detachment from ECM is associated with enhanced production of reactive oxygen species (ROS) owing to altered glucose metabolism. Here we identify an unconventional pathway that supports redox homeostasis and growth during adaptation to anchorage independence. We observed that detachment from monolayer culture and growth as anchorage-independent tumour spheroids was accompanied by changes in both glucose and glutamine metabolism. Specifically, oxidation of both nutrients was suppressed in spheroids, whereas reductive formation of citrate from glutamine was enhanced. Reductive glutamine metabolism was highly dependent on cytosolic isocitrate dehydrogenase-1 (IDH1), because the activity was suppressed in cells homozygous null for IDH1 or treated with an IDH1 inhibitor. This activity occurred in absence of hypoxia, a well-known inducer of reductive metabolism. Rather, IDH1 mitigated mitochondrial ROS in spheroids, and suppressing IDH1 reduced spheroid growth through a mechanism requiring mitochondrial ROS. Isotope tracing revealed that in spheroids, isocitrate/citrate produced reductively in the cytosol could enter the mitochondria and participate in oxidative metabolism, including oxidation by IDH2. This generates NADPH in the mitochondria, enabling cells to mitigate mitochondrial ROS and maximize growth. Neither IDH1 nor IDH2 was necessary for monolayer growth, but deleting either one enhanced mitochondrial ROS and reduced spheroid size, as did deletion of the mitochondrial citrate transporter protein. Together, the data indicate that adaptation to anchorage independence requires a fundamental change in citrate metabolism, initiated by IDH1-dependent reductive carboxylation and culminating in suppression of mitochondrial ROS.
Activated beige adipocytes have therapeutic potential due to their ability to improve glucose and lipid homeostasis. To date, the origin of beige adipocytes remains enigmatic. Whether beige cells ...arise through de novo differentiation from resident precursors or through reprogramming of mature white adipocytes has been a topic of intense discussion. Here, we offer our perspective on the natural origin of beige adipocytes in mice. In particular, we revisit recent lineage-tracing studies that shed light on this issue and offer new insight into how environmental housing temperatures early in life influence the mode of beige adipocyte biogenesis upon cold exposure later in life. We suggest a unified model in which beige adipocytes (UCP1
multilocular cells) in rodents initially arise predominantly from progenitors (i.e., de novo beige adipogenesis) upon the first exposure to cold temperatures and then interconvert between "dormant beige" and "active beige" phenotypes (i.e., beige cell activation) upon subsequent changes in environmental temperature. Importantly, we highlight experimental considerations needed to visualize de novo adipogenesis versus beige cell activation in mice. A precise understanding of the cellular origins of beige adipocytes emanating in response to physiological and pharmacological stimuli may better inform therapeutic strategies to recruit beige adipocytes in vivo.
•Holographic frames encryption via new CA pixel-permutation encoding algorithm.•Huge library of cryptographic keys derived from a family of CA.•Property of floating-point-free of CA provides error ...free encoding.
The security of video data is necessary in network security transmission hence cryptography is technique to make video data secure and unreadable to unauthorized users. In this paper, we propose a holographic frames encryption technique based on the cellular automata (CA) pixel-permutation encoding algorithm. The concise pixel-permutation algorithm is used to address the drawbacks of the traditional CA encoding methods. The effectiveness of the proposed video encoding method is demonstrated by simulation examples.
► Find a new way to improve the antioxidant of whey protein isolate. ► Whey protein isolate (WPI) and seven types of sugars formed MRPs. ► The MRPs exhibited antioxidant activities. ► The MRPs may be ...used as natural antioxidants in food products. ► Study on the changes of the space and molecular of WPI after Maillard reaction.
The objective of this study was to determine antioxidant activities of water-soluble MRPs (Maillard reaction products) from the reactions between whey protein isolate (WPI) and xylose (X), glucose (G), fructose (F), lactose (L), maltose (M) and sucrose (S) at different initial pH values (3, 4, 5, 6, 7, 8 and 9). MRPs derived from the WPI-X system with increasing of pH rendered the highest browning, reducing power and DPPH radical-scavenging activity. SDS–PAGE analyses indicated formation of cross-linked proteins of large molecular mass produced from WPI-X systems. Results of FT-IR analysis indicated that the amide I, II and III bands of WPI from the WPI-X and WPI-G systems were changed by the Maillard reaction. CD spectroscopy showed that β-sheet, β-turns and random coil were increased while the α-helix was decreased after the WPI-G and WPI-X system aqueous solutions were heated. In conclusion, MRPs obtained from the WPI-X system had high antioxidant activity.
In this paper, we demonstrate a variable aperture with graded attenuation combined with adjustable focal length lens actuated by hydraulic control. Two cylindrical chambers and a middle substrate are ...stacked to form the device body. An elastic film is fabricated in the middle substrate like a sandwich. In the initial state, the dyed liquid is fully covered on the elastic film. The variable aperture shows the state of the maximum optical attenuation. When the bottom chamber is injected with liquid, the elastic film can form a convex surface. The dyed liquid will be pushed to the side wall of the chamber by the raised elastic film and the optical attenuation can be varied by changing the volume of the injected liquid. The proposed device can achieve both the variable attenuator function and the variable-focus lens function. The experiments show that the variable aperture can obtain dynamic attenuation ranges from 33.01 dB to 0.71 dB, and the zoom liquid lens can reach 2.9☓magnifying power. The device can be applied in imaging systems and fiber-optic communications.
An outbreak of coronavirus disease 2019 (COVID-19) is a public health emergency of international concern and poses a big challenge to medical staff and general public. The aim is to investigate ...psychological impact of COVID-19 epidemic on medical staff in different working posts in China, and to explore the correlation between psychological disorder and the exposure to COVID-19.
A multicenter WeChat-based online survey was conducted among medical staff in China between 26 February and 3 March 2020. Medical staff deployed to Hubei province from other provinces and medical staffs in different posts outside Hubei were selected to represent diverse exposure intensities to the threat of COVID-19. Anxiety, depression, sleep quality, stress and resilience were evaluated using scales including GAD-7, PHQ-9, PSQI, PSS-14, and CD-RISC-10. Latent class analysis was performed to identify potential staff requiring psychological support.
A total of 274 respondents were included, who serving at 4 posts as follows, staff backing Hubei province, isolation wards outside Hubei, fever clinic and infectious disease department, and other departments outside Hubei. The total scores of anxiety, depression, sleep quality and stress were statistically different among groups, meanwhile an increasing tendency of anxiety, depression and sleep quality scores with increasing risk of exposure to COVID-19 was found (p < 0.05). Subsequent post-hoc analysis indicated that the staff backing Hubei had higher scores of anxiety, depression, sleep quality and perceived stress (adjusted p < 0.05). The combined prevalence of anxiety, depression and insomnia of staff backing Hubei reached as high as 38%. Four-class latent class analysis showed 3 categories of population (69.4%) may need psychological support.
High prevalence of anxiety, depression and insomnia exist in medical staff related to COVID-19. The higher the probability and intensity of exposure to COVID-19 patients, the greater the risk that medical staff will suffer from mental disorders, suggesting continuous and proper psychiatric intervention are needed.
Regulations currently in force enable to claim that the lead content in perovskite solar cells is low enough to be safe, or no more dangerous, than other electronics also containing lead. However, ...the actual environmental impact of lead from perovskite is unknown. Here we show that the lead from perovskite leaking into the ground can enter plants, and consequently the food cycle, ten times more effectively than other lead contaminants already present as the result of the human activities. We further demonstrate that replacing lead with tin represents an environmentally-safer option. Our data suggest that we need to treat the lead from perovskite with exceptional care. In particular, we point out that the safety level for lead content in perovskite-based needs to be lower than other lead-containing electronics. We encourage replacing lead completely with more inert metals to deliver safe perovskite technologies.
Brown adipose tissue (BAT), as the main site of adaptive thermogenesis, exerts beneficial metabolic effects on obesity and insulin resistance. BAT has been previously assumed to contain a homogeneous ...population of brown adipocytes. Utilizing multiple mouse models capable of genetically labeling different cellular populations, as well as single-cell RNA sequencing and 3D tissue profiling, we discovered a brown adipocyte subpopulation with low thermogenic activity coexisting with the classical high-thermogenic brown adipocytes within the BAT. Compared with the high-thermogenic brown adipocytes, these low-thermogenic brown adipocytes had substantially lower Ucp1 and Adipoq expression, larger lipid droplets, and lower mitochondrial content. Functional analyses showed that, unlike the high-thermogenic brown adipocytes, the low-thermogenic brown adipocytes have markedly lower basal mitochondrial respiration, and they are specialized in fatty acid uptake. Upon changes in environmental temperature, the 2 brown adipocyte subpopulations underwent dynamic interconversions. Cold exposure converted low-thermogenic brown adipocytes into high-thermogenic cells. A thermoneutral environment had the opposite effect. The recruitment of high-thermogenic brown adipocytes by cold stimulation is not affected by high-fat diet feeding, but it does substantially decline with age. Our results revealed a high degree of functional heterogeneity of brown adipocytes.
In this paper, we propose a holographic zoom micro-projection system based on three spatial light modulators (SLMs). Three color lasers, three filters, and three solid lenses form the system's ...collimated light sources. Three beam splitters and a prism are used in the system for beam deflection. The SLMs are used as the micro-displays in order to realize phase modulation. A liquid lens, which consists of a circular hole in the center of the middle substrate and several holes around the center, is developed in the system and it. A receiving screen is located behind the liquid lens. When the voltage applied to the liquid lens is changed, the focal length changes accordingly due to electrowetting effect. Three color holograms are loaded on the SLMs, respectively. When three color lasers are used to illuminate the corresponding holograms, the position and size of each color reproduction image can be adjusted by changing the focal length of the liquid lens and holograms loaded onto the SLMs. Therefore, three color images can be reconstructed together perfectly. The proposed system can realize function of zoom micro-projection without chromatic aberration. The experimental results verify its feasibility.
Brown adipocyte in brown adipose tissue (BAT) specializes in expending energy through non-shivering thermogenesis, a process that produces heat either by uncoupling protein 1 (UCP1) dependent ...uncoupling of mitochondrial respiration or by UCP1 independent mechanisms. Apart from this, there is ample evidence suggesting that BAT has an endocrine function. Studies in rodents point toward its vital roles in glucose and lipid homeostasis, making it an important therapeutic target for treating metabolic disorders related to morbidities such as obesity and type 2 diabetes. The rediscovery of thermogenically active BAT depots in humans by several independent research groups in the last decade has revitalized interest in BAT as an even more promising therapeutic intervention. Over the last few years, there has been overwhelming interest in understanding brown adipocyte's developmental lineages and how brown adipocyte uniquely utilizes energy beyond UCP1 mediated uncoupling respiration. These new discoveries would be leveraged for designing novel therapeutic interventions for metabolic disorders.
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