Calcitonin Receptor Neurons in the Mouse Nucleus Tractus Solitarius Control Energy Balance via the Non-aversive Suppression of Feeding.

To understand hindbrain pathways involved in the control of food intake, we examined roles for calcitonin receptor (CALCR)-containing neurons in the NTS. Ablation of NTS Calcr abrogated the long-term suppression of food intake, but not aversive responses, by CALCR agonists. Similarly, activating CalcrNTS neurons decreased food intake and body weight but (unlike neighboring CckNTS cells) failed to promote aversion, revealing that CalcrNTS neurons mediate a non-aversive suppression of food intake. While both CalcrNTS and CckNTS neurons decreased feeding via projections to the PBN, CckNTS cells activated aversive CGRPPBN cells while CalcrNTS cells activated distinct non-CGRP PBN cells. Hence, CalcrNTS cells suppress feeding via non-aversive, non-CGRP PBN targets. Additionally, silencing CalcrNTS cells blunted food intake suppression by gut peptides and nutrients, increasing food intake and promoting obesity. Hence, CalcrNTS neurons define a hindbrain system that participates in physiological energy balance and suppresses food intake without activating aversive systems

Urban Metabolism of Three Cities in Jing-Jin-Ji Urban Agglomeration, China: Using the MuSIASEM Approach

Urban problems—such as resources depletion, environment pollution and waste generation—usually occur during rapid urbanisation processes, especially in mega-urban agglomerations. Finding solutions to sustainable urban development is a global research interest, and urban metabolism is an effective approach to analysing the socio-economic system and ecosystem. In this study, three cities in the Jing-Jin-Ji urban agglomeration in China—Beijing, Tianjin and Tangshan—were selected as study cases. Multiscale integrated analysis of the societal and ecosystem metabolism (MuSIASEM) method and complete decomposition model were applied to reveal the metabolic characteristics and evolutionary trajectories of the three cities from multiple levels and dimensions. Results showed that the metabolic patterns of Beijing, Tianjin and Tangshan were service-dominated, technology and capital aggregation-dominated and traditional industry-dominated, respectively. The evolution of economic efficiency, ecological pressure and social welfare in the three cities were different because of the stage of urban development where they were located. Tianjin and Tangshan showed positive correlations between economic growth and energy consumption, whereas Beijing demonstrated a more neutral correlation. In the future, issues—such as overpopulation, labour shortage and low efficiency of energy and labour—are likely to be the key factors that impede sustainable development in the three cities, respectively. Several policy implications were raised, including the combination of population dispersal and competitive industry relocation policies for Beijing, attracting young labour in the short term and transforming the economic growth patterns in the long term for Tianjin, and industrial upgrades and technical innovation for Tangshan

Lipoprotein Lipase and Its Regulators : An Unfolding Story

Lipoprotein lipase (LPL) is one of the most important factors in systemic lipid partitioning and metabolism. It mediates intravascular hydrolysis of triglycerides packed in lipoproteins such as chylomicrons and very-low-density lipoprotein (VLDL). Since its initial discovery in the 1940s, its biology and pathophysiological significance have been well characterized. Nonetheless, several studies in the past decade, with recent delineation of LPL crystal structure and the discovery of several new regulators such as angiopoietin-like proteins (ANGPTLs), glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), lipase maturation factor 1 (LMF1) and Sel-1 suppressor of Lin-12-like 1 (SEL1L), have completely transformed our understanding of LPL biology.</p

Rapid Analysis of Aristolochic Acids and Aristolactams in Houttuyniae Herba by LC&ndash;MS/MS

Houttuyniae herba, the Saururaceae plant Houttuynia cordata Thunb., has multiple therapeutic effects, including clearing heat, eliminating toxins, reducing swelling, discharging pus, and relieving stagnation. It has a long history as an edible and medicinal plant in China. Phytochemical studies show that the main constituents include volatile oil, flavonoids, and alkaloids. Aristolactam is a major alkaloid with a structure similar to toxic aristolochic acids. However, there has been no systematic study on aristolochic acids and alkaloids in Houttuyniae herba. Therefore, in this study, an LC&ndash;MS/MS method was developed to simultaneously detect seven alkaloids and five aristolochic acids in Houttuyniae herba from different origins. Six alkaloids (O-demethyl nornucifrine, N-nornucifrine, aristololactam AII, aristololactam FI, aristololactam BII, cepharadione B) were found and quantitatively determined in 75 batches of samples. Meanwhile, no aristolochic acids or aristololactams were found in Houttuyniae herba at a limit of detection (LOD) of &le;4 ng/mL. The method developed was fully validated in terms of LOD, limit of quantification (LOQ), linearity, precision, accuracy, and stability. These data clarify the content of the above safety-related components in Houttuyniae herba and provide a reference for further research into its safety

Rapid Analysis of Aristolochic Acid Analogues in Traditional Chinese Patent Medicine by LC-MS/MS

Aristolochic acids have been demonstrated to have renal toxicity, cause carcinogenesis, and may cause gene mutations. A series of risk control measurements have been adopted worldwide since 1990s. Some varieties of traditional Chinese medicine with high content of aristolochic acids have been banned in China. However, some species containing aristolochic acids in microscale are still in use. In recent years, with the continuous awareness of drug safety, the aristolochic acid analogues were generally considered to be of potential safety risks. Among these constituents, aristolochic acid I is still the one with most studies. Therefore, in addition to aristolochic acid I, it is necessary to establish an accurate and rapid method to determine other aristolochic acid analogues. LC-MS/MS methods based on multireaction monitoring mode was established to simultaneously determine 9 aristolochic acid analogues including 5 aristolochic acids and 4 aristolactams for the first time. Furthermore, the method was applied for Long dan Xie gan Pill, a traditional complex compound preparation with a long history for treatment of diseases including hepatochlic hygropyrexia, dizziness, tinnitus, and deafness. It has attracted widespread attention because of the aristolochic acid nephropathy. The crude drug Caulis Aristolochiae manshuriensis (Guanmutong) collected in the prescription was replaced by Akebiae Caulis (Mutong), and the established method helps to understand the product safety on market. As a result, aristolochic acid I, aristolochic acid Iva, and aristolactam I were detected and determined in one batch of Long dan Xie gan Pill among 25 batches of samples. It provided practical approach to demonstrate trace aristolochic acids and aristolactams. It was beneficial to control the safety of related traditional Chinese medicine products

Comprehensive Evaluation of the Quality of <i>Tripter</i><i>ygium</i> Glycosides Tablets Based on Multi-Component Quantification Combined with an In Vitro Biological Assay

Tripterygium glycosides tablets (TGTs) are widely used in clinical practice to treat rheumatoid arthritis and other autoimmune diseases, with significant beneficial effects but also high toxicity, necessitating rigorous quality evaluation and control. In current study, a rapid resolution liquid chromatography tandem electrospray ionization triple quadrupole mass spectrometry (RRLC–ESI–MS/MS) method was developed and validated for the quantitative analysis of 14 components of ten batches of TGTs produced by different manufacturers, including four diterpenoids, three triterpenoids, and seven sesquiterpene alkaloids. Meanwhile, the NO inhibition effects of these TGTs were evaluated in LPS-induced RAW264.7 cells for their downstream anti-inflammatory activities, as well as their cytotoxicity. The results indicate that the TGTs from different manufacturers showed poor quality consistency, as evidenced by large variations in chemical profiles and biological effects, which may increase the risks associated with clinical use. To improve the quality status of TGTs, it is crucial to identify indicator components whose characterization can accurately reflect the efficacy and toxicity of TGTs from which they were derived. Our study reveals that triptolide, triptoquinone B, celastrol, and demethylzelaysteral considerably contributed to the anti-inflammatory activity and/or cytotoxicity of TGTs, implying that they should be further investigated as candidate indicator components for TGT quality control

Light-Load Efficiency Optimization for an LCC-Parallel Compensated Inductive Power Transfer Battery Charger

Wireless power transfer (WPT) techniques have gained wide acceptance across a range of battery charging applications such as cell phones, cardiac pacemakers, and electric vehicles. In a wireless battery charging system, a constant current/constant voltage (CC/CV) charging strategy, regardless of the variation of the battery load which may roughly range from a few ohms to several hundred ohms, is typically adopted to ensure the safety, durability, and performance of the battery. However, system efficiency drops significantly as the load increases in CV mode, especially at very light-load conditions. This paper proposes an efficiency optimization method for an LCC-parallel compensated inductive power transfer (IPT) battery charging system without the help of any additional power converter and control method. The equivalent circuit and resonant conditions of the LCC-parallel compensation topology are firstly analyzed to achieve the load-independent CV output at a zero phase angle (ZPA) operating frequency. Over the full range of CV charging mode, the efficiency of the LCC-parallel resonant tank circuit is analyzed and optimized. An IPT battery charger prototype with 48 V charging voltage and 1 A charging current is implemented. A measured DC&ndash;DC transfer efficiency of greater than 90.48% is achieved during the whole CV charging profile

Measurement of climate complexity using sample entropy

A climate system is a complex nonlinear system. Estimation of the complexity is of great interest in climatic forecast and prediction. In this paper, we propose the use of sample entropy (SampEn), an entropy-based algorithm, to measure the complexity of daily temperature series. Estimations of SampEn were calculated for 50 meteorological stations in the mountains of Southwest China, particularly in Yunnan Province. On the basis of these data, stations were grouped in climatically homogenous regions (climate provinces), and the spatial pattern of SampEn for each climate province was investigated. The SampEn value of spatial distribution of climate provinces reflects the varying degree of influence of the monsoonal air masses. High SampEn values occur in interactive regions of different air masses, owing to large regional differences in weather processes, while the southwest region is under the influence of the Southwest Monsoon leading to a homogenous climatic environment, low SampEn values and small spatial variations of SampEn. The results suggest that SampEn is an alternative nonlinear approach for analyzing and predicting complexity of climatic time series. Copyright &copy; 2006 Royal Meteorological Society