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Summary The manipulation of multiple transcription units for simultaneous and coordinated expression is not only key to building complex genetic circuits to accomplish diverse functions in synthetic biology, but is also important in crop breeding for significantly improved productivity and overall performance. However, building constructs with multiple independent transcription units for fine‐tuned and coordinated regulation is complicated and time‐consuming. Here, we introduce the Multiplex Expression Cassette Assembly (MECA) method, which modifies canonical vectors compatible with Golden Gate Assembly, and then uses them to produce multi‐cassette constructs. By embedding the junction syntax in primers that are used to amplify functional elements, MECA is able to make complex constructs using only one intermediate vector and one destination vector via two rounds of one‐pot Golden Gate assembly reactions, without the need for dedicated vectors and a coherent library of standardized modules. As a proof‐of‐concept, we modified eukaryotic and prokaryotic expression vectors to generate constructs for transient expression of green fluorescent protein and β‐glucuronidase in Nicotiana benthamiana, genome editing to block monoterpene metabolism in tomato glandular trichomes, production of betanin in tobacco and synthesis of β‐carotene in Escherichia coli. Additionally, we engineered the stable production of thymol and carvacrol, bioactive compounds from Lamiaceae family plants, in glandular trichomes of tobacco. These results demonstrate that MECA is a flexible, efficient and versatile method for building complex genetic circuits, which will not only play a critical role in plant synthetic biology, but also facilitate improving agronomic traits and pyramiding traits for the development of next‐generation elite crops. [ABSTRACT FROM AUTHOR]

Previous studies have revealed that Propane-2-sulfonic acid octadec-9-enyl-amide(N15) exerts a protective role in the inflammatory response after ischemic stroke and in neuronal damage. However, little is known about N15 in Alzheimer's disease (AD). The aim of this study was to investigate the effects of N15 on AD and explore the underlying molecular mechanism. AD mice model was established by lateral ventricular injection with Aβ25–35. N15 was daily intraperitoneal administered for 28 days. Morris Water Maze was used to evaluate the neurocognitive function of the mice. The expression of PPARα/γ, brain-derived neurotrophic factor (BDNF), Neurotrophin-3 (NT3), ADAM10, PS1 and BACE1 were measured by qPCR. Aβ amyloid in the hippocampus was measured by Congo red assay. Toluidine blue staining was used to detect the neuronal apoptosis. Protein levels of ADAM10, PS1 and BACE1 were determined using immunoblotting. N15 treatment significantly reduced neurocognitive dysfunction, which also significantly activated the expression of PPARα/γ at an optimal dose of 200 mg/kg. Administration of N15 alleviated the formation of Aβ amyloid in the hippocampus of AD mice, enhanced the BDNF mRNA expression, decreased the mRNA and protein levels of PS1 and BACE1, upregulated ADAM10 mRNA and protein levels. N15 exerts its neuroprotective effects through the activation of PPARα/γ and may be a potential drug for the treatment of AD. [ABSTRACT FROM AUTHOR]

Background This randomized phase 3 study evaluated the efficacy and safety of cinacalcet in children with secondary hyperparathyroidism (SHPT) receiving dialysis. Methods This study had double-blind and open-label phases. Eligible patients aged 6-< 18 years were randomized to cinacalcet (starting dose [less than or equal to] 0.20 mg/kg) or placebo. The primary endpoint was [greater than or equal to] 30% reduction from baseline in mean intact parathyroid hormone (iPTH). Secondary endpoints included mean iPTH [less than or equal to] 300 pg/mL; percentage change from baseline in corrected total serum calcium, phosphorus, and calcium phosphorus product (Ca x P); and safety. Results The double-blind phase comprised 43 patients (cinacalcet, n = 22; placebo, n = 21). Nineteen months into the study, regulatory authorities were notified of a fatality; the study was subsequently terminated after a 14-month clinical hold. Before the hold, 12 patients (55%) on cinacalcet and four (19%) on placebo achieved the primary endpoint (p = 0.017), and 27% and 24%, respectively, achieved iPTH [less than or equal to] 300 pg/mL. The between-group differences (95% CI) in percentage changes for total serum calcium, phosphorus, and Ca x P were - 4% (- 9 to 1%), - 6% (- 21 to 8%), and - 10% (- 23 to 3%). The mean maximum actual weight-adjusted daily cinacalcet dosage administered was 0.99 mg/kg/day. Overall, 82% of patients on cinacalcet and 86% on placebo had [greater than or equal to] 1 treatment-emergent adverse event; the most common were vomiting (32%, 24%, respectively), hypocalcemia (23%, 19%), nausea (18%, 14%), and hypertension (14%, 24%). Conclusions Despite early termination, efficacy and safety outcomes observed with cinacalcet in children with SHPT on dialysis were consistent with adult observations, suggesting cinacalcet may meet an unmet medical need for this population., Author(s): Bradley A. Warady [sup.1] , Janet N. Iles [sup.2] , Gema Ariceta [sup.3] , Bastian Dehmel [sup.4] , Guillermo Hidalgo [sup.5] , Xun Jiang [sup.2] , Benjamin Laskin [sup.6] [...]

Human activity has increased the concentration of the earth's atmospheric carbon dioxide, which plays a direct role in contributing to global warming. Mid-tropospheric CO2 retrieved by the Atmospheric Infrared Sounder shows a substantial spatiotemporal variability that is supported by in situ aircraft measurements. The distribution of middle tropospheric CO2 is strongly influenced by surface sources and large-scale circulations such as the mid-latitude jet streams and by synoptic weather systems, most notably in the summer hemisphere. In addition, the effects of stratosphere-troposphere exchange are observed during a final stratospheric warming event. The results provide the means to understand the sources and sinks and the lifting of CO2 from surface layers into the free troposphere and its subsequent transport around the globe. These processes are not adequately represented in three chemistry-transport models that have been used to study carbon budgets.

To evaluate the efficacy of oral immunization with active kisspeptin DNA vaccine on the expression of hormone receptor mRNA. For this study, ten 56-day-old Hu breed ram lambs were randomly assigned to the treatment and control groups (n = 5). Treatment Experimental group received C500/pKS-asd and the control group received C500/pVAX-asd (aspartate-β semialdehyde dehydrogenase orally on days 0, 28, and 56, and blood samples were taken at each immunization interval (14-day) and tissues samples were collected at the end of the experimental period (day 98). The collected samples were stored in the refrigerator at −20 °C and liquid nitrogen, respectively, for laboratory examination. Total RNA was extracted from samples using TRIzol reagent and quantitative real-time polymerase chain reaction (QPCR) was used to quantify the levels of KISS1, G protein-coupled receptor-54 (Kiss1r), and gonadotrophin-releasing hormone (GnRH) mRNA in the hypothalamus. Levels of luteinizing hormone receptor (LHR) and luteinizing hormone beta (LHβ) mRNA, and follicle-stimulating hormone receptor (FSHR) and follicle-stimulating hormone beta (FSHβ) mRNA in the testes and pituitary were analyzed, respectively. Further, gonadotropin-releasing hormone receptor (GnRHR) mRNA expression level in the pituitary was measured. Moreover, the Kiss1r concentration level in the blood was measured using an indirect ELISA. The concentration of Kiss1r in the blood was lower in the treatment group than in the control group (p < 0.05). The levels of testicular FSHR and LHR mRNA were significantly lower in the treatment group (p < 0.05) when compared to the control group. Furthermore, the treatment group's levels of hypothalamic KISS1, Kiss1r, and GnRH mRNA were significantly lower (p < 0.05) than the controls. LH, FSH, and GnRHR mRNA expression in the pituitary were also significantly lower in the treatment group (p < 0.01 and p < 0.05, respectively). These findings imply that oral immunization with active kisspeptin DNA vaccine suppresses hormone receptor mRNA expression in the ram lambs. [ABSTRACT FROM AUTHOR]

Over the tropical Indo‐Pacific, we explore the variations of Solar‐Induced Fluorescence (SIF), CO2, and precipitation during El Niño Southern Oscillation (ENSO) events verse other times. Based on various data sets, we analyze the time series of deseasonalized precipitation, vertical velocity, SIF, and CO2 across the Indo‐Pacific region. Our analysis reveals that there is less precipitation, more sinking air, lower SIF, and higher carbon dioxide over the Indo‐Pacific region during the El Niño events compared to other times. We also explore the spatial patterns of different variables to gain a deeper understanding of their relationships. The spatial analysis suggests that less precipitation resulting from predominant sinking air not only leads to lower SIF values by reducing photosynthetic activities but also triggers more biomass burning, which contribute to an increase in atmospheric CO2 levels across most areas of the Indo‐Pacific region. The comparative study between observational analyses and numerical simulation by the NOAA CarbonTracker model indicates that the model can simulate the increase of atmospheric column CO2 during the El Niño event, although there are some difficulties in capturing the correct spatial pattern. The results of this study can significantly enhance our understanding of the spatial‐temporal variabilities of atmospheric CO2 concentration and the observational characteristics can be used to enhance models. Furthermore, the complex interactions between ENSO and other variables revealed in this study improve our understanding of how ENSO influences the biosphere and carbon cycle. Key Points: El Niño events suppress Solar‐Induced Fluorescence (photosynthetic activity) and amplify atmospheric CO2 across the Indo‐Pacific regionAdditionally, the release of CO2 from biomass burning during El Niño months contributes to the elevated levels of atmospheric CO2 in the Indo‐Pacific regionModel captures the dominant features of the impact of El Niño Southern Oscillation on CO2 over the Indo‐Pacific region. However, it exhibits limitation in reproducing the spatial pattern of CO2 variations [ABSTRACT FROM AUTHOR]