Towards synergy: network facility development, whole process carbon reduction and pollution reduction, and regional disparities.

The in-depth implementation of the "Broadband China Strategy" is of great significance in promoting the synergistic governance of urban carbon reduction and pollution reduction. In this paper, based on the "Broadband China" pilot program implemented in China in 2014 as a quasi-natural experiment, the coupled synergy model is used to measure the carbon and pollution reduction synergy index based on the balanced panel data of 277 prefectural-level cities and above in China from 2006 to 2020, and the staggered and synthetic DID methods are applied to investigate the impact of the Broadband China strategy on carbon and pollution reduction synergy and its mechanism. strategy on carbon and pollution reduction synergy and its mechanism. The conclusions of the study show that (1) the Broadband China strategy significantly improves the synergistic governance of carbon reduction and pollution reduction. (2) The mechanism results show that Broadband China mainly realizes carbon and pollution synergistic governance by promoting source control and process innovation but does not have an effective mediating role in end-of-pipe treatment. (3) The results of heterogeneity analysis show that Broadband China weakens the traditional geographic advantage, narrows the carbon pollution synergistic governance gap at the national and regional levels, and significantly improves the regional carbon reduction and pollution reduction governance level. This paper examines the micro-mechanism of the Broadband China strategy on carbon pollution synergistic governance from the whole process of production activities, which provides a new perspective for the study of carbon pollution synergistic governance, and provides an empirical basis for carbon pollution synergistic governance in China.

Evaluation on evolution of spatial relationship between carbon emissions and economic growth in Beijing-Tianjin-Hebei region.

The Beijing-Tianjin-Hebei region is not only an important economic center in China, but also one of the major regions contributing to China's carbon emissions. Revealing the spatial distribution between carbon emissions and economic growth is essential for the formulation of low-carbon development policies. Following the principle from macro to micro, this paper investigates the spatial evolution trend and distribution characteristics between carbon emissions and economic growth in the Beijing-Tianjin-Hebei region from 2005 to 2020 by applying imbalance index model, the rank-scale rule, and decoupling index model. The results show that the imbalance index of carbon emissions decreased between 0.0601 and 0.0533 in a fluctuating way, indicating that the imbalance of spatial distribution of carbon emissions decreases. The imbalance index of economic growth increased between 0.0738 and 0.0851, indicating that economic growth has become more disequilibrated, and the spatial evolution of carbon emissions is not coordinated with economic growth. The Zipf dimension of carbon emissions declined from 1.1806 in 2005 to 0.9594 in 2020, and carbon emissions declined in big cities and increased in cities of the middle order. The Zipf dimension of economic growth increased from 1.1384 in 2005 to 1.2388 in 2020, and the economic growth monopoly in big cities increased. The decoupling coefficient of carbon emissions to economic growth declined, and the driving effect of economic growth on carbon emissions diminished. It is recommended that the Beijing-Tianjin-Hebei region should coordinate the allocation of factors and coordinate industrial adjustment. Hebei should accelerate industrial upgrading and establish a diversified industrial system.

Investigating the impacts of poverty alleviation on carbon emissions and its mechanisms.

Exploring the relationship between poverty alleviation and carbon emissions can provide theoretical foundations for inclusive low-carbon development. This study empirically explores the impact of poverty alleviation on carbon emissions and its underlying mechanisms using panel data from Chinese provinces from 2007 to 2020. (1) The benchmark regression results indicate that poverty alleviation increases carbon emissions, and this result is robust. (2) Mechanism analysis reveals that promoting the transformation from the primary industry to the secondary industry and fostering consumption growth are important paths for poverty alleviation that promote carbon emissions. (3) Heterogeneity regression results show that effect of poverty alleviation on carbon emissions is more pronounced in impoverished provinces and resource-rich provinces. This study reveals the conflict between poverty alleviation and carbon emissions reduction in China, and reminds the government of the need to implement low-carbon poverty alleviation policies as well as guide people to low-carbon consumption.

Relationship between caffeine intake and thyroid function: results from NHANES 2007-2012.

BACKGROUND: Moderate caffeine intake decreases the risk of metabolic disorders and all-cause mortality, and the mechanism may be related to its ergogenic actions. Thyroid hormones are vital in metabolic homeostasis; however, their association with caffeine intake has rarely been explored. OBJECTIVE: To investigate the association between caffeine intake and thyroid function. METHODS: We collected data on demographic background, medical conditions, dietary intake, and thyroid function from the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Subgroups were classified using two-step cluster analysis, with sex, age, body mass index (BMI), hyperglycemia, hypertension, and cardio-cerebral vascular disease (CVD) being used for clustering. Restrictive cubic spline analysis was employed to investigate potential nonlinear correlations, and multivariable linear regression was used to evaluate the association between caffeine consumption and thyroid function. RESULTS: A total of 2,582 participants were included, and three subgroups with different metabolic features were clustered. In the most metabolically unhealthy group, with the oldest age, highest BMI, and more cases of hypertension, hyperglycemia, and CVD, there was a nonlinear relationship between caffeine intake and serum thyroid stimulating hormone (TSH) level. After adjusting for age, sex, race, drinking, smoking, medical conditions, and micronutrient and macronutrient intake, caffeine intake of less than 9.97 mg/d was positively associated with serum TSH (p = 0.035, standardized ß = 0.155); however, moderate caffeine consumption (9.97-264.97 mg/d) indicated a negative association (p = 0.001, standardized ß = - 0.152). CONCLUSIONS: Caffeine consumption had a nonlinear relationship with serum TSH in people with metabolic disorders, and moderate caffeine intake (9.97 ~ 264.97 mg/d) was positively associated with serum TSH.

Chronic cortisol exposure in early development leads to neuroendocrine dysregulation in adulthood.

OBJECTIVE: Chronic early life stress can affect development of the neuroendocrine stress system, leading to its persistent dysregulation and consequently increased disease risk in adulthood. One contributing factor is thought to be epigenetic programming in response to chronic cortisol exposure during early development. We have previously shown that zebrafish embryos treated chronically with cortisol develop into adults with constitutively elevated whole-body cortisol and aberrant immune gene expression. Here we further characterize that phenotype by assessing persistent effects of the treatment on cortisol tissue distribution and dynamics, chromatin accessibility, and activities of glucocorticoid-responsive regulatory genes klf9 and fkbp5. To that end cortisol levels in different tissues of fed and fasted adults were measured using ELISA, open chromatin in adult blood cells was mapped using ATAC-seq, and gene activity in adult blood and brain cells was measured using qRT-PCR. RESULTS: Adults derived from cortisol-treated embryos have elevated whole-body cortisol with aberrantly regulated tissue distribution and dynamics that correlate with differential activity of klf9 and fkbp5 in blood and brain.

Klf9 is a key feedforward regulator of the transcriptomic response to glucocorticoid receptor activity.

The zebrafish has recently emerged as a model system for investigating the developmental roles of glucocorticoid signaling and the mechanisms underlying glucocorticoid-induced developmental programming. To assess the role of the Glucocorticoid Receptor (GR) in such programming, we used CRISPR-Cas9 to produce a new frameshift mutation, GR369-, which eliminates all potential in-frame initiation codons upstream of the DNA binding domain. Using RNA-seq to ask how this mutation affects the larval transcriptome under both normal conditions and with chronic cortisol treatment, we find that GR mediates most of the effects of the treatment, and paradoxically, that the transcriptome of cortisol-treated larvae is more like that of larvae lacking a GR than that of larvae with a GR, suggesting that the cortisol-treated larvae develop GR resistance. The one transcriptional regulator that was both underexpressed in GR369- larvae and consistently overexpressed in cortisol-treated larvae was klf9. We therefore used CRISPR-Cas9-mediated mutation of klf9 and RNA-seq to assess Klf9-dependent gene expression in both normal and cortisol-treated larvae. Our results indicate that Klf9 contributes significantly to the transcriptomic response to chronic cortisol exposure, mediating the upregulation of proinflammatory genes that we reported previously.

Simple and fast quantification of DNA damage by real-time PCR, and its application to nuclear and mitochondrial DNA from multiple tissues of aging zebrafish.

We describe a real-time (rt) PCR-based method of quantifying DNA damage, adapted from the long-run rtPCR method of DNA damage quantification (LORD-Q) developed by Lehle et al. (Nucleic Acids Res 42(6):e41, 2014). We show that semi-long run rtPCR, which generates amplicons half the length of those generated in LORD-Q, provides equivalent sensitivity for detecting low lesion frequencies, and better sensitivity for detecting high frequencies. The smaller amplicon size greatly facilitates PCR optimization and allows greater flexibility in the use of detection dyes, and a modified data analysis method simplifies the calculation of lesion frequency. The method was used to measure DNA damage in the nuclear and mitochondrial genomes of different tissues in zebrafish of different ages. We find that nuclear DNA damage generally increases with age, and that the amount of mitochondrial DNA damage varies substantially between tissues, increasing with age in liver and brain but not in heart or skeletal muscle, the latter having the highest levels of damage irrespective of age.

Cortisol-treated zebrafish embryos develop into pro-inflammatory adults with aberrant immune gene regulation.

Chronic early-life stress increases adult susceptibility to numerous health problems linked to chronic inflammation. One way that this may occur is via glucocorticoid-induced developmental programming. To gain insight into such programming we treated zebrafish embryos with cortisol and examined the effects on both larvae and adults. Treated larvae had elevated whole-body cortisol and glucocorticoid signaling, and upregulated genes associated with defense response and immune system processes. In adulthood the treated fish maintained elevated basal cortisol levels in the absence of exogenous cortisol, and constitutively mis-expressed genes involved in defense response and its regulation. Adults derived from cortisol-treated embryos displayed defective tailfin regeneration, heightened basal expression of pro-inflammatory genes, and failure to appropriately regulate those genes following injury or immunological challenge. These results support the hypothesis that chronically elevated glucocorticoid signaling early in life directs development of a pro-inflammatory adult phenotype, at the expense of immunoregulation and somatic regenerative capacity.

An intact putative mouse telomerase essential N-terminal domain is necessary for proper telomere maintenance.

BACKGROUND INFORMATION: Naturally occurring telomerase reverse transcriptase (TERT) isoforms may regulate telomerase activity, and possibly function independently of telomeres to modulate embryonic stem (ES) cell self-renewal and differentiation. RESULTS: We report the characterisation of two novel mouse TERT (mTERT) splice variants, Ins-i1[1-102] (Insi1 for short) and Del-e12[1-40] (Dele12 for short) that have not been previously described. Insi1 represents an in-frame insertion of nucleotides 1-102 from intron 1, encoding a 34 amino acid insertion at amino acid 73. Based on known functions of this region in human and Tetrahymena TERTs, the insertion interrupts the RNA interaction domain 1 implicated in low-affinity RNA binding and the telomerase essential N-terminal domain implicated in DNA substrate interactions. Dele12 contains a 40 nucleotide deletion of exon 12 which generates a premature stop codon, and possible protein lacking the C-terminus. We found Insi1 expressed in adult mouse brain and kidney and Dele12 expressed in adult mouse ovary. Dele12 was inactive in vitro and in mTERT(-/-) ES cells and Insi1 retained 26-48% of telomerase activity reconstituted by wild-type mTERT in vitro and in mTERT(-/-) ES cells. The Insi1 variant exhibited reduced DNA substrate binding in vitro and both variants exhibited a reduction in binding the telomerase RNA, mTR, when expressed in mTERT(-/-) ES cells. Stable expression of Dele12 in the mouse fibroblast CB17 cell line inhibited telomerase activity and slowed cell growth, suggesting a potential dominant-negative effect. Levels of signal-free ends, representing short telomeres, and end-to-end fusions were higher in mTERT(-/-) ES cells expressing mTERT-Insi1 and mTERT-Dele12, compared with levels observed in mTERT(-/-) ES cells expressing wild-type mTERT. In addition, in mTERT(-/-) cells expressing mTERT-Insi1, we observed chromosomes that were products of repeated breakage-bridge-fusion cycles and other telomere dysfunction-related aberrations. CONCLUSION AND SIGNIFICANCE: An intact mTERT N-terminus which contributes to mTR binding, DNA binding and telomerase activity is necessary for elongation of short telomeres and the maintenance of functional telomeres. It is reasonable to speculate that relative levels of mTERT-Insi1 may regulate telomere function in specific tissues.

Inactive C-terminal telomerase reverse transcriptase insertion splicing variants are dominant-negative inhibitors of telomerase.

Maintenance of telomere length and structure is essential for cell survival. Telomere synthesis is mediated by the ribonucleoprotein telomerase in 90% of cancer cells, and is regulated mainly by transcription of the human telomerase reverse transcriptase subunit, hTERT. However, transcriptome analysis reveals complex splicing patterns and to date, twenty-two alternatively-spliced hTERT mRNAs have been reported, yet their functions have not been fully elucidated. The best characterized hTERT spliced variants encode for inactive proteins that possess specific deletions within the hTERT catalytic domains. We studied two less well characterized hTERT splice variants (termed INS3 and 4) that encode proteins with intact reverse transcriptase motifs, but alternative C-domains due to insertion of intronic sequences. We determined the prevalence of these mRNA variants in primary cells, telomerase-positive cells and in alternative lengthening of telomere (ALT) cells and found the transcripts to be expressed mainly in telomerase-positive cell lines and to be translated into proteins as illustrated by their association with polysomes. These variants were inactive when expressed in vitro or in cells, retained DNA substrate binding in vitro but were impaired in binding the telomerase RNA component when expressed in, and immunoprecipitated from either telomerase-positive or telomerase-negative ALT cells coexpressing the telomerase RNA component. Stable expression of INS3 and INS4 variants in a hepatocarcinoma cell line inhibited telomerase activity, shortened telomeres and slowed cell growth suggesting a potential dominant-negative function.

Telomerase inhibition in a mouse cell line with long telomeres leads to rapid telomerase reactivation.

The indefinite growth of cancer cells requires telomere maintenance, which, in the majority of mammalian cancers is mediated via the enzyme telomerase. The core components of telomerase are a catalytic reverse transcriptase (hTERT in human, mTERT in mouse) and an RNA (TR) that contains the template for the replenishment of telomeres. Fundamental differences in human and mouse telomerase and telomere biology should be considered when using mouse models for the study of human cancers. The responses to telomerase inhibition by the expression of a catalytically-inactive dominant-negative mutant of hTERT (hTERT-DN) vary in human cells with different telomere lengths. Only one similar study has been performed in a mouse cell line with short telomeres (RenCa, 7 kb). Thus, we asked whether the responses to telomerase inhibition are also telomere-length dependent in mouse cells by analyzing long-term stable expression of mTERT-DN in the CB17 cell line (telomere length, 11 kb). A brief initial telomerase inhibition was insufficient to mediate telomere shortening and led to extremely rapid telomerase reactivation due to an increase in the level of expression of the endogenous mTERT. Thus, mouse cells, in contrast to human cells may not tolerate telomerase inhibition by introduction of mTERT-DN, independently of telomere length.