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1.
Proc Natl Acad Sci U S A ; 121(28): e2403130121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38950369

RESUMO

DNA polymerase κ (Polκ) is a specialized polymerase that has multiple cellular roles such as translesion DNA synthesis, replication of repetitive sequences, and nucleotide excision repair. We have developed a method for capturing DNA synthesized by Polκ utilizing a Polκ-specific substrate, N2-(4-ethynylbenzyl)-2'-deoxyguanosine (EBndG). After shearing of the DNA into 200 to 500 bp lengths, the EBndG-containing DNA was covalently bound to biotin using the Cu(I)-catalyzed alkyne-azide cycloaddition reaction and isolated with streptavidin beads. Isolated DNA was then ligated to adaptors, followed by PCR amplification and next-generation sequencing to generate genome-wide repair maps. We have termed this method polymerase κ sequencing. Here, we present the human genome maps for Polκ activity in an undamaged cell line. We found that Polκ activity was enhanced in GC-rich regions, euchromatin regions, the promoter of genes, and in DNA that is replicated early in the S phase.


Assuntos
DNA Polimerase Dirigida por DNA , Fibroblastos , Genoma Humano , Humanos , DNA Polimerase Dirigida por DNA/metabolismo , Fibroblastos/metabolismo , Reparo do DNA , DNA/metabolismo , DNA/genética , Linhagem Celular , Replicação do DNA
2.
Nicotine Tob Res ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38513068

RESUMO

INTRODUCTION: Cigarette smoking remains the leading preventable cause of disease and death. Nicotine is the primary reinforcing ingredient in cigarettes sustaining addiction. Cotinine is the major metabolite of nicotine that produces a myriad of neurobehavioral effects. Previous studies showed that cotinine supported self-administration in rats and rats with a history of cotinine self-administration exhibited relapse-like drug-seeking behavior, suggesting that cotinine may also be reinforcing. To date, whether cotinine may contribute to nicotine reinforcement remains unknown. Nicotine metabolism is mainly catalyzed by hepatic CYP2B1/2 enzymes in rats and methoxsalen is a potent CYP2B1/2 inhibitor. METHODS: The study examined nicotine metabolism, self-administration, and locomotor activity. The hypothesis is that methoxsalen inhibits nicotine self-administration and cotinine replacement attenuates the inhibitory effects of methoxsalen in male rats. RESULTS: Methoxsalen decreased plasma cotinine levels following a subcutaneous nicotine injection. Repeated daily methoxsalen treatments reduced the acquisition of nicotine self-administration, leading to fewer nicotine infusions, lower nicotine intake, and lower plasma cotinine levels. However, methoxsalen did not alter the maintenance of nicotine self-administration despite a significant reduction of plasma cotinine levels. Cotinine replacement by mixing cotinine with nicotine for self-administration dose-dependently increased plasma cotinine levels and enhanced the acquisition of self-administration. Neither basal nor nicotine-induced locomotor activity was altered by methoxsalen. CONCLUSIONS: These results indicate that methoxsalen inhibition of cotinine formation impaired the acquisition of nicotine self-administration, and cotinine replacement attenuated the inhibitory effects of methoxsalen on the acquisition of self-administration, suggesting that cotinine may contribute to the initial development of nicotine reinforcement. IMPLICATIONS: Smoking cessation medications targeting nicotine's effects are only moderately effective, making it imperative to better understand the mechanisms of nicotine misuse. Methoxsalen inhibited nicotine metabolism to cotinine and impaired the acquisition of nicotine self-administration. Cotinine replacement restored plasma cotinine and attenuated the methoxsalen inhibition of nicotine self-administration in rats. These results suggest that (1) the inhibition of nicotine metabolism may be a viable strategy in reducing the development of nicotine reinforcement, (2) methoxsalen may be translationally valuable, and (3) cotinine may be a potential pharmacological target for therapeutic development given its important role in the initial development of nicotine reinforcement.

3.
J Dairy Sci ; 106(4): 2535-2550, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36797187

RESUMO

Longitudinal traits, such as milk production traits in dairy cattle, are featured by having phenotypic values at multiple time points, which change dynamically over time. In this study, we first imputed SNP chip (50-100K) data to whole-genome sequence (WGS) data in a Chinese Holstein population consisting of 6,470 cows. The imputation accuracies were 0.88 to 0.97 on average after quality control. We then performed longitudinal GWAS in this population based on a random regression test-day model using the imputed WGS data. The longitudinal GWAS revealed 16, 39, and 75 quantitative trait locus regions associated with milk yield, fat percentage, and protein percentage, respectively. We estimated the 95% confidence intervals (CI) for these quantitative trait locus regions using the logP drop method and identified 581 genes involved in these CI. Further, we focused on the CI that covered or overlapped with only 1 gene or the CI that contained an extremely significant top SNP. Twenty-eight candidate genes were identified in these CI. Most of them have been reported in the literature to be associated with milk production traits, such as DGAT1, HSF1, MGST1, GHR, ABCG2, ADCK5, and CSN1S1. Among the unreported novel genes, some also showed good potential as candidate genes, such as CCSER1, CUX2, SNTB1, RGS7, OSR2, and STK3, and are worth being further investigated. Our study provided not only new insights into the candidate genes for milk production traits, but also a general framework for longitudinal GWAS based on random regression test-day model using WGS data.


Assuntos
Estudo de Associação Genômica Ampla , Leite , Animais , Bovinos/genética , Feminino , Estudo de Associação Genômica Ampla/veterinária , Genótipo , Leite/metabolismo , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Estudos Longitudinais
4.
Molecules ; 28(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36677723

RESUMO

Genetic improvement of milk fatty acid content traits in dairy cattle is of great significance. However, chromatography-based methods to measure milk fatty acid content have several disadvantages. Thus, quick and accurate predictions of various milk fatty acid contents based on the mid-infrared spectrum (MIRS) from dairy herd improvement (DHI) data are essential and meaningful to expand the amount of phenotypic data available. In this study, 24 kinds of milk fatty acid concentrations were measured from the milk samples of 336 Holstein cows in Shandong Province, China, using the gas chromatography (GC) technique, which simultaneously produced MIRS values for the prediction of fatty acids. After quantification by the GC technique, milk fatty acid contents expressed as g/100 g of milk (milk-basis) and g/100 g of fat (fat-basis) were processed by five spectral pre-processing algorithms: first-order derivative (DER1), second-order derivative (DER2), multiple scattering correction (MSC), standard normal transform (SNV), and Savitzky-Golsy convolution smoothing (SG), and four regression models: random forest regression (RFR), partial least square regression (PLSR), least absolute shrinkage and selection operator regression (LassoR), and ridge regression (RidgeR). Two ranges of wavebands (4000~400 cm-1 and 3017~2823 cm-1/1805~1734 cm-1) were also used in the above analysis. The prediction accuracy was evaluated using a 10-fold cross validation procedure, with the ratio of the training set and the test set as 3:1, where the determination coefficient (R2) and residual predictive deviation (RPD) were used for evaluations. The results showed that 17 out of 31 milk fatty acids were accurately predicted using MIRS, with RPD values higher than 2 and R2 values higher than 0.75. In addition, 16 out of 31 fatty acids were accurately predicted by RFR, indicating that the ensemble learning model potentially resulted in a higher prediction accuracy. Meanwhile, DER1, DER2 and SG pre-processing algorithms led to high prediction accuracy for most fatty acids. In summary, these results imply that the application of MIRS to predict the fatty acid contents of milk is feasible.


Assuntos
Lactação , Leite , Animais , Feminino , Bovinos , Leite/química , Ácidos Graxos/análise , Espectrofotometria Infravermelho/métodos , Análise dos Mínimos Quadrados
5.
Carcinogenesis ; 43(8): 746-753, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-35749296

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are recognized as potential etiological agents in the development of oral cancer in smokers. In particular, benzo[a]pyrene (B[a]P) and dibenzo[def,p]chrysene (DB[a,l]P) are detected in cigarette smoke and the environment and can induce DNA damage, mutagenesis and carcinogenesis in the oral cavity of rodents. Consequently, DNA adducts are regarded as the most direct markers of genotoxicity and can be used as biomarkers of cancer risk. Thus, this study used LC-MS/MS analysis with isotope labeled internal standard to detect and quantify DNA adducts derived from B[a]P and DB[a,l]P in buccal cells of cigarette smokers and non-smokers. Participants in this study include 21 smokers and 16 non-smokers. Our data are the first to report that levels (mean ± SD) of BPDE-N2-dG were significantly (P < 0.001) higher in smokers (20.18 ± 8.40 adducts/108 dG) than in non-smokers (0.84 ± 1.02 adducts/108 dG). Likewise, levels of DBPDE-N6-dA in smokers (5.49 ± 3.41 adducts/108 dA) were significantly higher (P = 0.019) than non-smokers (2.76 ± 2.29 adducts/108 dA). Collectively, the results of this clinical study support that PAHs in tobacco smoke can contribute to the development of oral cancer in humans.


Assuntos
Neoplasias Bucais , Hidrocarbonetos Policíclicos Aromáticos , Produtos do Tabaco , Poluição por Fumaça de Tabaco , Benzo(a)pireno/toxicidade , Carcinógenos/análise , Carcinógenos/toxicidade , Cromatografia Líquida , Crisenos/análise , Adutos de DNA , Humanos , Mucosa Bucal , Neoplasias Bucais/induzido quimicamente , Neoplasias Bucais/genética , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Espectrometria de Massas em Tandem , Nicotiana/efeitos adversos , Produtos do Tabaco/toxicidade
6.
BMC Genomics ; 23(1): 41, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35012443

RESUMO

BACKGROUND: The early death and health problems of calves caused substantial economic losses in the dairy industry. As the immune system of neonates has not been fully developed, the absorption of maternal immunoglobulin (Ig) from colostrum is essential in protecting newborn calves against common disease organisms in their early life. The overwhelming majority of Ig in bovine whey is transported from the serum. Therefore, Ig concentration in the colostrum and serum of dairy cows are critical traits when estimating the potential disease resistance of its offspring. RESULTS: Colostrum, blood, and hair follicle samples were collected from 588 Chinese Holstein cows within 24 h after calving. The concentration of total IgG, IgG1, IgG2, IgA and IgM in both colostrum and serum were detected via ELISA methods. With GCTA software, genome-wide association studies (GWASs) were performed with 91,620 SNPs genotyped by GeneSeek 150 K (140,668 SNPs) chips. As a result, 1, 5, 1 and 29 significant SNPs were detected associated with the concentrations of colostrum IgG1, IgG2, IgA IgM, and serum IgG2 at the genome-wide level (P < 3.08E-6); 11, 2, 13, 2, 12, 8, 2, 27, 1 and 4 SNPs were found significantly associated with total IgG, IgG1, IgG2, IgA and IgM in colostrum and serum at the suggestive level (P < 6.15E-5). Such SNPs located in or proximate to (±1 Mb) 423 genes, which were functionally implicated in biological processes and pathways, such as immune response, B cell activation, inflammatory response and NF-kappaB signaling pathways. By combining the biological functions and the known QTL data for immune traits in bovine, 14 promising candidate functional genes were identified for immunoglobulin concentrations in colostrum and serum in dairy cattle, they were FGFR4, FGFR2, NCF1, IKBKG, SORBS3, IGHV1S18, KIT, PTGS2, BAX, GRB2, TAOK1, ICAM1, TGFB1 and RAC3. CONCLUSIONS: In this study, we identified 14 candidate genes related to concentrations of immunoglobulins in colostrum and serum in dairy cattle by performing GWASs. Our findings provide a groundwork for unraveling the key genes and causal mutations affecting immunoglobulin concentrations in colostrum and important information for genetic improvement of such traits in dairy cattle.


Assuntos
Colostro , Estudos de Associação Genética/veterinária , Animais , Animais Recém-Nascidos , Bovinos , China , Indústria de Laticínios , Feminino , Imunoglobulina G , Gravidez
7.
Chem Res Toxicol ; 35(11): 2152-2159, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36260657

RESUMO

In a series of previous studies we reported that black raspberry (BRB) powder inhibits dibenzo[a,l]pyrene (DBP)-induced DNA damage, mutagenesis, and oral squamous cell carcinoma (OSCC) development in mice. In the present study, using human oral leukoplakia (MSK-Leuk1) and squamous cell carcinoma (SCC1483) cells, we tested the hypothesis that BRB extract (BRBE) will enhance the synthesis of glutathione (GSH) and in turn increase GSH conjugation of the fjord-region DBP diol epoxide (DBPDE) derived from DBP leading to inhibition of DBP-induced DNA damage. The syntheses of DBPDE-GSH conjugate, DBPDE-dA adduct, and the corresponding isotope-labeled internal standards were performed; LC-MS/MS methods were used for their quantification. BRBE significantly (p < 0.05) increased cellular GSH by 31% and 13% at 6 and 24 h, respectively, in OSCC cells; in MSK-LeuK1 cells, the levels of GSH significantly (p < 0.05) increased by 55% and 22%, at 1 and 6 h. Since BRBE significantly enhanced the synthesis of GSH in both cell types, subsequent experiments were performed in MSK-Leuk1 cells. Western blot analysis was performed to determine the types of proteins involved in the synthesis of GSH. BRBE significantly (p < 0.05) increased the protein expression (2.5-fold) of the glutamate-cysteine ligase catalytic subunit (GCLC) but had no effect on the glutamate-cysteine ligase modifier subunit (GCLM) and glutathione synthetase (GSS). LC-MS/MS analysis showed that pretreatment of cells with BRBE followed by DBPDE significantly (p < 0.05) increased the levels of DBPDE-GSH conjugate (2.5-fold) and decreased DNA damage by 74% measured by assessing levels of DBPDE-dA adduct formation. Collectively, the results of this in vitro study clearly support our hypothesis, and the LC-MS/MS methods developed in the present study will be highly useful in testing the same hypothesis initially in our mouse model and ultimately in smokers.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Rubus , Humanos , Camundongos , Animais , Carcinógenos , Crisenos , Benzopirenos/metabolismo , Compostos de Epóxi , Nicotiana/metabolismo , Glutamato-Cisteína Ligase , Adutos de DNA , Cromatografia Líquida , Estuários , Neoplasias Bucais/induzido quimicamente , Espectrometria de Massas em Tandem , Glutationa/metabolismo , Extratos Vegetais/farmacologia
8.
FASEB J ; 35(5): e21455, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33913197

RESUMO

Mammal's milk is an abundantly foremost source of proteins, lipids, and micronutrients for human nutrition and health. Understanding the molecular mechanisms underlying synthesis of milk components provides practical benefits to improve the milk quality via systematic breeding program in mammals. Through RNAi with EEF1D in primary bovine mammary epithelial cells, we phenotypically observed aberrant formation of cytoplasmic lipid droplets and significantly decreased milk triglyceride level by 37.7%, and exploited the mechanisms by which EEF1D regulated milk lipid synthesis via insulin (PI3K-Akt), AMPK, and PPAR pathways. In the EEF1D CRISPR/Cas9 knockout mice, incompletely developed mammary glands at 9th day postpartum with small or unformed lumens, and significantly decreased triglyceride concentration in milk by 23.4% were observed, as well as the same gene expression alterations in the three pathways. For dairy cattle, we identified a critical regulatory mutation modifying EEF1D transcription activity, which interpreted 7% of the genetic variances of milk lipid yield and percentage. Our findings highlight the significance of EEF1D in mammary gland development and milk lipid synthesis in mammals.


Assuntos
Lipídeos/biossíntese , Lipogênese , Glândulas Mamárias Animais/metabolismo , Leite/metabolismo , Fator 1 de Elongação de Peptídeos/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética
9.
Behav Pharmacol ; 33(5): 364-378, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35695511

RESUMO

Substance use disorder is challenging to treat due to its relapsing nature. In the last decade, opioid use disorder has been a threat to public health, being declared an epidemic by the Centers for Disease Control and Prevention. This is a tragic situation, considering there currently are only three effective, yet not ideal, treatments to prevent relapse to opioids. Recent research has shown that hormones that modulate hunger and satiety also can modulate motivated behavior for drugs of abuse. For example, the short-acting analog of glucagon-like peptide-1 (GLP-1), an incretin hormone that regulates homeostatic feeding, has been shown to reduce responding for rewarding stimuli such as food, cocaine, heroin, and nicotine when administered over several days or weeks. This may serve as an effective adjuvant during treatment; however, whether it would be effective when used acutely to bridge a patient between cessation of use and onset of medication for the treatment of an opioid addiction is unknown. Here, we tested the acute effects of the longer acting GLP-1 analog, liraglutide, on heroin-seeking. In rats with heroin self-administration experience, we found that subcutaneous administration of an acute dose of 0.3-mg/kg liraglutide was effective in preventing drug-seeking after exposure to three major precipitators: drug-associated cues, stress (yohimbine-induced), and the drug itself. Finally, we confirmed that the reduction in drug-seeking is not due to a locomotor impairment, as liraglutide did not significantly alter performance in a rotarod test. As such, acute use of GLP-1 analogs may serve as a new and effective nonopioid bridge to treatment.


Assuntos
Sinais (Psicologia) , Heroína , Animais , Comportamento de Procura de Droga , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Heroína/farmacologia , Liraglutida/farmacologia , Ratos , Autoadministração
10.
Anim Genet ; 53(3): 422-426, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35292995

RESUMO

As a member of the fatty acid desaturase family, fatty acid desaturase 2 (FADS2) gene is a rate-limiting enzyme in the synthesis of unsaturated fatty acids and within/near to the reported QTL regions for milk-production traits. We previously found that FADS2 is differentially expressed during different lactations of Chinese Holstein cows, and participates in lipid metabolic processes by influencing the insulin, PI3K-Akt, MAPK, AMPK, mTOR and PPAR signaling pathways. Therefore, we considered this gene as a candidate gene for milk-production traits. In this study, we identified 12 SNPs in FADS2 by re-sequencing, including two SNPs in the 5' flanking region, one in the seventh exon, five in introns, two in the 3' untranslated region and two in the 3' flanking region. The 29:g.40378819C>T is a missense mutation that causes alanine (GCG) to be replaced with valine (GTG). Through single marker association analysis, we found that all of the 12 SNPs were significantly associated with 305 day milk yield, fat yield, fat percentage, protein yield or protein percentage (p < 0.0493). The results of the subsequent haplotype association analysis also confirmed the associations between the gene and milk-production traits. In summary, this study suggests that there is a significant genetic association between FADS2 and milk-production traits, and that the SNPs with significant genetic effects can provide important molecular information for the development of a genomic selection chip in dairy cattle.


Assuntos
Leite , Fosfatidilinositol 3-Quinases , Regiões 3' não Traduzidas , Animais , Bovinos/genética , China , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Feminino , Lactação/genética , Leite/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Polimorfismo de Nucleotídeo Único
11.
BMC Genomics ; 22(1): 575, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315401

RESUMO

BACKGROUND: Our previous genome-wide association study (GWAS) on milk fatty acid traits in Chinese Holstein cows revealed, the SNP, BTB-01556197, was significantly associated with C10:0 at genome-wide level (P = 0.0239). It was located in the down-stream of 5-hydroxytryptamine receptor 1B (HTR1B) gene that has been shown to play an important role in the regulation of fatty acid oxidation. Hence, we considered it as a promising candidate gene for milk fatty acids in dairy cattle. In this study, we aimed to investigate whether the HTR1B gene had significant genetic effects on milk fatty acid traits. RESULTS: We re-sequenced the entire coding region and 3000 bp of 5' and 3' flanking regions of HTR1B gene. A total of 13 SNPs was identified, containing one in 5' flanking region, two in 5' untranslated region (UTR), two in exon 1, five in 3' UTR, and three in 3' flanking region. By performing genotype-phenotype association analysis with SAS9.2 software, we observed that 13 SNPs were significantly associated with medium-chain saturated fatty acids such as C6:0, C8:0 and C10:0 (P < 0.0001 ~ 0.042). With Haploview 4.1 software, linkage disequilibrium (LD) analysis was performed. Two haplotype blocks formed by two and ten SNPs were observed. Haplotype-based association analysis indicated that both haplotype blocks were strongly associated with C6:0, C8:0 and C10:0 as well (P < 0.0001 ~ 0.0071). With regards to the missense mutation in exon 1 (g.17303383G > T) that reduced amino acid change from alanine to serine, we predicted that it altered the secondary structure of HTR1B protein with SOPMA. In addition, we predicted that three SNPs in promoter region, g.17307103A > T, g.17305206 T > G and g.17303761C > T, altered the binding sites of transcription factors (TFs) HMX2, PAX2, FOXP1ES, MIZ1, CUX2, DREAM, and PPAR-RXR by Genomatix. Of them, luciferase assay experiment further confirmed that the allele T of g.17307103A > T significantly increased the transcriptional activity of HTR1B gene than allele A (P = 0.0007). CONCLUSIONS: In conclusion, our findings provided first evidence that the HTR1B gene had significant genetic effects on milk fatty acids in dairy cattle.


Assuntos
Ácidos Graxos , Leite , Animais , Bovinos/genética , Feminino , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Serotonina
12.
BMC Public Health ; 21(1): 1025, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059023

RESUMO

BACKGROUND: Over one-quarter of all smokers in the United States identify as non-daily smokers and this number is projected to rise. Unlike daily smokers who typically maintain consistent levels of nicotine exposure with regular smoking, non-daily smokers have variable patterns of smoking that likely result in high intraindividual variability in nicotine intake. The current study aimed to characterize the weekly intraindividual variability in cotinine and identify smoking-related predictors in nondaily smokers. METHODS: An ecological momentary assessment of 60 non-daily smokers ages 24-57 years was conducted over a consecutive 7-day at-home protocol to log each smoking session, assessments of mood and social activity during smoking, and collection of daily saliva samples in a convenience sample from Pennsylvania, USA. Hierarchical linear regression analyses were conducted to determine the effects of smoking characteristics on total cotinine exposure measured by pharmacokinetic area under the curve and the range, maximum, and minimum cotinine values during the week controlling for demographic variables. RESULTS: The mean daily cotinine level was 119.2 ng/ml (SD = 168.9) with individual values that ranged from nondetectable to 949.6 ng/ml. Menthol predicted increased total cotinine levels (P < 0.05). Shorter time to the first cigarette of the day predicted significantly higher minimum (P < 0.05), maximum (P < 0.05), and total cotinine values (P < 0.05) after controlling for covariates. Negative emotions and social interactions with others were also significantly associated with higher cotinine metrics. There was no significant effect of the nicotine metabolite ratio. CONCLUSIONS: Our findings highlight the variability in nicotine exposure across days among non-daily smokers and point to the role of smoking context in nicotine exposure. The findings suggest the need to develop better assessment methods to determine health and dependence risk and personalized cessation interventions for this heterogeneous and growing group of smokers.


Assuntos
Nicotina , Fumar , Adulto , Cotinina , Humanos , Pessoa de Meia-Idade , Pennsylvania , Fumantes , Fumar/epidemiologia , Estados Unidos/epidemiologia , Adulto Jovem
13.
Chem Res Toxicol ; 33(7): 1791-1797, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32363856

RESUMO

Free radicals and nicotine are components of cigarette smoke that are thought to contribute to the development of smoking-induced diseases. China has the largest number of smokers in the world, yet little is known about the yields of tobacco smoke constituents in different Chinese brands of cigarettes. In this study, gas-phase and particulate-phase free radicals as well as nicotine yields were quantified in mainstream cigarette smoke from five popular Chinese brands and two research cigarettes (3R4F and 1R6F). Mainstream smoke was generated under International Organization of Standardization (ISO) and Canadian Intense (CI) smoking regimens using a linear smoking machine. Levels of free radicals and nicotine were measured by electron paramagnetic resonance spectroscopy (EPR) and gas chromatography with flame-ionization detection, respectively. Under the ISO puffing regimen, Chinese brand cigarettes produced an average of 3.0 ± 1.2 nmol/cig gas-phase radicals, 118 ± 44.7 pmol/cig particulate-phase radicals, and 0.6 ± 0.2 mg/cig nicotine. Under the CI puffing regimen, Chinese brand cigarettes produced an average of 5.6 ± 1.2 nmol/cig gas-phase radicals, 282 ± 92.1 pmol/cig particulate-phase radicals, and 2.1 ± 0.4 mg/cig nicotine. Overall, both gas- and particulate-phase free radicals were substantially lower compared to the research cigarettes under both regimens, whereas no significant differences were observed for nicotine levels. When Chinese brands were compared, the highest free radical and nicotine yields were found in "LL" and "BS" brands, while lowest levels were found in "YY". These results suggested that the lower radical delivery by Chinese cigarettes compared to United States reference cigarettes may be associated with reductions in oxidant-related harm.


Assuntos
Radicais Livres/análise , Nicotiana , Nicotina/análise , Fumaça/análise , China , Produtos do Tabaco , Fumar Tabaco
14.
BMC Genet ; 21(1): 72, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32646377

RESUMO

BACKGROUND: RNA-sequencing was performed to explore the bovine liver transcriptomes of Holstein cows to detect potential functional genes related to lactation and milk composition traits in dairy cattle. The bovine transcriptomes of the nine liver samples from three Holstein cows during dry period (50-d prepartum), early lactation (10-d postpartum), and peak of lactation (60-d postpartum) were sequenced using the Illumina HiSeq 2500 platform. RESULTS: A total of 204, 147 and 81 differentially expressed genes (DEGs, p < 0.05, false discovery rate q < 0.05) were detected in early lactation vs. dry period, peak of lactation vs. dry period, and peak of lactation vs. early lactation comparison groups, respectively. Gene ontology and KEGG pathway analysis showed that these DEGs were significantly enriched in specific biological processes related to metabolic and biosynthetic and signaling pathways of PPAR, AMPK and p53 (p < 0.05). Ten genes were identified as promising candidates affecting milk yield, milk protein and fat traits in dairy cattle by using an integrated analysis of differential gene expression, previously reported quantitative trait loci (QTL), data from genome-wide association studies (GWAS), and biological function information. These genes were APOC2, PPP1R3B, PKLR, ODC1, DUSP1, LMNA, GALE, ANGPTL4, LPIN1 and CDKN1A. CONCLUSION: This study explored the complexity of the liver transcriptome across three lactation periods in dairy cattle by performing RNA sequencing. Integrated analysis of DEGs and reported QTL and GWAS data allowed us to find ten key candidate genes influencing milk production traits.


Assuntos
Lactação/genética , Leite/química , Transcriptoma , Animais , Bovinos , Feminino , Estudos de Associação Genética/veterinária , Fígado/metabolismo , Proteínas do Leite/análise , Locos de Características Quantitativas , Análise de Sequência de RNA
15.
Nutr Cancer ; 72(3): 451-459, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31298929

RESUMO

Objective: Chronic Chemotherapy-Induced Peripheral Neuropathy (CIPN) is highly prevalent among colorectal cancer (CRC) patients. Ergothioneine (ET) - a dietary antioxidant -protected against CIPN in experimental models, but human studies are lacking. We explored whether whole blood ET levels were associated with chronic peripheral neuropathy among CRC patients who had completed chemotherapy.Methods: At diagnosis, median ET-concentration in whole blood of 159 CRC patients was 10.2 µg/ml (7.2-15.8). Patients completed questionnaires on peripheral neuropathy 6 months after completion of chemotherapy. We calculated prevalence ratios (PR) to assess associations of ET-concentrations and prevalence of peripheral neuropathy and used linear regression to assess associations with severity of peripheral neuropathy.Results: Prevalence of total and sensory peripheral neuropathy were both 81%. Higher ET-concentrations tended to be associated with lower prevalence of total and sensory peripheral neuropathy, but not statistically significant (highest versus lowest tertile of ET: PR = 0.93(0.78, 1.11) for total neuropathy, and PR = 0.84(0.70, 1.02) for sensory neuropathy). ET-concentrations were not associated with severity of neuropathy.Conclusion: Statistically significant associations were not observed, possibly because of limited sample size. Although data may putatively suggest higher levels of ET to be associated with a lower prevalence of neuropathy, analyses should be repeated in larger populations with larger variability in ET-concentrations.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Ergotioneína/sangue , Doenças do Sistema Nervoso Periférico/epidemiologia , Idoso , Antineoplásicos/uso terapêutico , Antioxidantes/uso terapêutico , Neoplasias Colorretais/sangue , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Prevalência , Qualidade de Vida , Índice de Gravidade de Doença , Inquéritos e Questionários
16.
Inorg Chem ; 59(24): 18131-18140, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33301306

RESUMO

The complete removal of tetracycline residuals under visible light still is a challenging task because of their robust ring structure. To tackle this issue, we explore a novel Bi2O3-sensitized TiO2 visible-light photocatalyst by combining p-n heterojunction with hollow structure. The hollow TiO2/Bi2O3 photocatalyst manifests excellent photocatalytic performance and recyclability toward the complete degradation (100%) of antibiotics under visible light (λ > 420 nm) because of the synergistic effect of p-n heterojunction and hollow structure, successfully overcoming the challenge of the incomplete removal of antibiotics over almost all of the reported visible-light photocatalysts. Additionally, the effects of inorganic ions, pH value, water matrix, and outdoor light on the degradation of tetracyclines were investigated with many details. Notably, the degradation pathways and mechanism of tetracycline were revealed according to trapping experiments, HPLC-MS, and photoelectrochemical characterizations. Therefore, this work provides a new insight into developing visible-light photocatalysts with excellent photocatalytic performances for the complete removal of other refractory contaminants.

17.
Nanotechnology ; 31(27): 275401, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32163942

RESUMO

Although TiO2 is widely used as a promising electrode material for supercapacitors, its potential application suffers from a critical limitation due to its poor electrical conductivity and low rate capability. Here, we report a cost-effective hydrothermal strategy to design and construct a novel 'single-crystal-like' C-doped TiO2 electrode material. The as-synthesized electrode material combines the advantages of TiO2, 'single-crystal-like' features and carbon doping, considerably improving the electrical conductivity of TiO2. The electrochemical measurements demonstrate that the C-doped TiO2 material presents an excellent specific capacitance (449.8 F g-1 at 1 A g-1), which approaches six times more than the value (77.3 F g-1 at 1 A g-1) of P25 electrodes, and far beyond the value of many previously reported TiO2 electrodes. Therefore, this work explores a new method to design high performance electrochemical TiO2 electrode materials by incorporating other dopants into the TiO2 lattice.

18.
Nicotine Tob Res ; 22(2): 273-279, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30892637

RESUMO

INTRODUCTION: Spectrum research cigarettes have been developed with varying nicotine content for use in studies evaluating the effects of a regulatory policy reducing the permissible nicotine content in cigarettes. This study aimed to characterize the nicotine pharmacokinetic profile of Spectrum cigarettes. METHODS: Twelve daily smokers attended four sessions and had blood nicotine, exhaled carbon monoxide, and subjective effects measured before and after smoking either a single cigarette of their preferred brand or high (10.9 mg/cigarette), medium (3.2 mg/cigarette), or low (0.2 mg/cigarette) nicotine content Spectrum research cigarettes, in a double-blind design with order counterbalanced. RESULTS: The boost in blood nicotine concentration was dose-dependent, with a boost of 0.3, 3.9, and 17.3 ng/mL for low-, medium-, and high-nicotine content Spectrum cigarettes. The high dose Spectrum had a similar nicotine boost to the "preferred brand" cigarettes (19 ng/mL). Subjects took longer puffs on the low nicotine cigarettes, but smoked these cigarettes faster than other cigarette types. High nicotine Spectrum cigarettes reduced the urge to smoke more than other cigarette types. CONCLUSIONS: This study shows that Spectrum research cigarettes produce blood nicotine absorption in a dose-dependent manner, and therefore, are appropriate for use in studies of nicotine reduction in cigarettes. IMPLICATIONS: This is the first study to determine the pharmacokinetic profile of Spectrum reduced nicotine content research cigarettes following an overnight abstinence. These data could provide evidence to regulatory agencies about the effects of reduced nicotine cigarettes when considering regulations on tobacco reduction.


Assuntos
Fumar Cigarros/sangue , Nicotina/administração & dosagem , Nicotina/sangue , Abandono do Hábito de Fumar/métodos , Produtos do Tabaco , Adolescente , Adulto , Monóxido de Carbono/análise , Fumar Cigarros/psicologia , Fumar Cigarros/tendências , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Abandono do Hábito de Fumar/psicologia , Adulto Jovem
19.
Asian-Australas J Anim Sci ; 33(11): 1725-1731, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32106650

RESUMO

OBJECTIVE: An initial RNA-Sequencing study revealed that UDP-galactose-4-epimerase (GALE) was one of the most promising candidates for milk protein concentration in Chinese Holstein cattle. This enzyme catalyzes the interconversion of UDP-galactose and UDP-glucose, an important step in galactose catabolism. To further validate the genetic effect of GALE on milk protein traits, genetic variations were identified, and genotypes-phenotypes associations were performed. METHODS: The entire coding region and the 5'-regulatory region (5'-UTR) of GALE were re-sequenced using pooled DNA of 17 unrelated sires. Association studies for five milk production traits were performed using a mixed linear animal model with a population encompassing 1,027 Chinese Holstein cows. RESULTS: A total of three variants in GALE were identified, including two novel variants (g.2114 A>G and g.2037 G>A) in the 5'-UTR and one previously reported variant (g.3836 G>C) in an intron. All three single nucleotide polymorphisms (SNPs) were associated with milk yield (p<0.0001), fat yield (p = 0.0006 to <0.0001), protein yield (p = 0.0232 to <0.0001) and protein percentage (p<0.0001), while no significant associations were detected between the SNPs and fat percentage. A strong linkage disequilibrium (D' = 0.96 to 1.00) was observed among all three SNPs, and a 5 Kb haplotype block involving three main haplotypes with GAG, AGC, and AGG was formed. The results of haplotype association analyses were consistent with the results of single locus association analysis (p<0.0001). The phenotypic variance ratio above 3.00% was observed for milk protein yield that was explained by SNP-g.3836G >C. CONCLUSION: Overall, our findings provided new insights into the polymorphic variations in bovine GALE gene and their associations with milk protein concentration. The data indicate their potential uses for marker-assisted breeding or genetic selection schemes.

20.
Proteomics ; 19(12): e1800387, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30903674

RESUMO

In this study, the proteomes of liver tissues are investigated in three periods of the lactation cycle of Holstein cows by using isobaric tag for relative and absolute quantification (iTRAQ) technique to obtain liver proteome and identify functional proteins/genes involved in milk synthesis in dairy cattle. Based on iTRAQ analysis, 3252 proteins are detected in the liver tissues (false discovery rate ≤0.01). Thirty-two differently expressed proteins (DEPs) are identified during the three periods by p-value <0.05 and fold change (FC) ≥2 or ≤0.5, and 183 DEPs based on p-value <0.05 and FC ≥1.5 or ≤0.67. In addition, 905 DEPs are obtained across the three periods by p-value <0.05 and FC ≥1.2, or ≤0.83, and the subsequent GO and KEGG pathway functional analysis indicate that 73 DEPs are significantly enriched into the metabolic terms and pathways involved in milk synthesis such as citrate cycle, fatty acid, starch and sucrose metabolism, and mTOR and PPAR signaling pathways. Further, 41 out of 73 DEPs are identified near to both the peak locations of the reported quantitative trait locus and significant single nucleotide polymorphisms that associate with milk yield and composition traits. In addition, the 41 DEPs are analyzed with the previous liver transcriptome data that used the same samples as this study, and considered nine proteins/genes-ALDH18A1, APOA4, CYP7A1, HADHB, PRKACA, IDH2, LDHA, LDHB, and MAT2A-to be the promising candidates for milk fat, protein, and lactose synthesis in dairy cattle. This study provides a new vision for identifying the potential critical genes associated with milk synthesis of dairy cattle.


Assuntos
Fígado/metabolismo , Proteínas do Leite/genética , Leite/metabolismo , Proteoma/genética , Animais , Bovinos , Gorduras/metabolismo , Regulação da Expressão Gênica/genética , Lactose/genética , Lactose/metabolismo , Leite/química , Polimorfismo de Nucleotídeo Único/genética , Proteômica/métodos , Transcriptoma/genética
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