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1.
BMC Genomics ; 25(1): 249, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448842

RESUMEN

BACKGROUND: Iron plays a crucial role in the growth of Mycobacterium tuberculosis (M. tuberculosis). However, the precise regulatory mechanism governing this system requires further elucidation. Additionally, limited studies have examined the impact of gene mutations related to iron on the transmission of M. tuberculosis globally. This research aims to investigate the correlation between mutations in iron-related genes and the worldwide transmission of M. tuberculosis. RESULTS: A total of 13,532 isolates of M. tuberculosis were included in this study. Among them, 6,104 (45.11%) were identified as genomic clustered isolates, while 8,395 (62.04%) were classified as genomic clade isolates. Our results showed that a total of 12 single nucleotide polymorphisms (SNPs) showed a positive correlation with clustering, such as Rv1469 (ctpD, C758T), Rv3703c (etgB, G1122T), and Rv3743c (ctpJ, G676C). Additionally, seven SNPs, including Rv0104 (T167G, T478G), Rv0211 (pckA, A302C), Rv0283 (eccB3, C423T), Rv1436 (gap, G654T), ctpD C758T, and etgB C578A, demonstrated a positive correlation with transmission clades across different countries. Notably, our findings highlighted the positive association of Rv0104 T167G, pckA A302C, eccB3 C423T, ctpD C758T, and etgB C578A with transmission clades across diverse regions. Furthermore, our analysis identified 78 SNPs that exhibited significant associations with clade size. CONCLUSIONS: Our study reveals the link between iron-related gene SNPs and M. tuberculosis transmission, offering insights into crucial factors influencing the pathogenicity of the disease. This research holds promise for targeted strategies in prevention and treatment, advancing research and interventions in this field.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Mycobacterium tuberculosis/genética , Secuenciación Completa del Genoma , Hierro , Mutación , Tuberculosis/genética
2.
BMC Genomics ; 25(1): 810, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39198760

RESUMEN

BACKGROUND: The respiratory chain plays a key role in the growth of Mycobacterium tuberculosis complex (MTBC). However, the exact regulatory mechanisms of this system still need to be elucidated, and only a few studies have investigated the impact of genetic mutations within the respiratory chain on MTBC transmission. This study aims to explore the impact of respiratory chain gene mutations on the global spread of MTBC. RESULTS: A total of 13,402 isolates of MTBC were included in this study. The majority of the isolates (n = 6,382, 47.62%) belonged to lineage 4, followed by lineage 2 (n = 5,123, 38.23%). Our findings revealed significant associations between Single Nucleotide Polymorphisms (SNPs) of specific genes and transmission clusters. These SNPs include Rv0087 (hycE, G178T), Rv1307 (atpH, C650T), Rv2195 (qcrA, G181C), Rv2196 (qcrB, G1250T), Rv3145 (nuoA, C35T), Rv3149 (nuoE, G121C), Rv3150 (nuoF, G700A), Rv3151 (nuoG, A1810G), Rv3152 (nuoH, G493A), and Rv3157 (nuoM, A1243G). Furthermore, our results showed that the SNPs of atpH C73G, atpA G271C, qcrA G181C, nuoJ G115A, nuoM G772A, and nuoN G1084T were positively correlated with cross-country transmission clades and cross-regional transmission clades. CONCLUSIONS: Our study uncovered an association between mutations in respiratory chain genes and the transmission of MTBC. This important finding provides new insights for future research and will help to further explore new mechanisms of MTBC pathogenicity. By uncovering this association, we gain a more complete understanding of the processes by which MTBC increases virulence and spread, providing potential targets and strategies for preventing and treating tuberculosis.


Asunto(s)
Mutación , Mycobacterium tuberculosis , Polimorfismo de Nucleótido Simple , Tuberculosis , Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Tuberculosis/genética , Tuberculosis/transmisión , Humanos , Transporte de Electrón/genética , Proteínas Bacterianas/genética
3.
J Am Chem Soc ; 146(12): 8425-8434, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38488481

RESUMEN

The precise design of catalytic metal centers with multiple chemical states to facilitate sophisticated reactions involving multimolecular activation is highly desirable but challenging. Herein, we report an ordered macroporous catalyst with heterovalent metal pair (HMP) sites comprising CuII-CuI on the basis of a microporous metal-organic framework (MOF) system. This macroporous HMP catalyst with proximity heterovalent dual copper sites, whose distance is controlled to ∼2.6 Å, on macropore surface exhibits a co-activation behavior of ethanol at CuII and alkyne at CuI, and avoids microporous restriction, thereby promoting additive-free alkyne hydroboration reaction. The desired yield enhances dramatically compared with the pristine MOF and ordered macroporous MOF both with solely isovalent CuII-CuII sites. Density functional theory calculations reveal that the Cu-HMP sites can stabilize the Bpin-CuII-CuI-alkyne intermediate and facilitate C-B bond formation, resulting in a smooth alkyne hydroboration process. This work provides new perspectives to design multimolecular activation catalysts for sophisticated matter transformations.

4.
BMC Microbiol ; 24(1): 206, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858614

RESUMEN

OBJECTIVE: This study aims to examine the impact of PE/PPE gene mutations on the transmission of Mycobacterium tuberculosis (M. tuberculosis) in China. METHODS: We collected the whole genome sequencing (WGS) data of 3202 M. tuberculosis isolates in China from 2007 to 2018 and investigated the clustering of strains from different lineages. To evaluate the potential role of PE/PPE gene mutations in the dissemination of the pathogen, we employed homoplastic analysis to detect homoplastic single nucleotide polymorphisms (SNPs) within these gene regions. Subsequently, logistic regression analysis was conducted to analyze the statistical association. RESULTS: Based on nationwide M. tuberculosis WGS data, it has been observed that the majority of the M. tuberculosis burden in China is caused by lineage 2 strains, followed by lineage 4. Lineage 2 exhibited a higher number of transmission clusters, totaling 446 clusters, of which 77 were cross-regional clusters. Conversely, there were only 52 transmission clusters in lineage 4, of which 9 were cross-regional clusters. In the analysis of lineage 2 isolates, regression results showed that 4 specific gene mutations, PE4 (position 190,394; c.46G > A), PE_PGRS10 (839,194; c.744 A > G), PE16 (1,607,005; c.620T > G) and PE_PGRS44 (2,921,883; c.333 C > A), were significantly associated with the transmission of M. tuberculosis. Mutations of PE_PGRS10 (839,334; c.884 A > G), PE_PGRS11 (847,613; c.1455G > C), PE_PGRS47 (3,054,724; c.811 A > G) and PPE66 (4,189,930; c.303G > C) exhibited significant associations with the cross-regional clusters. A total of 13 mutation positions showed a positive correlation with clustering size, indicating a positive association. For lineage 4 strains, no mutations were found to enhance transmission, but 2 mutation sites were identified as risk factors for cross-regional clusters. These included PE_PGRS4 (338,100; c.974 A > G) and PPE13 (976,897; c.1307 A > C). CONCLUSION: Our results indicate that some PE/PPE gene mutations can increase the risk of M. tuberculosis transmission, which might provide a basis for controlling the spread of tuberculosis.


Asunto(s)
Mutación , Mycobacterium tuberculosis , Polimorfismo de Nucleótido Simple , Tuberculosis , Secuenciación Completa del Genoma , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , China/epidemiología , Humanos , Tuberculosis/transmisión , Tuberculosis/microbiología , Tuberculosis/epidemiología , Genoma Bacteriano , Femenino , Masculino , Proteínas Bacterianas/genética , Adulto
5.
BMC Infect Dis ; 24(1): 1250, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39501228

RESUMEN

BACKGROUND: The emergence of Multidrug-Resistant Tuberculosis (MDR-TB) poses a significant threat to global tuberculosis control efforts. This study aimed to examine the influence of mutations in Toxin-Antitoxin system genes on the global transmission of MDR-TB caused by Mycobacterium tuberculosis (M. tuberculosis). METHODS: Whole-genome sequencing was conducted on 13,518 M. tuberculosis isolates. Genes of the Toxin-Antitoxin system were obtained from the National Center for Biotechnology Information (NCBI) Gene database. Techniques such as Random Forest, Gradient Boosting Decision Tree, and Generalized Linear Mixed Models were employed to identify mutation sites in Toxin-Antitoxin system-related genes that facilitated the transmission of MDR-TB. RESULTS: 4,066 (30.08%) were identified as MDR-TB strains of all analyzed isolates. We found significant associations between specific gene mutations and MDR-TB transmission clusters including mutations in Rv0298 (G213A), Rv1959c (parE1, C88T), Rv1960c (parD1, C134T), Rv1991A (maze, G156A), Rv2547 (vapB, C54G), Rv2862A (vapB23, T2C), and Rv3385c (vapB46, G70A). Additionally, several gene mutations associated with MDR-TB transmission clades such as Rv1956 (higA, G445T), Rv1960c (parD1, C134T), and Rv1962A (vapB35, G99A) were noted. Certain gene mutations including vapB35 (G99A), higA (G445T), and parD1 (C134T) correlated with cross-regional transmission clades. CONCLUSION: This study highlights the significant association between specific gene mutations in the Toxin-Antitoxin system and the global transmission of MDR-TB, providing valuable insights for developing targeted interventions to control MDR-TB.


Asunto(s)
Mutación , Mycobacterium tuberculosis , Sistemas Toxina-Antitoxina , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/genética , Sistemas Toxina-Antitoxina/genética , Humanos , Mycobacterium tuberculosis/genética , Secuenciación Completa del Genoma , Proteínas Bacterianas/genética
6.
BMC Genomics ; 24(1): 718, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017383

RESUMEN

BACKGROUND: Two-component systems (TCSs) assume a pivotal function in Mycobacterium tuberculosis (M.tuberculosis) growth. However, the exact regulatory mechanism of this system needs to be elucidated, and only a few studies have investigated the effect of gene mutations within TCSs on M.tuberculosis transmission. This research explored the relationship between TCSs gene mutation and the global transmission of (M.tuberculosis). RESULTS: A total of 13531 M.tuberculosis strains were enrolled in the study. Most of the M.tuberculosis strains belonged to lineage4 (n=6497,48.0%), followed by lineage2 (n=5136,38.0%). Our results showed that a total of 36 single nucleotide polymorphisms (SNPs) were positively correlated with clustering of lineage2, such as Rv0758 (phoR, C820G), Rv1747(T1102C), and Rv1057(C1168T). A total of 30 SNPs showed positive correlation with clustering of lineage4, such as phoR(C182A, C1184G, C662T, T758G), Rv3764c (tcrY, G1151T), and Rv1747 C20T. A total of 19 SNPs were positively correlated with cross-country transmission of lineage2, such as phoR A575C, Rv1028c (kdpD, G383T, G1246C), and Rv1057 G817T. A total of 41 SNPs were positively correlated with cross-country transmission of lineage4, such as phoR(T758G, T327G, C284G), kdpD(G1755A, G625C), Rv1057 C980T, and Rv1747 T373G. CONCLUSIONS: Our study identified that SNPs in genes of two-component systems were related to the transmission of M. tuberculosis. This finding adds another layer of complexity to M. tuberculosis virulence and provides insight into future research that will help to elucidate a novel mechanism of M. tuberculosis pathogenicity.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Mutación , Secuenciación Completa del Genoma , Tuberculosis/genética , Tuberculosis/microbiología , Polimorfismo de Nucleótido Simple , Genoma Bacteriano
7.
BMC Microbiol ; 23(1): 379, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38041005

RESUMEN

BACKGROUND: Fatty acid metabolism greatly promotes the virulence and pathogenicity of Mycobacterium tuberculosis (M.tb). However, the regulatory mechanism of fatty acid metabolism in M.tb remains to be elucidated, and limited evidence about the effects of gene mutations in fatty acid metabolism on the transmission of M.tb was reported. RESULTS: Overall, a total of 3193 M.tb isolates were included in the study, of which 1596 (50%) were genomic clustered isolates. Most of the tuberculosis isolates belonged to lineage2(n = 2744,85.93%), followed by lineage4(n = 439,13.75%) and lineage3(n = 10,0.31%).Regression results showed that the mutations of gca (136,605, 317G > C, Arg106Pro; OR, 22.144; 95% CI, 2.591-189.272), ogt(1,477,346, 286G > C ,Gly96Arg; OR, 3.893; 95%CI, 1.432-10.583), and rpsA (1,834,776, 1235 C > T, Ala412Val; OR, 3.674; 95% CI, 1.217-11.091) were significantly associated with clustering; mutations in gca and rpsA were also significantly associated with clustering of lineage2. Mutation in arsA(3,001,498, 885 C > G, Thr295Thr; OR, 6.278; 95% CI, 2.508-15.711) was significantly associated with cross-regional clusters. We also found that 20 mutation sites were positively correlated with cluster size, while 11 fatty acid mutation sites were negatively correlated with cluster size. CONCLUSION: Our research results suggested that mutations in genes related to fatty acid metabolism were related to the transmission of M.tb. This research could help in the future control of the transmission of M.tb.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Antituberculosos/farmacología , Tuberculosis/microbiología , Secuenciación Completa del Genoma , Mutación , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
8.
J Org Chem ; 88(15): 10670-10681, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37467204

RESUMEN

The construction of multisubstituted ß-pyrrolinones from simple starting materials remains a great challenge. Recently, a novel Cu(I)-catalyzed [2 + 2 + 1] cycloaddition reaction was developed for rapid access to fully substituted ß-pyrrolinones, which are difficult to synthesize through traditional methods as this approach may involve unusual C-nucleophilic addition of enamines and umpolung of imines. Elucidating the reaction mechanism may inspire the development of new methodologies via the unusual C-nucleophilic addition of enamines and imines. However, the reaction mechanism is still unclear because none of the intermediates was observed during the reaction process. In this work, we employed theoretical and computational chemistry to investigate the possible pathway. Finally, the calculated results indicate that ketene formed by the Wolff rearrangement of α-diazo-ß-ketoester reacts with enamine formed by the addition of alkynes and amine, affording the five-membered azaheterocycle, and this process involves the formation of a six-membered ring intermediate and sequential isomerization, and the further dehydrogenation needs to be assisted with solvent MeNO2.

9.
Nicotine Tob Res ; 25(8): 1481-1488, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37099744

RESUMEN

INTRODUCTION: Cigarette smoking continues to pose a threat to public health. Identifying individual risk factors for smoking initiation is essential to further mitigate this epidemic. To the best of our knowledge, no study today has used machine learning (ML) techniques to automatically uncover informative predictors of smoking onset among adults using the Population Assessment of Tobacco and Health (PATH) study. AIMS AND METHODS: In this work, we employed random forest paired with Recursive Feature Elimination to identify relevant PATH variables that predict smoking initiation among adults who have never smoked at baseline between two consecutive PATH waves. We included all potentially informative baseline variables in wave 1 (wave 4) to predict past 30-day smoking status in wave 2 (wave 5). Using the first and most recent pairs of PATH waves was found sufficient to identify the key risk factors of smoking initiation and test their robustness over time. The eXtreme Gradient Boosting method was employed to test the quality of these selected variables. RESULTS: As a result, classification models suggested about 60 informative PATH variables among many candidate variables in each baseline wave. With these selected predictors, the resulting models have a high discriminatory power with the area under the specificity-sensitivity curves of around 80%. We examined the chosen variables and discovered important features. Across the considered waves, two factors, (1) BMI, and (2) dental and oral health status, robustly appeared as important predictors of smoking initiation, besides other well-established predictors. CONCLUSIONS: Our work demonstrates that ML methods are useful to predict smoking initiation with high accuracy, identifying novel smoking initiation predictors, and to enhance our understanding of tobacco use behaviors. IMPLICATIONS: Understanding individual risk factors for smoking initiation is essential to prevent smoking initiation. With this methodology, a set of the most informative predictors of smoking onset in the PATH data were identified. Besides reconfirming well-known risk factors, the findings suggested additional predictors of smoking initiation that have been overlooked in previous work. More studies that focus on the newly discovered factors (BMI and dental and oral health status,) are needed to confirm their predictive power against the onset of smoking as well as determine the underlying mechanisms.


Asunto(s)
Fumar Cigarrillos , Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Adulto , Humanos , Estudios Longitudinales , Uso de Tabaco/epidemiología , Fumar Cigarrillos/epidemiología , Factores de Riesgo
10.
Nicotine Tob Res ; 25(3): 486-497, 2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36073731

RESUMEN

BACKGROUND: We model the potential impact of relaxing current nicotine vaping product (NVP) restrictions on public health in Australia. AIMS AND METHODS: A Restricted NVP Scenario was first developed to project current smoking and vaping rates, where a U.S. smoking model was calibrated to recent Australian trends. To model less restrictive NVP policies, a Permissive NVP Scenario applied rates of switching from smoking to vaping, initiation into NVP and cigarette use, and cessation from smoking and vaping based on U.S. trends. The model measures vaping risk relative to the excess mortality rate of smoking. The public health impacts are measured as the difference between smoking- and vaping-attributable deaths (SVADs) and life years lost (LYLs) in the Restricted and Permissive NVP Scenarios. Sensitivity analysis is conducted regarding the NVP excess risk and other factors. RESULTS: Assuming an NVP excess risk of 5% that of smoking, 104.2 thousand SVADs (7.7% reduction) and 2.05 million LYLs (17.3% reduction) are averted during 2017-2080 in the Permissive NVP Scenario compared to the Restricted NVP Scenario. Assuming 40% NVP excess risk, 70 thousand SVADs and 1.2 million LYLs are averted. The impact is sensitive to the rate at which smokers switch to NVPs and quit smoking, and relatively insensitive to the smoking initiation and NVP initiation and cessation rates. CONCLUSIONS: The model suggests the potential for public health gains to be achieved by relaxing NVP access regulations. However, the model would benefit from better information regarding the impact of NVPs on smoking under a relaxation of current restrictions. IMPLICATIONS: Australia has implemented a strong array of cigarette-oriented policies, but has restricted access to NVPs. The Smoking and Vaping Model offers a framework for modeling hypothetical policy scenarios. The Australian model shows the potential for public health gains by maintaining cigarette-oriented policies while relaxing the current restrictive NVP policy. Modeling results under a permissive NVP policy are particularly sensitive to the estimated rates of smoking cessation and switching to vaping, which are not well established and will likely depend on past and future cigarette-oriented policies and the specific NVP policies implemented in Australia.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Cese del Hábito de Fumar , Vapeo , Humanos , Vapeo/epidemiología , Nicotina , Australia/epidemiología , Fumar
11.
Phys Chem Chem Phys ; 25(33): 22304-22309, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37578133

RESUMEN

Hetero-bimetallic organic compounds have great potential for the development of new nonlinear optical (NLO) materials, due to their large first hyperpolarizabilities (ßtot). Herein, due to their versatility and ease of functionalization, the second-order NLO properties of a series of linked sandwich metallacarboranes were studied by changing their linkages to different organic groups. The calculated ßtot values suggest that the NLO response was significantly enhanced when an alkenyl group of appropriate length was inserted into the B-B or C-C bonds connecting the metallacarborane units. Time-dependent density-functional theory was used to explain how the connection modes and the use of organic groups as linkers can give rise to different types of charge transfer. Moreover, the NLO responses of the redox states (+1 and -1) were calculated, with the aim of investigating the NLO switching effects of the -1/0/+1 states. Comparison of the ßtot values for the different states shows that the studied linked sandwich metallacarboranes could serve as three-state NLO molecular switches stimulated by redox processes.

12.
Phys Chem Chem Phys ; 25(10): 7436-7444, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36847782

RESUMEN

As an emerging two-dimensional (2D) material, the TiB4 monolayer possesses intrinsic advantages in electrochemical applications owing to its graphene-like structure and metallic characteristics. In this work, we performed density functional calculations to investigate the electrochemical properties of the TiB4 monolayer as an anode material for Li/Na/K ion batteries and as an electrocatalyst for the nitrogen reduction reaction (NRR). Our investigation reveals that Li/Na/K ions could be steadily adsorbed on the TiB4 monolayer with moderate adsorption energies, and tended to diffuse along two adjacent C-sites with lower energy barriers (0.231/0.094/0.067 eV for Li/Na/K ions) compared to the currently reported transition-metal boride monolayers. Furthermore, a N2 molecule can be spontaneously captured by the TiB4 monolayer with a negative Gibbs free energy (-0.925 eV and -0.326 eV for end-on and side-on adsorptions, respectively), hence provoking a conversion into NH3 along the most efficient reaction pathway (i.e., N2* → N2H* → HNNH* → H2NNH* → H3NNH* → NH* → NH2* → NH3*). In the hydrogenation process, the TiB4 monolayer exhibits much higher catalytic activity for the NRR as compared with other electrocatalysts, which should be attributed to the spontaneous achievement (ΔG < 0) at all hydrogenation reaction steps except the potential-determining step. Moreover, the TiB4 monolayer exhibits higher selectivity toward the NRR than the hydrogen evolution reaction. Our work advances the mechanistic understanding on the electrochemical properties of the TiB4 monolayer as an anode material for metal-ion batteries and as a NRR electrocatalyst, and provides significant guidance for developing high-performance multifunctional 2D materials.

13.
Phys Chem Chem Phys ; 25(27): 18266-18274, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37395285

RESUMEN

High-energy-density fuel cells and metal-air batteries are difficult to commercialize on a large scale mainly because of the sluggish oxygen reduction reaction (ORR) at the cathode. Hence, the development of high-efficiency and low-cost electrocatalysts as Pt substitutes for the ORR is of significance for the mass applications of these devices. In this work, we thoroughly investigated the structural and catalytic properties of NiPd co-doped N-coordinated graphene (denoted as NiPdN6-G) as an ORR electrocatalyst by using density-functional theory (DFT) calculations. Our results show that NiPdN6-G is structurally and thermodynamically stable. Furthermore, we explored all the possible paths and intermediates of the ORR, and identified the preferable active sites and the most stable adsorption configurations of the intermediates and transition states. In general, there are 15 possible reaction paths, of which 8 paths have lower energy barriers than pure Pt, and the maximum energy barrier and overpotential of the ORR for the optimal path are only 0.14 eV and 0.37 V, respectively. This work demonstrates that NiPdN6-G should be a promising candidate for substituting Pt and Pt-based catalysts for the ORR in energy conversion and storage devices.

14.
Tob Control ; 32(e1): e37-e44, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34475258

RESUMEN

INTRODUCTION: The US Food and Drug Administration most recently announced its intention to ban menthol cigarettes and cigars nationwide in April 2021. Implementation of the ban will require evidence that it would improve public health. This paper simulates the potential public health impact of a ban on menthol in cigarettes and cigars through its impacts on smoking initiation, smoking cessation and switching to nicotine vaping products (NVPs). METHODS: After calibrating an established US simulation model to reflect recent use trends in cigarette and NVP use, we extended the model to incorporate menthol and non-menthol cigarette use under a status quo scenario. Applying estimates from a recent expert elicitation on the behavioural impacts of a menthol ban, we developed a menthol ban scenario with the ban starting in 2021. We estimated the public health impact as the difference between smoking and vaping-attributable deaths and life-years lost in the status quo scenario and the menthol ban scenario from 2021 to 2060. RESULTS: As a result of the ban, overall smoking was estimated to decline by 15% as early as 2026 due to menthol smokers quitting both NVP and combustible use or switching to NVPs. These transitions are projected to reduce cumulative smoking and vaping-attributable deaths from 2021 to 2060 by 5% (650 000 in total) and reduce life-years lost by 8.8% (11.3 million). Sensitivity analyses showed appreciable public health benefits across different parameter specifications. CONCLUSIONS AND RELEVANCE: Our findings strongly support the implementation of a ban on menthol in cigarettes and cigars.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Cese del Hábito de Fumar , Productos de Tabaco , Vapeo , Humanos , Mentol , Salud Pública , Fumar/epidemiología , Nicotina
15.
BMC Public Health ; 23(1): 2299, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37990171

RESUMEN

BACKGROUND: Simulation models play an increasingly important role in tobacco control. Models examining the impact of nicotine vaping products (NVPs) and smoking tend to be highly specialized and inaccessible. We present the Smoking and Vaping Model (SAVM),a user-friendly cohort-based simulation model, adaptable to any country, that projects the public health impact of smokers switching to NVPs. METHODS: SAVM compares two scenarios. The No-NVP scenario projects smoking rates in the absence of NVPs using population projections, deaths rates, life expectancy, and smoking prevalence. The NVP scenario models vaping prevalence and its impact on smoking once NVPs became popular. NVP use impact is estimated as the difference in smoking- and vaping-attributable deaths (SVADs) and life-years lost (LYLs) between the No-NVP and NVP scenarios. We illustrate SAVM's adaptation to the German adult ages 18+ population, the Germany-SAVM by adjusting the model using population, mortality, smoking and NVP use data. RESULTS: Assuming that the excess NVP mortality risk is 5% that of smoking, Germany-SAVM projected 4.7 million LYLs and almost 300,000 SVADs averted associated with NVP use from 2012 to 2060. Increasing the excess NVP mortality risk to 40% with other rates constant resulted in averted 2.8 million LYLs and 200,000 SVADs during the same period. CONCLUSIONS: SAVM enables non-modelers, policymakers, and other stakeholders to analyze the potential population health effects of NVP use and public health interventions.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Cese del Hábito de Fumar , Vapeo , Adulto , Humanos , Vapeo/epidemiología , Nicotina , Fumar/epidemiología , Fumar Tabaco
16.
Ecotoxicol Environ Saf ; 252: 114597, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36739738

RESUMEN

Maternal exposure to antibiotics existing in the environment is a predisposing factor for developmental malformation with metabolic disorders in offspring. In this study, female zebrafish (3 months) were exposed to 0.05 mg/L and 0.5 mg/L florfenicol (FF) for 28 days. After pairing and spawning with healthy male fish, F1 embryos were collected and developed to 5 d post-fertilization (dpf) in clear water. And the adverse effects on the F1 generation were examined thoroughly. The fecundity of F0 female fish and the hatchability, mortality, and body length of F1 larvae significantly decreased in the treatment group. Meanwhile, multi-malformation types were found in the exposure group, including delayed yolk sac absorption, lack of swim bladder, and spinal curvature. Metabolomic and transcriptomic results revealed alterations in metabolism with dysregulation in tricarboxylase acid cycle, amino acid metabolism, and disordered lipid metabolism with elevated levels of glycerophospholipid and sphingolipid. Accompanying these metabolic derangements, decreased levels of ATP and disordered oxidative-redox state were observed. These results were consistent with the damaged mitochondrial membrane potential and respiratory chain function, suggesting that the developmental toxicity and perturbed metabolic signaling in the F1 generation were related to the mitochondrial injury after exposing F0 female zebrafish to FF. Our findings highlighted the potential toxicity of FF to offspring generations even though they were not directly exposed to environmental contaminants.


Asunto(s)
Tianfenicol , Contaminantes Químicos del Agua , Animales , Masculino , Femenino , Pez Cebra/fisiología , Tianfenicol/toxicidad , Larva , Redes y Vías Metabólicas , Mitocondrias , Contaminantes Químicos del Agua/toxicidad
17.
Plant Dis ; 107(2): 500-513, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35815962

RESUMEN

Leaf spot is a common and serious disease of sweet cherry worldwide and has become a major concern in China. From 2018 to 2020, disease investigations were carried out in Beijing City, Sichuan, Shandong, and Liaoning Provinces in China, and 105 Colletotrichum isolates were obtained from diseased samples. Isolates were identified by morphological characterization coupled with multigene phylogenetic analyses based on six loci (internal transcribed spacer region, glyceraldehyde 3-phosphate dehydrogenase, calmodulin, actin, chitin synthase, and ß-tubulin). A total of 13 Colletotrichum species were identified, namely Colletotrichum aenigma, C. gloeosporioides, C. fructicola, C. siamense, C. temperatum, C. conoides, C. hebeiense, C. sojae, C. plurivorum, C. karsti, C. truncatum, C. incanum, and C. dematium. Among these, C. aenigma (25.7%) was the most prominent species isolated from diseased leaves, followed by C. gloeosporioides (19.0%) and C. fructicola (12.4%). Pathogenicity was tested on detached leaves of cv. 'Tieton' and 'Summit' and young seedlings of cv. 'Brooks' under greenhouse conditions. All 13 species were pathogenic to cherry leaves, and C. aenigma, C. conoides, and C. dematium showed high levels of virulence. Seedlings inoculated with the isolates developed similar symptoms to those seen in the orchards. This study provides the first reports for 11 of the 13 Colletotrichum species on sweet cherry in the world, excluding C. aenigma and C. fructicola. This is the first comprehensive study of Colletotrichum species associated with cherry leaf spot in China, and the results will provide basic knowledge to develop sustainable control measures for cherry leaf spot.


Asunto(s)
Colletotrichum , Prunus avium , Filogenia , Enfermedades de las Plantas , ADN de Hongos , China
18.
J Chem Inf Model ; 62(10): 2398-2408, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35533292

RESUMEN

Global optimization of multicomponent cluster structures is considerably time-consuming due to the existence of a vast number of isomers. In this work, we proposed an improved self-adaptive differential evolution with the neighborhood search (SaNSDE) algorithm and applied it to the global optimization of bimetallic cluster structures. The cross operation was optimized, and an improved basin hopping module was introduced to enhance the searching efficiency of SaNSDE optimization. Taking (PtNi)N (N = 38 or 55) bimetallic clusters as examples, their structures were predicted by using this algorithm. The traditional SaNSDE algorithm was carried out for comparison with the improved SaNSDE algorithm. For all the optimized clusters, the excess energy and the second difference of the energy were calculated to examine their relative stabilities. Meanwhile, the bond order parameters were adopted to quantitatively characterize the cluster structures. The results reveal that the improved SaNSDE algorithm possessed significantly higher searching capability and faster convergence speed than the traditional SaNSDE algorithm. Furthermore, the lowest-energy configurations of (PtNi)38 clusters could be classified as the truncated octahedral and disordered structures. In contrast, all the optimal (PtNi)55 clusters were approximately icosahedral. Our work fully demonstrates the high efficiency of the improved algorithm and advances the development of global optimization algorithms and the structural prediction of multicomponent clusters.

19.
Nicotine Tob Res ; 24(10): 1523-1533, 2022 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-35143678

RESUMEN

INTRODUCTION: Tobacco couponing continues to be part of contemporary tobacco marketing in the United States. We performed a systematic review of the evidence of tobacco product coupon receipt and redemption to inform regulation. AIMS AND METHODS: We searched EMBASE OVID and Medline databases for observational (cross-sectional and longitudinal) studies that examined the prevalence of tobacco coupon receipt and coupon redemption across different subpopulations, as well as studies of the association between coupon receipt and redemption with tobacco initiation and cessation at follow-up. We extracted unadjusted and adjusted odds ratios for the associations between coupon exposure (receipt, redemption) and tobacco use outcomes (initiation, cessation) and assessed each studies' potential risk of bias. RESULTS: Twenty-seven studies met the criteria for inclusion. Of 60 observations extracted, 37 measured coupon receipt, nine measured coupon redemption, eight assessed tobacco use initiation, and six assessed cessation. Tobacco product coupon receipt and redemption tended to be more prevalent among younger adults, women, lower education individuals, members of sexual and gender minorities, and more frequent tobacco users. Coupon receipt at baseline was associated with greater initiation. Coupon receipt and redemption at baseline were associated with lower cessation at follow-up among tobacco users. Results in high-quality studies did not generally differ from all studies. CONCLUSIONS: Tobacco product coupon receipt and redemption are often more prevalent among price-sensitive subpopulations. Most concerning, our results suggest coupon receipt may be associated with higher tobacco initiation and lower tobacco cessation. Couponing thereby increases the toll of tobacco use and could prove to be a viable public health policy intervention point. IMPLICATIONS: A systematic review was conducted of the scientific literature about the receipt, redemption, and effects on tobacco initiation and cessation of tobacco product couponing. This review found that tobacco coupons are more often received by price-sensitive persons and these coupons serve to increase tobacco initiation and decrease tobacco cessation. Policy efforts to address these consequences may help curb tobacco's harms and address health inequities.


Asunto(s)
Nicotiana , Productos de Tabaco , Adulto , Estudios Transversales , Femenino , Humanos , Fumar/epidemiología , Uso de Tabaco/epidemiología , Estados Unidos/epidemiología
20.
Tob Control ; 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35700999

RESUMEN

INTRODUCTION: With the US Food and Drug Administration recently proposing to implement a ban on menthol cigarettes, it is critical to estimate the potential public health effects of such a ban. With high rates of menthol cigarette use and important smoking-related health disparity implications, the impact of the ban on the non-Hispanic black (NHB) population merits strong consideration. METHODS: We apply the previously developed Menthol Smoking and Vaping Model to the NHB population. A status quo scenario is developed using NHB-specific population, smoking and vaping initiation, cessation and death rates. Estimates from a recent expert elicitation on behavioural impacts of a menthol cigarette ban on the NHB population are used to develop a menthol ban scenario implemented in 2021. The public health impacts of the menthol ban are estimated as the difference between smoking and vaping attributable deaths (SVADs) and life years lost (LYLs) in the status quo and the menthol ban scenarios from 2021 to 2060. RESULTS: Under the menthol ban scenario, overall smoking is projected to decline by 35.7% in 2026 and by 25.3% in 2060 relative to the status quo scenario. With these reductions, SVADs are estimated to fall by about 18.5% and LYLs by 22.1%, translating to 255 895 premature deaths averted, and 4.0 million life years gained over a 40-year period. CONCLUSIONS: A menthol cigarette ban will substantially reduce the smoking-associated health impact on the NHB population, thereby reducing health disparities.

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