Molecular Dynamics Analysis Reveals Structural Insights into Mechanism of Nicotine N-Demethylation Catalyzed by Tobacco Cytochrome P450 Mono-Oxygenase

CYP82E4, a cytochrome P450 monooxygenase, has nicotine N-demethylase (NND) activity, which mediates the bioconversion of nicotine into nornicotine in senescing tobacco leaves. Nornicotine is a precursor of the carcinogen, tobacco-specific nitrosamine. CYP82E3 is an ortholog of CYP82E4 with 95% sequence identity, but it lacks NND activity. A recent site-directed mutagenesis study revealed that a single amino acid substitution, i.e., cysteine to tryptophan at the 330 position in the middle of protein, restores the NND activity of CYP82E3 entirely. However, the same amino acid change caused the loss of the NND activity of CYP82E4. To determine the mechanism of the functional turnover of the two molecules, four 3D structures, i.e., the two molecules and their corresponding cys–trp mutants were modeled. The resulting structures exhibited that the mutation site is far from the active site, which suggests that no direct interaction occurs between the two sites. Simulation studies in different biological scenarios revealed that the mutation introduces a conformation drift with the largest change at the F-G loop. The dynamics trajectories analysis using principal component analysis and covariance analysis suggests that the single amino acid change causes the opening and closing of the transfer channels of the substrates, products, and water by altering the motion of the F-G and B-C loops. The motion of helix I is also correlated with the motion of both the F-G loop and the B-C loop and; the single amino acid mutation resulted in the curvature of helix I. These results suggest that the single amino acid mutation outside the active site region may have indirectly mediated the flexibility of the F-G and B-C loops through helix I, causing a functional turnover of the P450 monooxygenase

Diminishing benefits of urban living for children and adolescents’ growth and development

AbstractOptimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was &lt;1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.</jats:p

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI 2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining https://researchonline.ljmu.ac.uk/images/research_banner_face_lab_290.jpgunderweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity

Carboplatin plus paclitaxel once a week versus every 3 weeks in patients with advanced ovarian cancer (MITO-7): a randomised, multicentre, open-label, phase 3 trial.

ACKGROUND: Carboplatin plus paclitaxel administered every 3 weeks is standard first-line chemotherapy for patients with advanced ovarian cancer. A weekly paclitaxel schedule combined with carboplatin every 3 weeks prolonged progression-free survival and overall survival in a Japanese phase 3 trial. The aim of our study was to assess whether a weekly schedule of carboplatin plus paclitaxel is more effective than the same drugs given every 3 weeks. METHODS: We did a multicentre, randomised, phase 3 study at 67 institutions in Italy and France. Women with FIGO stage IC-IV ovarian cancer, an ECOG performance status of 2 or lower, and who had never received chemotherapy were randomly allocated in a 1:1 ratio to receive either carboplatin (AUC 6 mg/mL per min) plus paclitaxel (175 mg/m(2)) every 3 weeks for six cycles or carboplatin (AUC 2 mg/mL per min) plus paclitaxel (60 mg/m(2)) every week for 18 weeks. Randomisation was done by computer-based minimisation, stratified by centre, residual disease after surgery, and ECOG performance status. The study was not blinded. Coprimary endpoints were progression-free survival and quality of life (assessed by the Functional Assessment of Cancer Therapy Ovarian Trial Outcome Index [FACT-O/TOI] score), and analysis was by modified intention to treat. This report presents the final analysis. The study is registered with ClinicalTrials.gov, number NCT00660842. FINDINGS: 822 patients were enrolled into the study between Nov 20, 2008, and March 1, 2012; 12 withdrew their consent immediately after randomisation and were excluded, and 810 were eligible for analysis. 404 women were allocated treatment every 3 weeks and 406 were assigned to the weekly schedule. After median follow-up of 22·3 months (IQR 16·2-30·9), 449 progression-free survival events were recorded. Median progression-free survival was 17·3 months (95% CI 15·2-20·2) in patients assigned to treatment every 3 weeks, versus 18·3 months (16·8-20·9) in women allocated to the weekly schedule (hazard ratio 0·96, 95% CI 0·80-1·16; p=0·66). FACT-O/TOI scores differed significantly between the two schedules (treatment-by-time interaction p&lt;0·0001); with treatment every 3 weeks, FACT-O/TOI scores worsened at every cycle (weeks 1, 4, and 7), whereas for the weekly schedule, after transient worsening at week 1, FACT-O/TOI scores remained stable. Fewer patients assigned to the weekly group than those allocated treatment every 3 weeks had grade 3-4 neutropenia (167 [42%] of 399 patients vs 200 [50%] of 400 patients), febrile neutropenia (two [0·5%] vs 11 [3%]), grade 3-4 thrombocytopenia (four [1%] vs 27 [7%]), and grade 2 or worse neuropathy (24 [6%] vs 68 [17%]). Three deaths during the study were attributed to chemotherapy; two women died who were allocated treatment every 3 weeks and one death was recorded in the group assigned the weekly regimen. INTERPRETATION: A weekly regimen of carboplatin and paclitaxel might be a reasonable option for first-line treatment of women with advanced ovarian cancer

Randomised multicentre phase III study comparing weekly versus every-3-week carboplatin plus paclitaxel in patients with advanced ovarian cancer: the MITO-7 (Multicentre Italian Trials in Ovarian cancer) -ENGOT-OV-10 (European Network of Gynaecological Oncological Trial Groups) -GCIG (Gynecologic Cancer InterGroup) trial.

BACKGROUND: Carboplatin plus paclitaxel administered every 3 weeks is standard first-line chemotherapy for patients with advanced ovarian cancer. A weekly paclitaxel schedule combined with carboplatin every 3 weeks prolonged progression-free survival and overall survival in a Japanese phase 3 trial. The aim of our study was to assess whether a weekly schedule of carboplatin plus paclitaxel is more effective than the same drugs given every 3 weeks. METHODS: We did a multicentre, randomised, phase 3 study at 67 institutions in Italy and France. Women with FIGO stage IC-IV ovarian cancer, an ECOG performance status of 2 or lower, and who had never received chemotherapy were randomly allocated in a 1:1 ratio to receive either carboplatin (AUC 6 mg/mL per min) plus paclitaxel (175 mg/m(2)) every 3 weeks for six cycles or carboplatin (AUC 2 mg/mL per min) plus paclitaxel (60 mg/m(2)) every week for 18 weeks. Randomisation was done by computer-based minimisation, stratified by centre, residual disease after surgery, and ECOG performance status. The study was not blinded. Coprimary endpoints were progression-free survival and quality of life (assessed by the Functional Assessment of Cancer Therapy Ovarian Trial Outcome Index [FACT-O/TOI] score), and analysis was by modified intention to treat. This report presents the final analysis. The study is registered with ClinicalTrials.gov, number NCT00660842. FINDINGS: 822 patients were enrolled into the study between Nov 20, 2008, and March 1, 2012; 12 withdrew their consent immediately after randomisation and were excluded, and 810 were eligible for analysis. 404 women were allocated treatment every 3 weeks and 406 were assigned to the weekly schedule. After median follow-up of 22·3 months (IQR 16·2-30·9), 449 progression-free survival events were recorded. Median progression-free survival was 17·3 months (95% CI 15·2-20·2) in patients assigned to treatment every 3 weeks, versus 18·3 months (16·8-20·9) in women allocated to the weekly schedule (hazard ratio 0·96, 95% CI 0·80-1·16; p=0·66). FACT-O/TOI scores differed significantly between the two schedules (treatment-by-time interaction p&lt;0·0001); with treatment every 3 weeks, FACT-O/TOI scores worsened at every cycle (weeks 1, 4, and 7), whereas for the weekly schedule, after transient worsening at week 1, FACT-O/TOI scores remained stable. Fewer patients assigned to the weekly group than those allocated treatment every 3 weeks had grade 3-4 neutropenia (167 [42%] of 399 patients vs 200 [50%] of 400 patients), febrile neutropenia (two [0·5%] vs 11 [3%]), grade 3-4 thrombocytopenia (four [1%] vs 27 [7%]), and grade 2 or worse neuropathy (24 [6%] vs 68 [17%]). Three deaths during the study were attributed to chemotherapy; two women died who were allocated treatment every 3 weeks and one death was recorded in the group assigned the weekly regimen. INTERPRETATION: A weekly regimen of carboplatin and paclitaxel might be a reasonable option for first-line treatment of women with advanced ovarian cancer

Carboplatin plus paclitaxel once a week versus every 3 weeks in patients with advanced ovarian cancer (MITO-7): a randomised, multicentre, open-label, phase 3 trial.

Background: Carboplatin plus paclitaxel administered every 3 weeks is standard first-line chemotherapy for patients with advanced ovarian cancer. A weekly paclitaxel schedule combined with carboplatin every 3 weeks prolonged progression-free survival and overall survival in a Japanese phase 3 trial. The aim of our study was to assess whether a weekly schedule of carboplatin plus paclitaxel is more effective than the same drugs given every 3 weeks. Methods: We did a multicentre, randomised, phase 3 study at 67 institutions in Italy and France. Women with FIGO stage IC-IV ovarian cancer, an ECOG performance status of 2 or lower, and who had never received chemotherapy were randomly allocated in a 1:1 ratio to receive either carboplatin (AUC 6 mg/mL per min) plus paclitaxel (175 mg/m2) every 3 weeks for six cycles or carboplatin (AUC 2 mg/mL per min) plus paclitaxel (60 mg/m2) every week for 18 weeks. Randomisation was done by computer-based minimisation, stratified by centre, residual disease after surgery, and ECOG performance status. The study was not blinded. Coprimary endpoints were progression-free survival and quality of life (assessed by the Functional Assessment of Cancer Therapy Ovarian Trial Outcome Index [FACT-O/TOI] score), and analysis was by modified intention to treat. This report presents the final analysis. The study is registered with ClinicalTrials.gov, number NCT00660842. Findings: 822 patients were enrolled into the study between Nov 20, 2008, and March 1, 2012; 12 withdrew their consent immediately after randomisation and were excluded, and 810 were eligible for analysis. 404 women were allocated treatment every 3 weeks and 406 were assigned to the weekly schedule. After median follow-up of 22·3 months (IQR 16·2-30·9), 449 progression-free survival events were recorded. Median progression-free survival was 17·3 months (95% CI 15·2-20·2) in patients assigned to treatment every 3 weeks, versus 18·3 months (16·8-20·9) in women allocated to the weekly schedule (hazard ratio 0·96, 95% CI 0·80-1·16; p=0·66). FACT-O/TOI scores differed significantly between the two schedules (treatment-by-time interaction p<0·0001); with treatment every 3 weeks, FACT-O/TOI scores worsened at every cycle (weeks 1, 4, and 7), whereas for the weekly schedule, after transient worsening at week 1, FACT-O/TOI scores remained stable. Fewer patients assigned to the weekly group than those allocated treatment every 3 weeks had grade 3-4 neutropenia (167 [42%] of 399 patients vs 200 [50%] of 400 patients), febrile neutropenia (two [0·5%] vs 11 [3%]), grade 3-4 thrombocytopenia (four [1%] vs 27 [7%]), and grade 2 or worse neuropathy (24 [6%] vs 68 [17%]). Three deaths during the study were attributed to chemotherapy; two women died who were allocated treatment every 3 weeks and one death was recorded in the group assigned the weekly regimen. Interpretation: A weekly regimen of carboplatin and paclitaxel might be a reasonable option for first-line treatment of women with advanced ovarian cancer. Funding: None. © 2014 Elsevier Ltd