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1.
Gastroenterology ; 167(3): 485-492.e3, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38513743

RESUMEN

BACKGROUND & AIMS: Helicobacter pylori infection is associated with a decreased risk of esophageal adenocarcinoma, and the decreasing prevalence of such infection might contribute to the increasing incidence of this tumor. We examined the hypothesis that eradication treatment of H pylori increases the risk of esophageal adenocarcinoma. METHODS: This population-based multinational cohort, entitled "Nordic Helicobacter Pylori Eradication Project (NordHePEP)," included all adults (≥18 years) receiving H pylori eradication treatment from 1995-2018 in any of the 5 Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden) with follow-up throughout 2019. Data came from national registers. We calculated standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) by dividing the cancer incidence in the exposed cohort by that of the entire Nordic background populations of the corresponding age, sex, calendar period, and country. Analyses were stratified by factors associated with esophageal adenocarcinoma (ie, education, comorbidity, gastroesophageal reflux, and certain medications). RESULTS: Among 661,987 participants who contributed 5,495,552 person-years after eradication treatment (median follow-up, 7.8 years; range, 1-24 years), 550 cases of esophageal adenocarcinoma developed. The overall SIR of esophageal adenocarcinoma was not increased (SIR = 0.89; 95% CI, 0.82-0.97). The SIR did not increase over time after eradication treatment, but rather decreased and was 0.73 (95% CI, 0.61-0.86) at 11-24 years after treatment. There were no major differences in the stratified analyses. The overall SIR of esophageal squamous cell carcinoma, calculated for comparison, showed no association (SIR = 0.99; 95% CI, 0.89-1.11). CONCLUSIONS: This absence on an increased risk of esophageal adenocarcinoma after eradication treatment of H pylori suggests eradication is safe from a cancer perspective.


Asunto(s)
Adenocarcinoma , Antibacterianos , Neoplasias Esofágicas , Infecciones por Helicobacter , Helicobacter pylori , Humanos , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/microbiología , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/diagnóstico , Adenocarcinoma/epidemiología , Adenocarcinoma/microbiología , Masculino , Femenino , Persona de Mediana Edad , Helicobacter pylori/efectos de los fármacos , Antibacterianos/uso terapéutico , Incidencia , Anciano , Adulto , Factores de Riesgo , Países Escandinavos y Nórdicos/epidemiología , Inhibidores de la Bomba de Protones/uso terapéutico , Inhibidores de la Bomba de Protones/efectos adversos , Medición de Riesgo , Sistema de Registros
2.
Small ; : e2400096, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38516956

RESUMEN

The extremely poor solution stability and massive carrier recombination have seriously prevented III-V semiconductor nanomaterials from efficient and stable hydrogen production. In this work, an anodic reconstruction strategy based on group III-V active semiconductors is proposed for the first time, resulting in 19-times photo-gain. What matters most is that the device after anodic reconstruction shows very superior stability under the protracted photoelectrochemical (PEC) test over 8100 s, while the final photocurrent density does not decrease but rather increases by 63.15%. Using the experiment and DFT theoretical calculation, the anodic reconstruction mechanism is elucidated: through the oxidation of indium clusters and the migration of arsenic atoms, the reconstruction formed p+-GaAs/a-InAsN. The hole concentration of the former is increased by 10 times (5.64 × 1018 cm-1 increases up to 5.95 × 1019 cm-1) and the band gap of the latter one is reduced to a semi-metallic state, greatly strengthening the driving force of PEC water splitting. This work turns waste into treasure, transferring the solution instability into better efficiency.

3.
Environ Sci Technol ; 58(1): 883-894, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38134887

RESUMEN

Transition metal catalysts, such as copper oxide, are more attractive alternatives to noble metal catalysts for emission control due to their higher abundance, lower cost, and excellent catalytic activity. In this study, we report the preparation and application of a novel CuO/CeO2 catalyst using a hydroxyl-rich Ce(OH)x support for CO oxidation and NO reduction by CO. Compared to the catalyst prepared from a regular CeO2 support, the new CuO/CeO2 catalyst prepared from the OH-rich Ce(OH)x (CuO/CeO2-OH) showed significantly higher catalytic activity under different testing conditions. The effect of OH species in the CeO2 support on the catalytic performance and physicochemical properties of the CuO/CeO2 catalyst was characterized in detail. It is demonstrated that the abundant OH species enhanced the CuOx dispersion on CeO2, increased the CuOx-CeO2 interfaces and surface defects, promoted the oxygen activation and mobility, and boosted the NO adsorption and dissociation on CuO/CeO2-OH, thus contributing to its superior catalytic activity for both CO oxidation and NO reduction by CO. These results suggest that the OH-rich Ce(OH)x is a superior support for the preparation of highly efficient metal catalysts for different applications.


Asunto(s)
Elementos de Transición , Oxidación-Reducción , Oxígeno , Radical Hidroxilo , Catálisis
4.
Environ Sci Technol ; 58(28): 12731-12741, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38958431

RESUMEN

Effective synthesis and application of single-atom catalysts on supports lacking enough defects remain a significant challenge in environmental catalysis. Herein, we present a universal defect-enrichment strategy to increase the surface defects of CeO2-based supports through H2 reduction pretreatment. The Pt catalysts supported by defective CeO2-based supports, including CeO2, CeZrOx, and CeO2/Al2O3 (CA), exhibit much higher Pt dispersion and CO oxidation activity upon reduction activation compared to their counterpart catalysts without defect enrichment. Specifically, Pt is present as embedded single atoms on the CA support with enriched surface defects (CA-HD) based on which the highly active catalyst showing embedded Pt clusters (PtC) with the bottom layer of Pt atoms substituting the Ce cations in the CeO2 surface lattice can be obtained through reduction activation. Embedded PtC can better facilitate CO adsorption and promote O2 activation at PtC-CeO2 interfaces, thereby contributing to the superior low-temperature CO oxidation activity of the Pt/CA-HD catalyst after activation.


Asunto(s)
Monóxido de Carbono , Oxidación-Reducción , Platino (Metal) , Monóxido de Carbono/química , Platino (Metal)/química , Catálisis , Cerio/química , Adsorción , Propiedades de Superficie
5.
Chemistry ; 29(16): e202203432, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36567623

RESUMEN

The size effect on nanoparticles, which affects the catalysis performance in a significant way, is crucial. The tuning of oxygen vacancies on metal-oxide support can help reduce the size of the particles in active clusters of Pt, thus improving catalysis performance of the supported catalyst. Herein, Ce-Sn solid solutions (CSO) with abundant oxygen vacancies have been synthesized. Activated by simple CO reduction after loading Pt species, the catalytic CO oxidation performance of Pt/CSO was significantly better than that of Pt/CeO2 . The reasons for the elevated activity were further explored regarding ionic Pt single sites being transformed into active Pt clusters after CO reduction. Due to more exposed oxygen vacancies, much smaller Pt clusters were created on CSO (ca. 1.2 nm) than on CeO2 (ca. 1.8 nm). Consequently, more exposed active Pt clusters significantly improved the ability to activate oxygen and directly translated to the higher catalytic oxidation performance of activated Pt/CSO catalysts in vehicle emission control applications.

6.
Scand J Gastroenterol ; 58(5): 453-459, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36369751

RESUMEN

PURPOSE: This cohort description presents the Nordic Helicobacter Pylori Eradication Project (NordHePEP), a population-based cohort of patients having received eradication treatment for Helicobacter pylori (HP). The cohort is created with the main purpose of examining whether and to what extent HP eradication treatment influences the risk of gastrointestinal cancer. PARTICIPANTS: NordHePEP includes all adults (aged ≥18 years) having been prescribed and dispensed HP eradication treatment according to the nationwide complete drug registries in any of the five Nordic countries (Denmark, Finland, Iceland, Norway, or Sweden) between 1994 and 2020 (start and end year varies between countries). We have retrieved and merged individual-level data from multiple national registries, including drug, patient, cancer, population, and death registries. FINDINGS: The cohort includes 674,771 patients having received HP eradication treatment. During up to 23 years of follow-up, 59,292 (8.8%) participants were diagnosed with cancer (non-melanoma skin cancer excluded), whereof 15,496 (2.3%) in the gastrointestinal tract. FUTURE PLANS: We will analyse HP eradication treatment in relation to gastrointestinal cancer risk. Standardised incidence ratios will be calculated as the observed cancer incidence in the cohort divided by the expected cancer incidence, derived from the background population of the corresponding age, sex, and calendar year.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Neoplasias , Adulto , Humanos , Adolescente , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/epidemiología , Neoplasias/epidemiología , Países Escandinavos y Nórdicos/epidemiología , Islandia/epidemiología , Antibacterianos/uso terapéutico
7.
Acta Oncol ; 62(5): 438-443, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37216488

RESUMEN

BACKGROUND: We hypothesised that the use of the anti-androgenic drug 5α-reductase inhibitors (5-ARIs) improves survival in patients with oesophago-gastric cancer. METHODS: This nationwide Swedish population-based cohort study included men who underwent surgery for oesophageal or gastric cancer between 2006-2015, with follow-up until the end of 2020. Multivariable Cox regression estimated hazard ratios (HR) for associations between 5-ARIs use and 5-year all-cause mortality (main outcome) and 5-year disease-specific mortality (secondary outcome). The HR was adjusted for age, comorbidity, education, calendar year, neoadjuvant chemo(radio)therapy, tumour stage, and resection margin status. RESULTS: Among 1769 patients with oesophago-gastric cancer, 64 (3.6%) were users of 5-ARIs. Compared to non-users, users of 5-ARIs were not at any decreased risk of 5-year all-cause mortality (adjusted HR 1.13, 95% CI 0.79-1.63) or 5-year disease-specific mortality (adjusted HR 1.10, 95% CI 0.79-1.52). Use of 5-ARIs was not associated with any decreased risk of 5-year all-cause mortality in subgroup analyses stratified by categories of age, comorbidity, tumour stage, or tumour subtype (oesophageal or cardia adenocarcinoma, non-cardia gastric adenocarcinoma, or oesophageal squamous cell carcinoma). CONCLUSION: This study did not support the hypothesis of improved survival among users of 5-ARIs after curatively intended treatment for oesophago-gastric cancer.


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Masculino , Humanos , Estudios de Cohortes , Inhibidores de 5-alfa-Reductasa/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Suecia/epidemiología , Neoplasias Esofágicas/tratamiento farmacológico , Adenocarcinoma/patología , Oxidorreductasas
8.
Environ Sci Technol ; 57(9): 3962-3970, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36808945

RESUMEN

Chlorate (ClO3-) is a common water pollutant due to its gigantic scale of production, wide applications in agriculture and industry, and formation as a toxic byproduct in various water treatment processes. This work reports on the facile preparation, mechanistic elucidation, and kinetic evaluation of a bimetallic catalyst for highly active ClO3- reduction into Cl-. Under 1 atm H2 and 20 °C, PdII and RuIII were sequentially adsorbed and reduced on a powdered activated carbon support, affording Ru0-Pd0/C from scratch within only 20 min. The Pd0 particles significantly accelerated the reductive immobilization of RuIII as >55% dispersed Ru0 outside Pd0. At pH 7, Ru-Pd/C shows a substantially higher activity of ClO3- reduction (initial turnover frequency >13.9 min-1 on Ru0; rate constant at 4050 L h-1 gmetal-1) than reported catalysts (e.g., Rh/C, Ir/C, Mo-Pd/C) and the monometallic Ru/C. In particular, Ru-Pd/C accomplished the reduction of concentrated 100 mM ClO3- (turnover number > 11,970), whereas Ru/C was quickly deactivated. In the bimetallic synergy, Ru0 rapidly reduces ClO3- while Pd0 scavenges the Ru-passivating ClO2- and restores Ru0. This work demonstrates a simple and effective design for heterogeneous catalysts tailored for emerging water treatment needs.


Asunto(s)
Cloratos , Paladio , Oxidación-Reducción , Concentración de Iones de Hidrógeno
9.
Environ Sci Technol ; 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36633933

RESUMEN

Adding CrIII or AlIII salts into the water suspension of platinum group metal (PGM) catalysts accelerated oxyanion pollutant reduction by up to 600%. Our initial attempts of adding K2CrVIO4, K2CrVI2O7, or KCrIII(SO4)2 into Pd/C enhanced BrO3- reduction with 1 atm H2 by 6-fold. Instrument characterizations and kinetic explorations collectively confirmed the immobilization of reduced CrVI as CrIII(OH)3 on the catalyst surface. This process altered the ζ-potentials from negative to positive, thus substantially enhancing the Langmuir-Hinshelwood adsorption equilibrium constant for BrO3- onto Pd/C by 37-fold. Adding AlIII(OH)3 from alum at pH 7 achieved similar enhancements. The Cr-Pd/C and Al-Pd/C showed top-tier efficiency of catalytic performance (normalized with Pd dosage) among all the reported Pd catalysts on conventional and nanostructured support materials. The strategy of adding inert metal hydroxides works for diverse PGMs (palladium and rhodium), substrates (BrO3- and ClO3-), and support materials (carbon, alumina, and silica). This work shows a simple, inexpensive, and effective example of enhancing catalyst activity and saving PGMs for environmental applications.

10.
Environ Sci Technol ; 57(41): 15747-15758, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37788364

RESUMEN

Aiming at the development of an efficient NH3 oxidation catalyst to eliminate the harmful NH3 slip from the stationary flue gas denitrification system and diesel exhaust aftertreatment system, a facile ZrO2 doping strategy was proposed to construct Pt1/CexZr1-xO2 catalysts with a tunable Pt-CeO2 interaction strength and Pt-O-Ce coordination environment. According to the results of systematic characterizations, Pt species supported on CexZr1-xO2 were mainly in the form of single atoms when x ≥ 0.7, and the strength of the Pt-CeO2 interaction and the coordination number of Pt-O-Ce bond (CNPt-O-Ce) on Pt1/CexZr1-xO2 showed a volcanic change as a function of the ZrO2 doping amount. It was proposed that the balance between the reasonable concentration of oxygen defects and limited surface Zr-Ox species well accounted for the strongest Pt-CeO2 interaction and the highest CNPt-O-Ce on Pt/Ce0.9Zr0.1O2. It was observed that the Pt/Ce0.9Zr0.1O2 catalyst exhibited much higher NH3 oxidation activity than other Pt/CexZr1-xO2 catalysts. The mechanism study revealed that the Pt1 species with the stronger Pt-CeO2 interaction and higher CNPt-O-Ce within Pt/Ce0.9Zr0.1O2 could better activate NH3 adsorbed on Lewis acid sites to react with O2 thus resulting in superior NH3 oxidation activity. This work provides a new approach for designing highly efficient Pt/CeO2 based catalysts for low-temperature NH3 oxidation.


Asunto(s)
Amoníaco , Platino (Metal) , Amoníaco/química , Oxidación-Reducción , Circonio/química , Oxígeno , Catálisis
11.
Environ Sci Technol ; 57(43): 16685-16694, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37864569

RESUMEN

Selective catalytic reduction of NOx by NH3 (NH3-SCR) for diesel emission control at low temperatures is still a great challenge due to the limit of the urea injection threshold and inferior SCR activity of state-of-the-art catalyst systems below 200 °C. Fabricating bifunctional catalysts with both low temperature NOx adsorption-storage capacity and medium-high temperature NOx reduction activity is an effective strategy to solve the issues mentioned above but is rarely investigated. Herein, the WO3/Ce0.68Zr0.32Ox (W/CZ) catalyst containing the κ-Ce2Zr2O8 pyrochlore structure was successfully developed by a simple H2 reduction method, not only showing superior NOx adsorption-storage ability below 180 °C but also exhibiting excellent NH3-SCR activity above 180 °C. The presence of the pyrochlore structure effectively increased the oxygen vacancies on the κ-Ce2Zr2O8-containing W/CZ catalyst with enhanced redox property, which significantly promoted the NOx adsorption-storage as active nitrate species below 180 °C. Upon NH3 introduction above 180 °C, the κ-Ce2Zr2O8-containing W/CZ catalyst showed greatly improved NOx reduction performance, suggesting that the pyrochlore structure played a vital role in improving the NOx adsorption-selective catalytic reduction (AdSCR) performance. This work provides a new perspective for designing bifunctional CeZrOx-based catalysts to efficiently control the NOx emissions from diesel engines during the cold-start process.


Asunto(s)
Amoníaco , Niobio , Adsorción , Amoníaco/química , Oxidación-Reducción , Catálisis
12.
Environ Sci Technol ; 57(33): 12501-12512, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37563957

RESUMEN

Tuning the metal-support interaction and coordination environment of single-atom catalysts can help achieve satisfactory catalytic performance for targeted reactions. Herein, via the facile control of calcination temperatures for Pt catalysts on pre-stabilized Ce0.9Zr0.1O2 (CZO) support, Pt single atoms (Pt1) with different strengths of Pt-CeO2 interaction and coordination environment were successfully constructed. With the increase in calcination temperature from 350 to 750 °C, a stronger Pt-CeO2 interaction and higher Pt-O-Ce coordination number were achieved due to the reaction between PtOx and surface Ce3+ species as well as the migration of Pt1 into the surface lattice of CZO. The Pt/CZO catalyst calcined at 750 °C (Pt/CZO-750) exhibited a surprisingly higher C3H8 oxidation activity than that calcined at 550 °C (Pt/CZO-550). Through systematic characterizations and reaction mechanism study, it was revealed that the higher concentration of surface Ce3+ species/oxygen vacancies and the stronger Pt-CeO2 interaction on Pt/CZO-750 could better facilitate the activation of oxygen to oxidize C3H8 into reactive carbonate/carboxyl species and further promote the transformation of these intermediates into gaseous CO2. The Pt/CZO-750 catalyst can be a potential candidate for the catalytic removal of hydrocarbons from vehicle exhaust.


Asunto(s)
Oxígeno , Propano , Catálisis , Oxidación-Reducción
13.
J Am Chem Soc ; 144(46): 21255-21266, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36322840

RESUMEN

The local coordination structure of metal sites essentially determines the performance of supported metal catalysts. Using a surface defect enrichment strategy, we successfully fabricated Pt atomic single-layer (PtASL) structures with 100% metal dispersion and precisely controlled local coordination environment (embedded vs adsorbed) derived from Pt single-atoms (Pt1) on ceria-alumina supports. The local coordination environment of Pt1 not only governs its catalytic activity but also determines the Pt1 structure evolution upon reduction activation. For CO oxidation, the highest turnover frequency can be achieved on the embedded PtASL in the CeO2 lattice, which is 3.5 times of that on the adsorbed PtASL on the CeO2 surface and 10-70 times of that on Pt1. The favorable CO adsorption on embedded PtASL and improved activation/reactivity of lattice oxygen within CeO2 effectively facilitate the CO oxidation. This work provides new insights for the precise control of the local coordination structure of active metal sites for achieving 100% atomic utilization efficiency and optimal intrinsic catalytic activity for targeted reactions simultaneously.

14.
Br J Cancer ; 126(1): 129-133, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34671128

RESUMEN

BACKGROUND: Oesophageal adenocarcinoma is characterised by a strong male predominance. We aimed to test the hypothesis that menopausal hormonal therapy decreases the risk of oesophageal adenocarcinoma. METHODS: This population-based cohort study included all women who used systemic menopausal hormonal therapy (exposed) in Sweden between 2005 and 2018. For each exposed participant, five randomly selected female age-matched non-users of menopausal hormonal therapy (unexposed) were included. Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, smoking-related diagnoses, Helicobacter pylori eradication, use of non-steroidal anti-inflammatory drugs/aspirin, use of statins and hysterectomy. RESULTS: The study included 296,964 users of menopausal hormonal therapy and 1,484,820 non-users. Ever-users of menopausal hormonal therapy had an overall decreased risk of oesophageal adenocarcinoma (HR 0.78, 95% CI 0.63-0.97), which remained unchanged after further adjustment for gastro-oesophageal reflux disease (HR 0.78, 95% CI 0.63-0.97) and obesity/diabetes (HR 0.79, 95% CI 0.63-0.98). Decreased HRs were indicated both in users of oestrogen only (HR 0.82, 95% CI 0.60-1.12) and oestrogen combined with progestogen (HR 0.75, 95% CI 0.56-1.00). The risk reduction was more pronounced in users younger than 60 years (HR 0.57, 95% CI 0.38-0.86). CONCLUSIONS: Menopausal hormone therapy in women may decrease the risk of oesophageal adenocarcinoma.


Asunto(s)
Adenocarcinoma/patología , Aspirina/uso terapéutico , Neoplasias Esofágicas/patología , Terapia de Reemplazo de Hormonas/efectos adversos , Menopausia , Adenocarcinoma/inducido químicamente , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/epidemiología , Antiinflamatorios no Esteroideos/uso terapéutico , Estudios de Cohortes , Neoplasias Esofágicas/inducido químicamente , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Factores de Riesgo , Suecia/epidemiología
15.
Br J Cancer ; 127(5): 892-897, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35715630

RESUMEN

BACKGROUND: To investigate if anti-androgenic medications 5α-reductase inhibitors (5-ARIs) decrease the risk of developing oesophageal and gastric tumours, analysed by histological type and anatomical sub-site. METHODS: A Swedish population-based cohort study between 2005 and 2018 where men using 5-ARIs were considered exposed. For each exposed participant, ten male age-matched non-users of 5-ARIs (non-exposed) were included. Multivariable Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, calendar year, smoking, non-steroidal anti-inflammatory drugs/aspirin use, and statins use. Further adjustments were made depending on the tumour analysed. RESULTS: The cohort included 191,156 users of 5-ARIs and 1,911,560 non-users. Overall, the use of 5-ARIs was not associated with any statistically significantly reduced risk of oesophageal or cardia adenocarcinoma (adjusted HR 0.92, 95% CI 0.82-1.02) or gastric non-cardia adenocarcinoma (adjusted HR 0.90, 95% CI 0.80-1.02). However, the use of 5-ARIs indicated a decreased risk of oesophageal or cardia adenocarcinoma among obese or diabetic participants (adjusted HR 0.55, 95% CI 0.39-0.80) and a reduced risk of oesophageal squamous cell carcinoma (adjusted HR 0.49, 95% CI 0.37-0.65). CONCLUSION: Users of 5-ARIs may have a decreased risk of developing oesophageal or cardia adenocarcinoma among those obese or diabetic, and a decreased risk of oesophageal squamous cell carcinoma.


Asunto(s)
Adenocarcinoma , Diabetes Mellitus , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias Gástricas , Inhibidores de 5-alfa-Reductasa/uso terapéutico , Antagonistas de Andrógenos/efectos adversos , Estudios de Cohortes , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/etiología , Humanos , Masculino , Obesidad , Oxidorreductasas , Factores de Riesgo , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/etiología
16.
Br J Cancer ; 126(7): 1100-1107, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35027671

RESUMEN

BACKGROUND: This systematic review and meta-analysis examined associations between serum levels of haemoglobin A1c (HbA1c) and glucose and the risk of gastric cancer. METHODS: MEDLINE, Embase, and Cochrane Library were searched for studies examining associations between serum levels of HbA1c or glucose and the risk of gastric cancer. Inclusion of studies, quality assessment, and data extraction were conducted independently by two authors. Pooled hazard ratios (HR) with 95% confidence intervals (CI) were synthesised using random-effects models. Cochran's Q test and I2 statistic were used to assess heterogeneity. RESULTS: Among 3473 identified studies, 12 were included. Of these, 5 studies examined HbA1c levels and 7 studies examined serum glucose levels. Serum HbA1c levels >6% were associated with an increased risk of gastric cancer (HR 1.36, 95% CI 1.06-1.74). When compared with the lowest glucose categories, the highest glucose categories were associated with a borderline increased risk of gastric cancer (HR 1.11, 95% CI 0.98-1.26). In subgroup analyses, studies that adjusted for Helicobacter pylori infection indicated stronger associations between elevated HbA1c levels and gastric cancer (HR 2.08, 95% CI 1.46-2.98) than those without such adjustment (HR 1.10, 95% CI 0.91-1.32). CONCLUSIONS: Long-standing poor glycaemic control may increase the risk of gastric cancer. REGISTRATION NUMBER: PROSPERO CRD42020157453.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Glucosa , Hemoglobina Glucada , Infecciones por Helicobacter/complicaciones , Humanos , Neoplasias Gástricas/epidemiología
17.
Gastric Cancer ; 25(3): 652-658, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35166957

RESUMEN

BACKGROUND: Low-dose aspirin use may reduce cancer incidence and mortality, but its influence on gastric adenocarcinoma survival is unclear. This study aimed to assess whether aspirin use improves long-term survival following gastrectomy for gastric adenocarcinoma. METHODS: This population-based cohort study included almost all patients who underwent gastrectomy for gastric adenocarcinoma in Sweden from 2006 to 2015, with follow-up throughout 2020. Preoperative exposure to a daily low-dose (75-160 mg) aspirin for 1 (main exposure), 2 and 3 years and for 1 year after gastrectomy was examined in relation to 5-year all-cause mortality (primary outcome) and disease-specific mortality. Multivariable Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI), adjusted for age, sex, education, calendar year, comorbidity, statin use, tumour location, tumour stage, neoadjuvant chemotherapy, surgeon volume of gastrectomy and surgical radicality. RESULTS: Among 2025 patients, 545 (26.9%) used aspirin at the date of gastrectomy. Aspirin use within 1 year before surgery did not decrease the adjusted risk of 5-year all-cause mortality (HR = 0.98, 95% CI 0.85-1.13) or disease-specific mortality (HR = 1.00, 95% CI 0.86-1.17). Preoperative aspirin use for 2 years (HR = 0.98, 95% CI 0.84-1.15) or 3 years (HR = 0.94, 95% CI 0.79-1.12) did not decrease the risk of 5-year all-cause mortality. Patients remaining on aspirin during the first year after gastrectomy had a similar 5-year all-cause mortality as non-users of aspirin (HR = 1.01, 95% CI 0.82-1.25). CONCLUSIONS: Low-dose aspirin use might not improve long-term survival after gastrectomy for gastric adenocarcinoma and may thus not be a target for adjuvant therapy in this group of patients.


Asunto(s)
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Aspirina/uso terapéutico , Estudios de Cohortes , Gastrectomía , Humanos , Estadificación de Neoplasias , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía
18.
Environ Sci Technol ; 56(13): 9672-9682, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35728271

RESUMEN

Pt-based catalysts can be poisoned by the chlorine formed during the oxidation of multicomponent volatile organic compounds (VOCs) containing chlorinated VOCs. Improving the low-temperature chlorine resistance of catalysts is important for industrial applications, although it is yet challenging. We hereby demonstrate the essential catalytic roles of a bifunctional catalyst with an atomic-scale metal/oxide interface constructed by an intermetallic compound nanocrystal. Introducing trichloroethylene (TCE) exhibits a less negative effect on the catalytic activity of the bimetallic catalyst for o-xylene oxidation, and the partial deactivation caused by TCE addition is reversible, suggesting that the bimetallic, HCl-etched Pt3Sn(E)/CeO2 catalyst possesses much stronger chlorine resistance than the conventional Pt/CeO2 catalyst. On the site-isolated Pt-Sn catalyst, the presence of aromatic hydrocarbon significantly inhibits the adsorption strength of TCE, resulting in excellent catalytic stability in the oxidation of the VOC mixture. Furthermore, the large amount of surface-adsorbed oxygen species generated on the electronegative Pt is highly effective for low-temperature C-Cl bond dissociation. The adjacent promoter (Sn-O) possesses the functionality of acid sites to provide sufficient protons for HCl formation over the bifunctional catalyst, which is considered critical to maintaining the reactivity of Pt by removing Cl and decreasing the polychlorinated byproducts.

19.
Cardiovasc Drugs Ther ; 36(6): 1121-1128, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-34241731

RESUMEN

PURPOSE: Due to shared hepatic metabolism, concomitant medication with a proton pump inhibitor (PPI) and clopidogrel might reduce the effectiveness of clopidogrel in the prevention of cardiovascular events after percutaneous coronary intervention (PCI). We aimed to examine the risk of major cardiovascular events after PCI comparing patients who used clopidogrel together with PPI with those who used clopidogrel alone. METHODS: This Swedish nationwide cohort study included patients who received clopidogrel after primary PCI in 2005-2019. Patients were followed for up to 12 months after PCI. Data were retrieved from the Swedish Prescribed Drug Registry, Patient Registry, Cancer Registry, and Cause of Death Registry. Multivariable Cox regression provided hazard ratios (HRs) with 95% confidence intervals (CIs) for cardiovascular events comparing PPI users (exposed) with non-users of PPI (non-exposed). The HRs were adjusted for sex, age, comorbidity, calendar period, obesity, diabetes, anti-diabetic medication, tobacco-related diseases, hypertension, and congestive heart failure. RESULTS: The cohort included 99,836 patients who received clopidogrel after primary PCI. Among these, 35,772 (35.8%) received concomitant PPI. Compared to non-users, PPI users had increased adjusted HRs of all study outcomes, i.e., the main outcome myocardial infarction (HR = 1.23, 95% CI 1.15-1.32) and the secondary outcomes coronary heart disease (HR = 1.28, 95% CI 1.24-1.33), stroke (HR = 1.21, 95% CI 1.05-1.40), and death due to coronary heart disease (HR = 1.52, 95% CI 1.37-1.69). The results were similar in analyses including both primary and secondary PCIs. CONCLUSIONS: In patients who receive clopidogrel after PCI, concomitant use of PPI seems to increase the risk of major cardiovascular events.


Asunto(s)
Enfermedad Coronaria , Infarto del Miocardio , Intervención Coronaria Percutánea , Humanos , Clopidogrel/efectos adversos , Inhibidores de la Bomba de Protones/efectos adversos , Intervención Coronaria Percutánea/efectos adversos , Ticlopidina/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios de Cohortes , Infarto del Miocardio/tratamiento farmacológico , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/tratamiento farmacológico , Resultado del Tratamiento
20.
J Am Chem Soc ; 143(15): 5691-5697, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33843229

RESUMEN

Singlet fission (SF), the conversion of one high-energy singlet to two low-energy triplets, provides the potential to increase the efficiency of photovoltaic devices. In the SF chromophores with C2h symmetry, exemplified by polyenes, singlet-to-triplet conversion generally involves a low-lying 21Ag dark state, which serves as either a multiexciton (ME) intermediate to promote the SF process or a parasitic trap state to shunt excited-state populations via internal conversion. This controversial behavior calls for a deep understanding of dark-state-related photophysics involving the higher-lying singlet state. However, the optical "dark" and "transient" nature of these dark states and strong correlation feature of double exciton species make their characterization and interpretation challenging from both experimental and computational perspectives. In the present work combining transient spectroscopy and multireference electronic structure calculations (XDW-CASPT2), we addressed a new photophysical model, i.e., a high-lying 31Ag dark-state-mediated ultrafast SF process in the benzodipyrrolidone (BDPP) skeleton. Such a 31Ag dark state with distinctive double excitation character, described as the ME state, could be populated from the initial 11Bu bright state on an ultrafast time scale given the quasi-degeneracy and intersection of the two electronic states. Furthermore, the suitable optical band gap and triplet energy, high triplet yield, and excellent photostability render BDPP a promising SF candidate for photovoltaic devices. These results not only enrich the arsenal of SF materials but also shed new insights into the understanding of dark-state-related photophysics, which could promote the development of new SF-active materials.

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