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1.
Artículo en Inglés | MEDLINE | ID: mdl-38919514

RESUMEN

Gastric mucosal changes associated with long-term potassium-competitive acid blocker and proton pump inhibitor (PPI) therapy may raise concern. In contrast to that for PPIs, the evidence concerning the safety of long-term potassium-competitive acid blocker use is scant. Vonoprazan (VPZ) is a representative potassium-competitive acid blocker released in Japan in 2015. In order to shed some comparative light regarding the outcomes of gastric mucosal lesions associated with a long-term acid blockade, we have reviewed six representative gastric mucosal lesions: fundic gland polyps, gastric hyperplastic polyps, multiple white and flat elevated lesions, cobblestone-like gastric mucosal changes, gastric black spots, and stardust gastric mucosal changes. For these mucosal lesions, we have evaluated the association with the type of acid blockade, patient gender, Helicobacter pylori infection status, the degree of gastric atrophy, and serum gastrin levels. There is no concrete evidence to support a significant relationship between VPZ/PPI use and the development of neuroendocrine tumors. Current data also shows that the risk of gastric mucosal changes is similar for long-term VPZ and PPI use. Serum hypergastrinemia is not correlated with the development of some gastric mucosal lesions. Therefore, serum gastrin level is unhelpful for risk estimation and for decision-making relating to the cessation of these drugs in routine clinical practice. Given the confounding potential neoplastic risk relating to H. pylori infection, this should be eradicated before VPZ/PPI therapy is commenced. The evidence to date does not support the cessation of clinically appropriate VPZ/PPI therapy solely because of the presence of these associated gastric mucosal lesions.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124994, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39173317

RESUMEN

Sodium salicylate (NaSA) molecule exists as salicylate anion in acetonitrile (ACN) and water solvents, and exhibits large Stokes shifted fluorescence due to excited state intramolecular proton transfer (ESIPT), with decay times of âˆ¼5 ns in ACN and âˆ¼3.9 ns in water by 300 nm (absorption maxima) excitation. Previous studies report both ground and excited state enol-keto tautomerization in ACN, but only excited state tautomerization in water at 10-4 M. However, the current work explores the effect of concentration and excitation wavelengths on the photoinduced dynamics of ESIPT in the salicylate anion. On increasing the concentration of NaSA, no change in absorption spectra appears in both the solvents, and emission spectra of NaSA in water remain unaffected by changes in concentration or excitation wavelength, whereas, a slight red shift and decrease in FWHM appears in ACN. Time-domain fluorescence measurements show predominantly single-exponential decay throughout the emission profile by 300 nm excitation above the 10-5 M concentration in both the solvents, while by 375 nm excitation, multi-exponential fluorescence decay is observed at low concentrations, and as the concentration of NaSA increases, this decay behaviour tends to converge towards a single exponential decay. These results suggest that solute-solvent interactions stabilize the ground-state intermolecular hydrogen-bonded species at low concentrations, while higher concentrations weaken these interactions, leading to emission solely from the salicylate anion. Peak fit analysis of excitation spectra confirms enol-keto tautomerization in both the solvents, with the keto form being more stabilized in ACN. These findings underscore that in ACN, behaviour of NaSA is influenced by both concentration and excitation wavelength and contrary to previous reports, the keto form of the molecule is also present in water, though at a very low concentration and an increase in non-radiative transitions in water cause fluorescence quenching.

3.
World J Gastrointest Endosc ; 16(9): 526-532, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39351177

RESUMEN

BACKGROUND: Helicobacter pylori (H. pylori) is the most common chronic bacterial infection in humans. The risk of acquiring H. pylori is related to socioeconomic status and living conditions early in life. Treatment regimens must consider local antibiotic resistance patterns. Adventist Health White Memorial Hospital serves a predominantly indigent population in east Los Angeles with a large number of immigrants from South and Central America. Data regarding the prevalence and resistance of H. pylori in this population is scant. AIM: To evaluate the prevalence and resistance of H. pylori and correlate with country of origin. METHODS: All gastric biopsies were obtained by a single gastroenterologist at the hospital in a consecutive manner from patients with gastritis from 2017 to 2022 and sent to various labs for evaluation. RESULTS: Two hundred and sixty-six patients are born in the United States, 450, 171, 70, and 30 patients are immigrants from Mexico, Central and South America (CSA), Asia, and other countries respectively. Overall, 14.65% were found to be infected with H. pylori. Rates of infection in United States-born citizens, immigrants from Mexico, CSA, and Asia are 9.02%, 18.67%, 13.45%, and 11.43% respectively, with Mexican immigrants having a relative risk of 2.3889 [95% confidence interval (CI): 1.4789-3.8588, P = 0.0004] compared to those born in United States. No correlation seen between infection and length of time immigrants were in United States. Relative risk of infection in patients with no proton pump inhibitor use within the past 30 days found to be 1.9276 (95%CI: 1.3562-2.7398, P = 0.0003). Rates of resistance for clarithromycin and levofloxacin are 21.43% and 31.11%. CONCLUSION: H. pylori infection appears to be associated with low socioeconomic status and poor living conditions early in life. Clarithromycin and levofloxacin based treatment regimens should be avoided as first line therapy in this region, particularly in patients of Latin American origin.

4.
Adv Sci (Weinh) ; : e2407570, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39352320

RESUMEN

Anode cell reversal typically leads to severe carbon corrosion and catalyst layer collapse, which significantly compromises the durability of proton exchange membrane fuel cells. Herein, three types of commercial carbon supports with various structures are facilely coated by polyaniline (PANI) and subsequently fabricated into reversal-tolerant anodes (RTAs). Consequently, the optimized PANI-coated catalyst RTAs demonstrate enhanced polarization performance and improved reversal tolerance compared to their uncoated counterparts, thus confirming the universality of this coating strategy. Essentially, the surface engineering introduced by PANI coating incorporates abundant N-groups and enhances coulombic interactions with ionomer side chains, which in turn reduces lower carbon exposure, promotes more uniform Pt deposition, and ensures better ionomer distribution. Accordingly, the membrane-electrode-assembly containing the Pt/PANI/XC-72R-1+IrO2 RTA presents a 100 mV (at 2500 mA cm-2) polarization performance improvement and 26-fold reduction in the degradation rate compared to the uncoated counterpart. This work provides a universal strategy for developing durable anodes and lays the groundwork for the practical fabrication of high-performance, low-degradation RTA.

5.
Adv Mater ; : e2412541, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39350447

RESUMEN

Chemical synthesis of unconventional topologically close-packed intermetallic nanocrystals (NCs) remains a considerable challenge due to the limitation of large volume asymmetry between the components. Here, a series of unconventional intermetallic Frank-Kasper C15 phase Ir2M (M = rare earth metals La, Ce, Gd, Tb, Tm) NCs is successfully prepared via a molten-salt assisted reduction method as efficient electrocatalysts for hydrogen evolution reaction (HER). Compared to the disordered counterpart (A1-Ir2Ce), C15-Ir2Ce features higher Ir-Ce coordination number that leads to an electron-rich environment for Ir sites. The C15-Ir2Ce catalyst exhibits excellent and pH-universal HER activity and requires only 9, 16, and 27 mV overpotentials to attain 10 mA cm-2 in acidic, alkaline, and neutral electrolytes, respectively, representing one of the best HER electrocatalysts ever reported. In a proton exchange membrane water electrolyzer, the C15-Ir2Ce cathode achieves an industrial-scale current density of 1 A cm-2 with a remarkably low cell voltage of 1.7 V at 80 °C and can operate stably for 1000 h with a sluggish voltage decay rate of 50 µV h-1. Theoretical investigations reveal that the electron-rich Ir sites intensify the polarization of *H2O intermediate on C15-Ir2Ce, thus lowering the energy barrier of the water dissociation and facilitating the HER kinetics.

6.
Br J Clin Pharmacol ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39305011

RESUMEN

AIMS: This study aimed to investigate the association between use of proton pump inhibitors (PPI) and frailty index (FI), and to assess the causality relationship using Mendelian randomization (MR). METHODS: A total of 9756 middle-aged and older adults from the National Health and Nutrition Examination Survey were included. The FI was evaluated using a previously validated 49-item deficit model to assess frailty status, which is one of the common approaches to measure overall health burden. We performed weighted multivariable-adjusted linear regression to assess the association between PPI use and FI, and conducted a two-sample MR to evaluate causality, employing various sensitivity analyses for robustness. The inverse variance weighted (IVW) method was used as the primary analysis. RESULTS: Multiple linear regression analysis revealed a positive association between PPI use and FI (ß = 0.048, 95% confidence interval [CI]: 0.042-0.054, P < .001). This association was observed in both short-term (≤ 1 year) and long-term (> 1 year) PPI users (P for trend < 0.001). The MR study also revealed a positive association between PPI use and FI based on the IVW method (ß = 1.183, 95% CI: 0.474-1.892, P = .001). CONCLUSIONS: While our findings suggest a potential link between PPI use and FI, they should be interpreted with caution due to the study's limitations. Although the MR analysis suggests a causal relationship, further research, particularly longitudinal studies, is needed to confirm these findings and better establish temporality.

7.
Artículo en Inglés | MEDLINE | ID: mdl-39307323

RESUMEN

PURPOSE: Online adaptive proton therapy (oAPT) is essential to address interfractional anatomical changes in patients receiving pencil beam scanning proton therapy (PBSPT). Artificial intelligence (AI)-based auto-segmentation can increase the efficiency and accuracy. Linear energy transfer (LET)-based biological effect evaluation can potentially mitigate possible adverse events caused by high LET. New spot arrangement based on the verification CT (vCT) can further improve the re-plan quality. We propose an oAPT workflow that incorporates all these functionalities and validate its clinical implementation feasibility with prostate patients. METHODS AND MATERIALS: AI-based auto-segmentation tool AccuContourTM (Manteia, Xiamen, China) was seamlessly integrated into oAPT. Initial spot arrangement tool on the vCT for re-optimization was implemented using raytracing. An LET-based biological effect evaluation tool was developed to assess the overlap region of high dose and high LET in selected OARs. Eleven prostate cancer patients were retrospectively selected to verify the efficacy and efficiency of the proposed oAPT workflow. The time cost of each component in the workflow was recorded for analysis. RESULTS: The verification plan showed significant degradation of the CTV coverage and rectum and bladder sparing due to the interfractional anatomical changes. Re-optimization on the vCT resulted in great improvement of the plan quality. No overlap regions of high dose and high LET distributions were observed in bladder or rectum in re-plans. 3D Gamma analyses in PSQA confirmed the accuracy of the re-plan doses before delivery (Gamma passing rate = 99.57 ± 0.46%), and after delivery (98.59 ± 1.29%). The robustness of the re-plans passed all clinical requirements. The average time for the complete execution of the workflow was 9.12 ± 0.85 minutes, excluding manual intervention time. CONCLUSION: The AI-facilitated oAPT workflow was demonstrated to be both efficient and effective by generating a re-plan that significantly improved the plan quality in prostate cancer treated with PBSPT.

8.
Cancer Radiother ; 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39307604

RESUMEN

PURPOSE: X-ray and proton irradiation have been reported to induce distinct modifications in cytokine expression in vitro and in vivo, suggesting a dissimilar inflammatory response between X-rays and protons. We aimed to investigate the differences in cytokine profiles early following fractionated brain irradiation with X-rays or protons and their relationship with leukocyte subpopulations in rodents. MATERIALS AND METHODS: Our study utilized data from 80 tumor-free mice subjected to X-ray or proton brain irradiation in four fractions of 2.5Gy. Sixteen non-irradiated mice were used as the controls. Blood was collected 12h postirradiation to examine the profile of 13 cytokines. Correlation analysis, principal component analysis (PCA), and tree-based modeling were used to investigate the relationship between cytokine levels and leukocyte subpopulation variations following irradiation in the blood. RESULTS: Regardless of the irradiation type, brain irradiation resulted in a notable elevation in the plasma levels of IFN-γ and MCP-1. The use of either X-ray or proton beam had differential effect on plasma cytokine levels following brain irradiation. Specifically, X-ray irradiation was associated with significantly increased plasma levels of IFN-ß, IL-12p70, and IL-23, along with a decreased level of IL-1α, in comparison to proton irradiation. Correlation analysis revealed distinct cytokine regulatory patterns between X-ray and proton brain irradiation. PCA highlighted the association of MCP-1, IL-6, TNF-α, IL-17A, and IFN-γ with neutrophils, monocytes, and naïve T-cells following X-ray irradiation. TNF-α and IL-23 levels correlated with naïve CD4+-cells following proton irradiation. Tree-based models demonstrated that high TNF-α level resulted in an increase in naïve T-cells, neutrophils, and monocytes, whereas low IL-6 level was associated with decreases in these cell counts. CONCLUSION: Our findings revealed distinct inflammatory responses induced by X-ray irradiation in contrast to proton brain irradiation, as demonstrated by the differential regulation of cytokines in the bloodstream. Moreover, the study highlighted the association between specific cytokine levels and various leukocyte subpopulations. Further investigation is essential to accurately determine the impact of proton and X-ray brain irradiation on the inflammatory response and the efficacy of radiotherapy treatment.

9.
Front Immunol ; 15: 1390025, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39247190

RESUMEN

Proton pump inhibitors (PPIs), such as omeprazole, are the most commonly prescribed drugs. Treatment with PPIs alters gut microbiota composition and reduces the production of reactive oxygen (ROS) and proinflammatory IL-1ß, IL-6, and TNF-α cytokines. Here, using the T cell-dependent contact hypersensitivity (CHS) response, an animal model of allergic contact dermatitis (ACD) that affects up to 30% of the population, we demonstrated that a two-week omeprazole treatment suppresses the development of CHS. Omeprazole treatment before CHS induction, reduced inflammatory response in ears measured by ear swelling, ear biopsy weight, MPO activity, and proinflammatory cytokine production. These changes were associated with reduced frequency of TCRαß+ CD4+ IL-17A+ and TCRαß+ CD8+ IL-17A+ T cells and increased frequency of TCRαß+ CD4+ CD25+ FoxP3+ Treg, and TCRαß+ CD4+ IL-10+ Tr1 cells in peripheral lymphoid organs. Omeprazole treatment decreased the production of ROS, TNF-α, and IL-6, which supported Th17 cell induction, and increased the frequency of Clostridium cluster XIVab and Lactobacillus, implicated in Treg cell induction. The fecal microbiota transplantation (FMT) experiment confirmed the role of omeprazole-induced changes in gut microbiota profile in CHS suppression. Our data suggests that omeprazole ameliorates inflammatory response mediated by T-cells.


Asunto(s)
Disbiosis , Microbioma Gastrointestinal , Omeprazol , Inhibidores de la Bomba de Protones , Linfocitos T Reguladores , Células Th17 , Animales , Inhibidores de la Bomba de Protones/efectos adversos , Inhibidores de la Bomba de Protones/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/inmunología , Células Th17/inmunología , Células Th17/metabolismo , Ratones , Linfocitos T Reguladores/inmunología , Omeprazol/farmacología , Modelos Animales de Enfermedad , Citocinas/metabolismo , Femenino , Ratones Endogámicos C57BL , Dermatitis por Contacto/inmunología , Dermatitis por Contacto/etiología
10.
Magn Reson Med ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250517

RESUMEN

PURPOSE: This goal of this study was to optimize spectrally selective 1H-MRS methods for large-volume acquisition of low-concentration metabolites with downfield resonances at 7 T and 3 T, with particular attention paid to detection of nicotinamide adenine dinucleotide (NAD+) and tryptophan. METHODS: Spectrally selective excitation was used to avoid magnetization-transfer effects with water, and various sinc pulses were compared with a band-selective, uniform response, pure-phase (E-BURP) pulse. Localization using a single-slice selective pulse was compared with voxel-based localization that used three orthogonal refocusing pulses, and low bandwidth refocusing pulses were used to take advantage of the chemical shift displacement of water. A technique for water sideband removal was added, and a method of coil channel combination for large volumes was introduced. RESULTS: Proposed methods were compared qualitatively with previously reported techniques at 7 T. Sinc pulses resulted in reduced water signal excitation and improved spectral quality, with a symmetric, low bandwidth-time product pulse performing best. Single-slice localization allowed shorter TEs with large volumes, enhancing signal, whereas low-bandwidth slice-selective localization greatly reduced the observed water signal. Gradient cycling helped remove water sidebands, and frequency aligning and pruning individual channels narrowed spectral linewidths. High-quality brain spectra of NAD+ and tryptophan are shown in 4 subjects at 3 T. CONCLUSION: Improved spectral quality with higher downfield signal, shorter TE, lower nuisance signal, reduced artifacts, and narrower peaks was realized at 7 T. These methodological improvements allowed for previously unachievable detection of NAD+ and tryptophan in human brain at 3 T in under 5 min.

11.
Cancers (Basel) ; 16(17)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39272874

RESUMEN

Radiotherapy is one of the main cancer treatments being used for ~50% of all cancer patients. Conventional radiotherapy typically utilises X-rays (photons); however, there is increasing use of particle beam therapy (PBT), such as protons and carbon ions. This is because PBT elicits significant benefits through more precise dose delivery to the cancer than X-rays, but also due to the increases in linear energy transfer (LET) that lead to more enhanced biological effectiveness. Despite the radiotherapy type, the introduction of DNA damage ultimately drives the therapeutic response through stimulating cancer cell death. To combat this, cells harbour cell cycle checkpoints that enables time for efficient DNA damage repair. Interestingly, cancer cells frequently have mutations in key genes such as TP53 and ATM that drive the G1/S checkpoint, whereas the G2/M checkpoint driven through ATR, Chk1 and Wee1 remains intact. Therefore, targeting the G2/M checkpoint through specific inhibitors is considered an important strategy for enhancing the efficacy of radiotherapy. In this review, we focus on inhibitors of Chk1 and Wee1 kinases and present the current biological evidence supporting their utility as radiosensitisers with different radiotherapy modalities, as well as clinical trials that have and are investigating their potential for cancer patient benefit.

12.
J Pak Med Assoc ; 74(9): 1718-1720, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39279088

RESUMEN

Chordomas are rare malignant neoplasms arising from vestigial remnants of the embryonic notochord. Approximately 55-70% of chordomas develop within the vertebral column. Their affinity to develop within the bones of the axial skeleton and propensity to locally invade and recur makes them challenging candidates for complete surgical excision. Adjuvant therapies are hence necessary to improve outcomes; for which chemotherapy has been observed to be largely ineffective, owing to the tumour being resistant to it. Radiotherapy is the current adjuvant therapy of choice for chordoma management. Over the years, proton beam therapy (PBT) has been the subject of medical attention, given the dosimetric benefits it confers over traditional radiotherapy, allowing more concentrated radiation to be given to the target of interest and reducing damage to surrounding normal tissue. A review of the current literature reveals PBT offers significantly better outcomes when used as an adjuvant to maximal surgical resection rather than as a definitive therapy.


Asunto(s)
Cordoma , Terapia de Protones , Neoplasias de la Columna Vertebral , Humanos , Cordoma/radioterapia , Terapia de Protones/métodos , Neoplasias de la Columna Vertebral/radioterapia , Radioterapia Adyuvante/métodos
13.
Endokrynol Pol ; 75(4): 359-365, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39279305

RESUMEN

Proton pump inhibitors (PPIs) are one of the most frequently used medications worldwide. The side effects of this class of drugs have been widely studied. However, their impact on the electrolyte balance is frequently forgotten. Long-term PPI administration can lead to profound electrolyte disturbances, namely hypomagnesaemia as well as, secondary to very low magnesium levels, hypocalcaemia and hypokalaemia. In this paper we comprehensively review the complexity of the mechanisms contributing to electrolyte imbalance following PPI (proton pump inhibitors) by changing the pH in the intestinal lumen, interfering with the active cellular transport of magnesium regulated by the transient receptor potential melastatin cation channels TRPM6 and TRPM7. The accompanying hypomagnesaemia causes unblocking of the renal outer medullary potassium channel (ROMK), which results in increased potassium loss in the ascending limb of the loop of Henle. Hypokalaemia caused by hypomagnesaemia is resistant to potassium supplementation because the loss of this element in urine increases with the supply of potassium. Additionally, within the calcium-sensitive receptor (CASR), dissociation of magnesium from the alpha subunit of G protein caused by hypomagnesaemia increases its activity, leading to inhibition of PTH secretion and hypocalcaemia resistant to calcium supplementation. All this means that in some patients, chronic use of proton pump inhibitors by affecting the absorption of magnesium, may lead to life-threatening electrolyte disorders.


Asunto(s)
Hipocalcemia , Hipopotasemia , Inhibidores de la Bomba de Protones , Inhibidores de la Bomba de Protones/efectos adversos , Humanos , Hipocalcemia/inducido químicamente , Hipopotasemia/inducido químicamente , Magnesio/metabolismo , Magnesio/sangre , Deficiencia de Magnesio/inducido químicamente , Femenino , Masculino
14.
Anal Bioanal Chem ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283368

RESUMEN

Modern mass spectrometry technology allows for extensive sequencing of the ~ 25 kDa subunits of monoclonal antibodies (mAbs) produced by IdeS proteolysis followed by disulfide bond reduction, an approach known as middle-down mass spectrometry (MD MS). However, the spectral congestion of tandem mass spectra of large polypeptides dramatically complicates fragment ion assignment. Here, we report the development and benchmark of an MD MS strategy based on the combination of different ion fragmentation techniques with proton transfer charge reduction (PTCR) to simplify the gas-phase sequencing of mAb subunits. Applied on the liquid chromatography time scale using an Orbitrap Tribrid mass spectrometer, PTCR produces easy-to-interpret mass spectra with limited ion signal overlap. We demonstrate that the accurate estimation of the number of charges submitted to the Orbitrap mass analyzer after PTCR allows for the detection of charge-reduced product ions over a wide mass-over-charge (m/z) window with low parts per million m/z accuracy. Therefore, PTCR-based MD MS analysis increases not only sequence coverage, number of uniquely identified fragments, and number of assigned complementary ion pairs, but also the general confidence in the assignment of subunit fragments. This data acquisition method can be readily applied to any class of mAbs without an apparent need for optimization, and benefits from the high resolving power of the Orbitrap mass analyzer to return sequence coverage of individual subunits exceeding 80% in a single run, and > 90% when just two experiments are combined.

15.
J Appl Clin Med Phys ; : e14525, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284227

RESUMEN

PURPOSE: In the modeling of beam data for proton therapy planning systems, absolute dose measurements are performed utilizing a Bragg peak chamber (BPC), which is a parallel-plate ionization chamber. The long-term stability of the BPC is crucial for ensuring accurate absolute dose measurement. The study aims to assess the long-term stability of the BPC in clinical proton pencil beam scanning delivery. METHODS: The long-term stability evaluation focused on the BPC-Type 34070 (PTW Freiburg, Germany), utilizing clinical proton scanning beams from December 2022 to November 2023. Monthly investigations were conducted to evaluate the response and cross-calibration factor of the BPC and a reference chamber, employing the spread-out Bragg peak (SOBP) field. Additionally, assessments were made regarding the BPC's response to monoenergetic beams, along with an examination of the impact of polarity and ion recombination on the BPC. RESULTS: The response and cross-calibration factor of the BPC varied up to 1.9% and 1.8%, respectively, while the response of the reference chamber remained within a 0.5% range. The BPC's response to the mono-energetic beams varied up to 2.0% across all energies, demonstrating similar variation trends in both the SOBP field and mono-energetic beams. Furthermore, the variations in polarity and ion recombination effect remained stable within a 0.4% range throughout the year. Notably, the reproducibility of the BPC remained high for each measurement conducted, whether for the SOBP field or mono-energetic beams, with a maximum deviation observed at 0.1%. CONCLUSIONS: The response and cross-calibration factor of the BPC demonstrated significant variations, with maximum changes of 1.9% and 1.8%, respectively. However, the reproducibility of the BPC remained consistently high for each measurement. It is recommended that when conducting absolute dose measurements using a BPC, its response should be compared and corrected against the reference chamber for each measurement.

16.
Proc Natl Acad Sci U S A ; 121(37): e2405236121, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39226362

RESUMEN

Electrochemical ammonia (NH3) synthesis from nitrate reduction (NITRR) offers an appealing solution for addressing environmental concerns and the energy crisis. However, most of the developed electrocatalysts reduce NO3- to NH3 via a hydrogen (H*)-mediated reduction mechanism, which suffers from undesired H*-H* dimerization to H2, resulting in unsatisfactory NH3 yields. Herein, we demonstrate that reversed I1Cu4 single-atom sites, prepared by anchoring iodine single atoms on the Cu surface, realized superior NITRR with a superior ammonia yield rate of 4.36 mg h-1 cm-2 and a Faradaic efficiency of 98.5% under neutral conditions via a proton-coupled electron transfer (PCET) mechanism, far beyond those of traditional Cu sites (NH3 yield rate of 0.082 mg h-1 cm-2 and Faradaic efficiency of 36.5%) and most of H*-mediated NITRR electrocatalysts. Theoretical calculations revealed that I single atoms can regulate the local electronic structures of adjacent Cu sites in favor of stronger O-end-bidentate NO3- adsorption with dual electron transfer channels and suppress the H* formation from the H2O dissociation, thus switching the NITRR mechanism from H*-mediated reduction to PCET. By integrating the monolithic I1Cu4 single-atom electrode into a flow-through device for continuous NITRR and in situ ammonia recovery, an industrial-level current density of 1 A cm-2 was achieved along with a NH3 yield rate of 69.4 mg h-1 cm-2. This study offers reversed single-atom sites for electrochemical ammonia synthesis with nitrate wastewater and sheds light on the importance of switching catalytic mechanisms in improving the performance of electrochemical reactions.

17.
Artículo en Inglés | MEDLINE | ID: mdl-39292614

RESUMEN

Intramolecular hydrogen bonding (H-bonding) involved in the excited-state proton transfer (ESPT) process results in benzophenone derivatives (BPDs) with an excellent ability to passivate defects. However, the BPDs are in a continuing dynamic transition process between the ground state and the excited state under light radiation conditions. The ground-state BPDs may lose their ability to passivate defects, resulting in an increased defect density of the perovskite. Therefore, enhancing the passivation ability of the ground-state BPDs can help to achieve the full passivation ability of their ground state to excited state. Herein, we have researched the various BPDs by density functional theory and found that intramolecular H-bonding can weaken the passivation ability of ground-state BPDs, but intramolecular H-bonding is indispensable in the ESPT process. To address the issue, we investigated the influence of electron-donor properties and dipole moments of hydroxyl (-OH), methoxy (-OCH3), and n-octyloxy (-OC8H17) groups in BPD molecules on their coordination capacity through molecular design engineering. Ultimately, 2-hydroxy-4-n-octyloxy-benzophenone (UV5) with strong electron-donor n-octyloxy (-OC8H17) and elongated carbon-chain structure was selected as an additive, which enhances the passivate defect capability in both the ground and excited states. As a result, the UV5-based champion device achieved a power conversion efficiency (PCE) of 24.46% and remained at 75% of the initial PCE with exposure to UV light. This work focuses on the defect passivation capability of ground-state BPDs for the first time and opens a new concept for applying BPDs in PSCs.

18.
Eur J Med Res ; 29(1): 466, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300586

RESUMEN

OBJECTIVES: To assess the efficacy of the Chinese herbal medication Shugan Hewei formula (SHF) combined with rabeprazole in patients with refractory gastroesophageal reflux disease (rGERD). METHOD: A total of 264 participants were randomly assigned to the treatment group (n = 132) receiving SHF granules (20 mg) combined with rabeprazole (10 mg) and the control group (n = 132) receiving placebo SHF granules (20 mg) combined with rabeprazole (20 mg). Both groups undergo 8 weeks of treatment and 2 weeks of follow-up. RESULTS: The treatment group showed higher total clinical symptom efficacy and lower total symptom scores compared to the control group. The treatment group was superior to the control group in reducing rGERD major symptom scores, including heartburn, retrosternal pain, regurgitation and belching, and acid regurgitation. Additionally, treatment group (Z = 8.169, P < 0.001) and control group (Z = 9.800, P < 0.001) treatments were all significantly attenuated esophageal inflammation, demonstrating comparable efficacy. Patients with esophagitis grade A decreased from 40.34% to 17.23%, and those with grade B decreased from 11.76% to 3.78% in the treatment group. The results of the SF-36 scale showed that combination therapy was more effective in improving role limitations due to physical health, vitality, general health, total somato-physical health, and psychiatric mental health. CONCLUSION: Our study reveals that the combined treatment of SHF with rabeprazole is more efficacious in managing patients with rGERD when contrasted with sole rabeprazole treatment.


Asunto(s)
Medicamentos Herbarios Chinos , Reflujo Gastroesofágico , Rabeprazol , Humanos , Rabeprazol/administración & dosificación , Rabeprazol/uso terapéutico , Reflujo Gastroesofágico/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/administración & dosificación , Femenino , Adulto , Método Doble Ciego , Resultado del Tratamiento , Quimioterapia Combinada/métodos
19.
Front Nutr ; 11: 1436993, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39301419

RESUMEN

Background and aims: Vonoprazan, a novel acid suppressant, has been employed in the treatment of peptic ulcer disease in recent years. However, the efficacy and safety of vonoprazan versus proton-pump inhibitors remains controversial. To address this gap, a systematic review and network meta-analysis were conducted to evaluate the efficacy and safety of vonoprazan in comparison with various proton-pump inhibitors. Methods: Randomized controlled trials that met selection criteria in PubMed (Medline), EMBASE and the Cochrane Library were searched up to July 15, 2024. The primary outcome was ulcer healing rate. Secondary outcomes were treatment-emergent adverse events and drug-related adverse events. Effect size on outcomes is presented as odds ratios with 95% confidence intervals. Results: Thirty-five randomized controlled trials containing 9,544 participants were included. In terms of the healing rate at 2 weeks, lansoprazole 30 mg ranked first, followed by vonoprazan 20 mg and ilaprazole 10 mg. In terms of the healing rate at 4 weeks, pantoprazole 40 mg ranked first, with rabeprazole 10 mg and lansoprazole 30 mg ranking second and third, respectively. Regarding the healing rate at 8 weeks, lansoprazole 30 mg is demonstrated to be the most efficacious regimen. Moreover, subgroup analysis indicated that lansoprazole 30 mg is the optimal regimen in the treatment of artificial gastric ulcer at 4 and 8 weeks. Importantly, lansoprazole 30 mg has fewer adverse reactions and higher safety. Conclusion: The optimal regimen for the treatment of peptic ulcer disease may be lansoprazole 30 mg at 2 and 8 weeks, while pantoprazole 40 mg has demonstrated superior performance at the 4-week when compared to vonoprazan 20 mg. Furthermore, lansoprazole 30 mg has shown to be superior in terms of safety outcomes. These findings, derived from a network meta-analysis, necessitate further research for validation.

20.
Appl Radiat Isot ; 214: 111515, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39276639

RESUMEN

Boron Neutron Capture Therapy is being promoted with the development of accelerator neutron sources, and many new accelerator-based BNCT facilities are being built. In Particle Accelerator Facility project of Sun Yat-sen University, we plan to build a terminal for BNCT research based on an 8 MeV, CW 3 mA proton accelerator. In this paper, we present a beam-shaping assembly for this proton accelerator with such low 24 kW beam power, using composite moderator materials composed of five elements: Mg, Al, F, O, and Li. The calculation result of FLUKA with ENDF/B and JENDL libraries shows that the epithermal neutron beam flux is 1.57×109n/cm2/s with the CW 3 mA proton beam. The fast neutron component and the gamma ray component under free-air condition are 1.49×10-13Gy∙cm2 and 8.12×10-14Gy∙cm2 respectively, in line with IAEA-TECDOC-1223 design recommendations. The thermal analysis shows that the maximum temperature of beryllium target is 706.5 K, and the structure materials of BSA do not melt.

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