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1.
Nature ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866052

RESUMEN

Increasing planting density is a key strategy to enhance maize yields1-3. An ideotype for dense planting requires a 'smart canopy' with leaf angles at different canopy layers differentially optimized to maximize light interception and photosynthesis4-6, amongst other features. Here, we identified leaf angle architecture of smart canopy 1 (lac1), a natural mutant possessing upright upper leaves, less erect middle leaves and relatively flat lower leaves. lac1 has improved photosynthetic capacity and weakened shade-avoidance responses under dense planting. lac1 encodes a brassinosteroid C-22 hydroxylase that predominantly regulates upper leaf angle. Phytochrome A photoreceptors accumulate in shade and interact with the transcription factor RAVL1 to promote its degradation via the 26S proteasome, thereby attenuating RAVL1 activation of lac1 and reducing brassinosteroid levels. This ultimately decreases upper leaf angle in dense fields. Large-scale field trials demonstrate lac1 boosts maize yields under high densities. To quickly introduce lac1 into breeding germplasm, we transformed a haploid inducer and recovered homozygous lac1 edits from 20 diverse inbred lines. The tested doubled haploids uniformly acquired smart-canopy-like plant architecture. We provide an important target and an accelerated strategy for developing high-density-tolerant cultivars, with lac1 serving as a genetic chassis for further engineering of a smart canopy in maize.

2.
Proc Natl Acad Sci U S A ; 120(15): e2208676120, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37014856

RESUMEN

Two-dimensional (2D) covalent-organic frameworks (COFs) with a well-defined and tunable periodic porous skeleton are emerging candidates for lightweight and strong 2D polymeric materials. It remains challenging, however, to retain the superior mechanical properties of monolayer COFs in a multilayer stack. Here, we successfully demonstrated a precise layer control in synthesizing atomically thin COFs, enabling a systematic study of layer-dependent mechanical properties of 2D COFs with two different interlayer interactions. It was shown that the methoxy groups in COFTAPB-DMTP provided enhanced interlayer interactions, leading to layer-independent mechanical properties. In sharp contrast, mechanical properties of COFTAPB-PDA decreased significantly as the layer number increased. We attributed these results to higher energy barriers against interlayer sliding due to the presence of interlayer hydrogen bonds and possible mechanical interlocking in COFTAPB-DMTP, as revealed by density functional theory calculations.

3.
Mol Cell ; 65(6): 985-998.e6, 2017 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-28262506

RESUMEN

Several prokaryotic Argonaute proteins (pAgos) utilize small DNA guides to mediate host defense by targeting invading DNA complementary to the DNA guide. It is unknown how these DNA guides are being generated and loaded onto pAgo. Here, we demonstrate that guide-free Argonaute from Thermus thermophilus (TtAgo) can degrade double-stranded DNA (dsDNA), thereby generating small dsDNA fragments that subsequently are loaded onto TtAgo. Combining single-molecule fluorescence, molecular dynamic simulations, and structural studies, we show that TtAgo loads dsDNA molecules with a preference toward a deoxyguanosine on the passenger strand at the position opposite to the 5' end of the guide strand. This explains why in vivo TtAgo is preferentially loaded with guides with a 5' end deoxycytidine. Our data demonstrate that TtAgo can independently generate and selectively load functional DNA guides.


Asunto(s)
Proteínas Argonautas/metabolismo , Proteínas Bacterianas/metabolismo , ADN sin Sentido/metabolismo , ADN Bacteriano/metabolismo , Thermus thermophilus/enzimología , Proteínas Argonautas/química , Proteínas Argonautas/genética , Proteínas Bacterianas/genética , Sitios de Unión , ADN sin Sentido/química , ADN sin Sentido/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Desoxicitidina/metabolismo , Desoxiguanosina/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Simulación de Dinámica Molecular , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica , Imagen Individual de Molécula , Relación Estructura-Actividad , Thermus thermophilus/genética
4.
Eur Heart J ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38607560

RESUMEN

BACKGROUND AND AIMS: Patients with acute myeloid leukaemia (AML) suffer from severe myocardial injury during daunorubicin (DNR)-based chemotherapy and are at high risk of cardiac mortality. The crosstalk between tumour cells and cardiomyocytes might play an important role in chemotherapy-related cardiotoxicity, but this has yet to be demonstrated. This study aimed to identify its underlying mechanism and explore potential therapeutic targets. METHODS: Cardiac tissues were harvested from an AML patient after DNR-based chemotherapy and were subjected to single-nucleus RNA sequencing. Cardiac metabolism and function were evaluated in AML mice after DNR treatment by using positron emission tomography, magnetic resonance imaging, and stable-isotope tracing metabolomics. Plasma cytokines were screened in AML mice after DNR treatment. Genetically modified mice and cell lines were used to validate the central role of the identified cytokine and explore its downstream effectors. RESULTS: In the AML patient, disruption of cardiac metabolic homeostasis was associated with heart dysfunction after DNR-based chemotherapy. In AML mice, cardiac fatty acid utilization was attenuated, resulting in cardiac dysfunction after DNR treatment, but these phenotypes were not observed in similarly treated tumour-free mice. Furthermore, tumour cell-derived interleukin (IL)-1α was identified as a primary factor leading to DNR-induced cardiac dysfunction and administration of an anti-IL-1α neutralizing antibody could improve cardiac functions in AML mice after DNR treatment. CONCLUSIONS: This study revealed that crosstalk between tumour cells and cardiomyocytes during chemotherapy could disturb cardiac energy metabolism and impair heart function. IL-1α neutralizing antibody treatment is a promising strategy for alleviating chemotherapy-induced cardiotoxicity in AML patients.

5.
Nano Lett ; 24(8): 2465-2472, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38349857

RESUMEN

The rich morphology of 2D materials grown through chemical vapor deposition (CVD), is a distinctive feature. However, understanding the complex growth of 2D crystals under practical CVD conditions remains a challenge due to various intertwined factors. Real-time monitoring is crucial to providing essential data and enabling the use of advanced tools like machine learning for unraveling these complexities. In this study, we present a custom-built miniaturized CVD system capable of observing and recording 2D MoS2 crystal growth in real time. Image processing converts the real-time footage into digital data, and machine learning algorithms (ML) unveil the significant factors influencing growth. The machine learning model successfully predicts CVD growth parameters for synthesizing ultralarge monolayer MoS2 crystals. It also demonstrates the potential to reverse engineer CVD growth parameters by analyzing the as-grown 2D crystal morphology. This interdisciplinary approach can be integrated to enhance our understanding of controlled 2D crystal synthesis through CVD.

6.
Nano Lett ; 24(17): 5182-5188, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38630435

RESUMEN

Bismuth halide perovskites are widely regarded as nontoxic alternatives to lead halide perovskites for optoelectronics and solar energy harvesting applications. With a tailorable composition and intriguing optical properties, bismuth halide perovskites are also promising candidates for tunable photonic devices. However, robust control of the anion composition in bismuth halide perovskites remains elusive. Here, we established chemical vapor deposition and anion exchange protocols to synthesize bismuth halide perovskite nanoflakes with controlled dimensions and variable compositions. In particular, we demonstrated the gradient bromide distribution by controlling the anion exchange and diffusion processes, which is spatially resolved by time-of-flight secondary ion mass spectrometry. Moreover, the optical waveguiding properties of bismuth halide perovskites can be modulated by flake thicknesses and anion compositions. With a unique gradient anion distribution and controllable optical properties, bismuth halide perovskites provide new possibilities for applications in optoelectronic devices and integrated photonics.

7.
J Am Chem Soc ; 146(18): 12850-12856, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38648558

RESUMEN

Acetylene production from mixed α-olefins emerges as a potentially green and energy-efficient approach with significant scientific value in the selective cleavage of C-C bonds. On the Pd(100) surface, it is experimentally revealed that C2 to C4 α-olefins undergo selective thermal cleavage to form surface acetylene and hydrogen. The high selectivity toward acetylene is attributed to the 4-fold hollow sites which are adept at severing the terminal double bonds in α-olefins to produce acetylene. A challenge arises, however, because acetylene tends to stay at the Pd(100) surface. By using the surface alloying methodology with alien Au, the surface Pd d-band center has been successfully shifted away from the Fermi level to release surface-generated acetylene from α-olefins as a gaseous product. Our study actually provides a technological strategy to economically produce acetylene and hydrogen from α-olefins.

8.
Cancer ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38642373

RESUMEN

BACKGROUND: Supportive oncology (SO) care reduces symptom severity, admissions, and costs in patients with advanced cancer. This study examines the impact of SO care on utilization and costs. METHODS: Retrospective analysis of utilization and costs comparing patients enrolled in SO versus three comparison cohorts who did not receive SO. Using claims, the authors estimated differences in health care utilization and cost between the treatment group and comparison cohorts. The treatment group consisting of patients treated for cancer at an National Cancer Institute-designated cancer center who received SO between January 2018 and December 2019 were compared to an asynchronous cohort that received cancer care before January 2018 (n = 60), a contemporaneous cohort with palliative care receiving SO care from other providers in the Southeastern Pennsylvania region during the program period (n = 86), and a contemporaneous cohort without palliative care consisting of patients at other cancer centers who were eligible for but did not receive SO care (n = 393). RESULTS: At 30, 60, and 90 days post-enrollment into SO, the treatment group had between 27% and 70% fewer inpatient admissions and between 16% and 54% fewer emergency department visits (p < .05) compared to non-SO cohorts. At 90 days following enrollment in SO care, total medical costs were between 4.4% and 24.5% lower for the treatment group across all comparisons (p < .05). CONCLUSIONS: SO is associated with reduced admissions, emergency department visits, and total costs in advanced cancer patients. Developing innovative reimbursement models could be a cost-effective approach to improve care of patients with advanced cancer.

9.
Small ; : e2310562, 2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38431932

RESUMEN

In recent years, there has been a substantial surge in the investigation of transition-metal dichalcogenides such as MoS2 as a promising electrochemical catalyst. Inspired by denitrification enzymes such as nitrate reductase and nitrite reductase, the electrochemical nitrate reduction catalyzed by MoS2 with varying local atomic structures is reported. It is demonstrated that the hydrothermally synthesized MoS2 containing sulfur vacancies behaves as promising catalysts for electrochemical denitrification. With copper doping at less than 9% atomic ratio, the selectivity of denitrification to dinitrogen in the products can be effectively improved. X-ray absorption characterizations suggest that two sulfur vacancies are associated with one copper dopant in the MoS2 skeleton. DFT calculation confirms that copper dopants replace three adjacent Mo atoms to form a trigonal defect-enriched region, introducing an exposed Mo reaction center that coordinates with Cu atom to increase N2 selectivity. Apart from the higher activity and selectivity, the Cu-doped MoS2 also demonstrates remarkably improved tolerance toward oxygen poisoning at high oxygen concentration. Finally, Cu-doped MoS2 based catalysts exhibit very low specific energy consumption during the electrochemical denitrification process, paving the way for potential scale-up operations.

10.
Am Heart J ; 269: 131-138, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38128898

RESUMEN

BACKGROUND: Nearly 20% Patients with cyanotic congenital heart disease (CCHD) are not able to receive surgery. These patients experience a decline in cardiac function as they age, which has been demonstrated to be associated with changes in energy metabolism in cardiomyocytes. Trimetazidine (TMZ), a metabolic regulator, is supposed to alleviate such maladaptation and reserve cardiac function in CCHD patients. METHODS: This is a randomized, double-blind, placebo-controlled clinical trial. Eighty adult CCHD patients will be recruited and randomized to the TMZ (20 mg TMZ 3 times a day for 3 months) or placebo group (placebo 3 times a day for 3 months). The primary outcome is the difference in cardiac ejection fractions (EF) measured by cardiac magnetic resonance (MRI) between baseline and after 3 months of TMZ treatment. The secondary outcomes include TMZ serum concentration, rate of cardiac events, NYHA grading, fingertip SpO2, NT-proBNP levels, 6-minute walking test (6MWT), KCCQ-CSS questionnaire score, echocardiography, ECG, routine blood examination, liver and kidney function test, blood pressure and heart rate. DISCUSSION: This trial is designed to explore whether the application of TMZ in adult CCHD patients can improve cardiac function, reduce cardiac events, and improve exercise performance and quality of life. The results will provide targeted drug therapy for CCHD patients with hypoxia and support the application of TMZ in children with CCHD.


Asunto(s)
Enfermedades Cardiovasculares , Cardiopatías Congénitas , Trimetazidina , Adulto , Niño , Humanos , Trimetazidina/uso terapéutico , Calidad de Vida , Hipoxia/etiología , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/tratamiento farmacológico , Enfermedades Cardiovasculares/tratamiento farmacológico , Método Doble Ciego , Vasodilatadores/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
11.
Chembiochem ; 25(5): e202300683, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38031246

RESUMEN

Perovskite nanomaterials have recently been exploited for bioimaging applications due to their unique photo-physical properties, including high absorbance, good photostability, narrow emissions, and nonlinear optical properties. These attributes outperform conventional fluorescent materials such as organic dyes and metal chalcogenide quantum dots and endow them with the potential to reshape a wide array of bioimaging modalities. Yet, their full potential necessitates a deep grasp of their structure-attribute relationship and strategies for enhancing water stability through surface engineering for meeting the stringent and unique requirements of each individual imaging modality. This review delves into this evolving frontier, highlighting how their distinctive photo-physical properties can be leveraged and optimized for various bioimaging modalities, including visible light imaging, near-infrared imaging, and super-resolution imaging.


Asunto(s)
Compuestos de Calcio , Nanoestructuras , Óxidos , Puntos Cuánticos , Titanio , Puntos Cuánticos/química , Diagnóstico por Imagen/métodos , Luz
12.
Artículo en Inglés | MEDLINE | ID: mdl-38402460

RESUMEN

BACKGROUND: IgA nephropathy (IgAN) is a major cause of primary glomerulonephritis characterized by mesangial deposits of galactose-deficient IgA1 (Gd-IgA1). Toll-like receptors (TLRs), particularly TLR4 are involved in the pathogenesis of IgAN. The role of gut microbiota on IgAN patients was recently investigated. However, whether gut microbial modifications of Gd-IgA1 through TLR4 play a role in IgAN remains unclear. METHODS: We recruited subjects into four groups, including 48 patients with untreated IgAN, 22 treated IgAN patients (IgANIT), 22 primary membranous nephropathy (MN), and 31 healthy controls (HCs). Fecal samples were collected to analyze changes in gut microbiome. Gd-IgA1 levels, expression of TLR4, B-cell stimulators, and intestinal barrier function were evaluated in all subjects. C57BL/6 mice were treated with a broad-spectrum antibiotic cocktail to deplete the gut microbiota and then gavaged with fecal microbiota transplanted fromclinical subjects of every group. Gd-IgA1 and TLR4 pathway were detected in peripheral blood mononuclear cells (PBMCs) from IgAN and HCs co-incubated with Lipopolysaccharide (LPS) and TLR4 inhibitor. RESULTS: Compared with other three groups, different compositions and decreased diversity demonstrated gut dysbiosis in un-treated IgAN, especially the enrichment of Escherichia -Shigella. Elevated Gd-IgA1 levels were found in un-treated IgAN patients and correlated with gut dysbiosis, TLR4, B-cell stimulators, indexes of intestinal barrier damage, and proinflammatory cytokines. In vivo, mice colonized with gut microbiota from IgAN and IgANIT patients, copied the IgAN phenotype with the activation of TLR4/MyD88/NF-κB pathway, B-cell stimulators in the intestine, and complied with enhanced proinflammatory cytokines. In vitro, LPS activated TLR4/MyD88/NF-κB pathway, B-cell stimulators and proinflammatory cytokines in the PBMCs from IgAN patients, which resulted in overproduction of Gd-IgA1 and inhibited by TLR4 inhibitor. CONCLUSIONS: Our results illustrated that gut-kidney axis was involved in the pathogenesis of IgAN. Gut dysbiosis could stimulate the overproduction of Gd-IgA1 by TLR4 signaling pathway production and B-cell stimulators.

13.
Environ Sci Technol ; 58(26): 11578-11586, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38899536

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are the primary organic carbons in soot. In addition to PAHs with even carbon numbers (PAHeven), substantial odd-carbon PAHs (PAHodd) have been widely observed in soot and ambient particles. Analyzing and understanding the photoaging of these compounds are essential for assessing their environmental effects. Here, using laser desorption ionization mass spectrometry (LDI-MS), we reveal the substantially different photoreactivity of PAHodd from PAHeven in the aging process and their MS detection through their distinct behaviors in the presence and absence of elemental carbon (EC) in soot. During direct photooxidation of organic carbon (OC) alone, the PAHeven are oxidized more rapidly than the PAHodd. However, the degradation of PAHodd becomes preponderant over PAHeven in the presence of EC during photoaging of the whole soot. All of these observations are proposed to originate from the more rapid hydrogen abstraction reaction from PAHodd in the EC-photosensitized reaction, owing to its unique structure of a single sp3-hybridized carbon site. Our findings reveal the photoreactivity and reaction mechanism of PAHodd for the first time, providing a comprehensive understanding of the oxidation of PAHs at a molecular level during soot aging and highlight the enhanced effect of EC on PAHodd ionization in LDI-MS analysis.


Asunto(s)
Carbono , Hidrocarburos Policíclicos Aromáticos , Hollín , Hidrocarburos Policíclicos Aromáticos/química , Carbono/química , Hollín/química , Procesos Fotoquímicos , Oxidación-Reducción , Fotoquímica
14.
Macromol Rapid Commun ; 45(9): e2300695, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38350418

RESUMEN

Metal halide perovskites have emerged as versatile photocatalysts to convert solar energy for chemical processes. Perovskite photocatalyzed polymerization draws special attention due to its straightforward synthesis process and the ability to create advanced perovskite-polymer nanocomposites. Herein, this work employs Cs3Sb2Br9 perovskite nanoparticles (NPs) as a lead-free photocatalyst for light-controlled atom transfer radical polymerization (ATRP). Cs3Sb2Br9 NPs exhibit high reduction potential and interact with electronegative bromide initiator with Lewis acid Sb sites, enabling efficient photoinduced reduction of initiators and controlled polymerization under blue light irradiation. Methacrylate monomers with various functional groups are successfully polymerized, and the resulting polymer showcased a dispersity (D) as small as 1.27. The living nature of polymerization is confirmed by high chain end fidelity and kinetic studies. Moreover, Cs3Sb2Br9 NPs serve as heterogeneous photocatalysts, demonstrating recyclability and reusability for up to four cycles. This work presents a promising approach to overcome the limitations of lead-based perovskites in photoinduced controlled radical polymerization, offering a sustainable and efficient alternative for the synthesis of well-defined polymeric materials.


Asunto(s)
Antimonio , Compuestos de Calcio , Nanopartículas , Óxidos , Polimerizacion , Titanio , Titanio/química , Óxidos/química , Catálisis , Compuestos de Calcio/química , Nanopartículas/química , Antimonio/química , Procesos Fotoquímicos , Luz
15.
J Asthma ; 61(7): 707-716, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38315158

RESUMEN

Background: The prevalence of childhood asthma and obesity is increasing, while obesity increases the risk and severity of asthma. Lipid metabolism has been considered as an important factor in the pathogenesis of obesity-associated asthma. Stearoyl-CoA desaturase 1 (SCD1) is a rate-limiting enzyme that catalyzes the production of monounsaturated fatty acids (MUFA).Methods: In the present study, the microarray data retrieved from the Gene Expression Comprehensive Database (GEO) was analyzed to further clarify the impact of SCD1 on Mast cell activation related lipid mediators and the correlation between SCD1 and obesity asthma in the population.Results: SCD1 was highly expressed in IgE-activated bone marrow-derived mast cells (BMMCs). Meanwhile, SCD1 was also verified expressed highly in dinitrophenyl human serum albumin (DNP-HAS) stimulated RBL-2H3 cells. The expression of SCD1 was up-regulated in peripheral blood leukocytes of asthmatic children, and was positively correlated with skinfold thickness of upper arm, abdominal skinfold and body mass index (BMI). Inhibition of SCD1 expression significantly suppressed the degranulation, lipid mediator production, as well as the migration ability in DNP-HAS-stimulated RBL-2H3 cells.Conclusion: SCD1 is involved in obese-related asthma through regulating mast cells.


Asunto(s)
Asma , Mastocitos , Estearoil-CoA Desaturasa , Estearoil-CoA Desaturasa/metabolismo , Estearoil-CoA Desaturasa/genética , Mastocitos/inmunología , Mastocitos/metabolismo , Humanos , Niño , Asma/inmunología , Asma/metabolismo , Masculino , Femenino , Animales , Ratones , Obesidad/metabolismo , Ratas , Índice de Masa Corporal
16.
Pharmacoepidemiol Drug Saf ; 33(2): e5756, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38357810

RESUMEN

BACKGROUND: Distinguishing warfarin-related bleeding risk at the bedside remains challenging. Studies indicate that warfarin therapy should be suspended when international normalized ratio (INR) ≥ 4.5, or it may sharply increase the risk of bleeding. We aim to develop and validate a model to predict the high bleeding risk in valve replacement patients during hospitalization. METHOD: Cardiac valve replacement patients from January 2016 to December 2021 across Nanjing First Hospital were collected. Five different machine-learning (ML) models were used to establish the prediction model. High bleeding risk was an INR ≥4.5. The area under the receiver operating characteristic curve (AUC) was used for evaluating the prediction performance of different models. The SHapley Additive exPlanations (SHAP) was used for interpreting the model. We also compared ML with ATRIA score and ORBIT score. RESULTS: A total of 2376 patients were finally enrolled in this model, 131 (5.5%) of whom experienced the high bleeding risk after anticoagulation therapy of warfarin during hospitalization. The extreme gradient boosting (XGBoost) exhibited the best overall prediction performance (AUC: 0.882, confidence interval [CI] 0.817-0.946, Brier score, 0.158) compared to other prediction models. It also shows superior performance compared with ATRIA score and ORBIT score. The top 5 most influential features in XGBoost model were platelet, thyroid stimulation hormone, body surface area, serum creatinine and white blood cell. CONCLUSION: A model for predicting high bleeding risk in valve replacement patients who treated with warfarin during hospitalization was successfully developed by using machine learning, which may well assist clinicians to identify patients at high risk of bleeding and allow timely adjust therapeutic strategies in evaluating individual patient.


Asunto(s)
Anticoagulantes , Warfarina , Humanos , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Válvulas Cardíacas/cirugía , Aprendizaje Automático
17.
Clin Trials ; 21(1): 114-123, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37877356

RESUMEN

INTRODUCTION: Developing alternative approaches to evaluating absolute efficacy of new HIV prevention interventions is a priority, as active-controlled designs, whereby individuals without HIV are randomized to the experimental intervention or an active control known to be effective, are increasing. With this design, however, the efficacy of the experimental intervention to prevent HIV acquisition relative to placebo cannot be evaluated directly. METHODS: One proposed approach to estimate absolute prevention efficacy is to use an HIV exposure marker, such as incident rectal gonorrhea, to infer counterfactual placebo HIV incidence. We formalize a statistical framework for this approach, specify working regression and likelihood-based estimation approaches, lay out three assumptions under which valid inference can be achieved, evaluate finite-sample performance, and illustrate the approach using a recent active-controlled HIV prevention trial. RESULTS: We find that in finite samples and under correctly specified assumptions accurate and precise estimates of counterfactual placebo incidence and prevention efficacy are produced. Based on data from the DISCOVER trial in men and transgender women who have sex with men, and assuming correctly specified assumptions, the estimated prevention efficacy for tenofovir alafenamide plus emtricitabine is 98.1% (95% confidence interval: 96.4%-99.4%) using the working model approach and 98.1% (95% confidence interval: 96.4%-99.7%) using the likelihood-based approach. CONCLUSION: Careful assessment of the underlying assumptions, study of their violation, evaluation of the approach in trials with placebo arms, and advancement of improved exposure markers are needed before the HIV exposure marker approach can be relied upon in practice.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Femenino , Humanos , Masculino , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Incidencia , Funciones de Verosimilitud , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
BMC Med Imaging ; 24(1): 26, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273224

RESUMEN

PURPOSE: To explore the application of contrast-enhanced ultrasound (CEUS) for the diagnosis and grading of bladder urothelial carcinoma (BUC). METHODS: The results of a two-dimensional ultrasound, color Doppler ultrasound and CEUS, were analyzed in 173 bladder lesion cases. The ultrasound and surgical pathology results were compared, and their diagnostic efficacy was analyzed. RESULTS: There were statistically significant differences between BUC and benign lesions in terms of color blood flow distribution intensity and CEUS enhancement intensity (both P < 0.05). The area under the time-intensity curve (AUC), rising slope, and peak intensity of BUC were significantly higher than those of benign lesions (all P < 0.05). The H/T (height H / basal width T)value of 0.63 was the critical value for distinguishing high- and low-grade BUC, had a diagnostic sensitivity of 80.0% and a specificity of 60.0%. CONCLUSION: The combination of CEUS and TIC can help improve the diagnostic accuracy of BUC. There is a statistically significant difference between high- and low-grade BUC in contrast enhancement intensity (P < 0.05); The decrease of H/T value indicates the possible increase of the BUC grade.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Neoplasias de la Vejiga Urinaria/cirugía , Carcinoma de Células Transicionales/diagnóstico por imagen , Carcinoma de Células Transicionales/patología , Vejiga Urinaria/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Ultrasonografía
19.
J Water Health ; 22(6): 967-977, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38935449

RESUMEN

The anaerobic membrane bioreactor (AnMBR) is a promising technology for not only water reclamation but also virus removal; however, the virus removal efficiency of AnMBR has not been fully investigated. Additionally, the removal efficiency estimation requires datasets of virus concentration in influent and effluent, but its monitoring is not easy to perform for practical operation because the virus quantification process is generally time-consuming and requires specialized equipment and trained personnel. Therefore, in this study, we aimed to identify the key, monitorable variables in AnMBR and establish the data-driven models using the selected variables to predict virus removal efficiency. We monitored operational and environmental conditions of AnMBR in Sendai, Japan and measured virus concentration once a week for six months. Spearman's rank correlation analysis revealed that the pH values of influent and mixed liquor suspended solids (MLSS) were strongly correlated with the log reduction value of pepper mild mottle virus, indicating that electrostatic interactions played a dominant role in AnMBR virus removal. Among the candidate models, the random forest model using selected variables including influent and MLSS pH outperformed the others. This study has demonstrated the potential of AnMBR as a viable option for municipal wastewater reclamation with high microbial safety.


Asunto(s)
Reactores Biológicos , Membranas Artificiales , Reactores Biológicos/virología , Anaerobiosis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/virología , Proyectos Piloto , Purificación del Agua/métodos , Purificación del Agua/instrumentación , Tobamovirus/aislamiento & purificación , Japón
20.
Molecules ; 29(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38611807

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) has evolved into a dangerous pathogen resistant to beta-lactam antibiotics (BLAs) and has become a worrisome superbug. In this study, a strategy in which shikimic acid (SA), which has anti-inflammatory and antibacterial activity, is combined with BLAs to restart BLA activity was proposed for MRSA treatment. The synergistic effects of oxacillin combined with SA against oxacillin resistance in vitro and in vivo were investigated. The excellent synergistic effect of the oxacillin and SA combination was confirmed by performing the checkerboard assay, time-killing assay, live/dead bacterial cell viability assay, and assessing protein leakage. SEM showed that the cells in the control group had a regular, smooth, and intact surface. In contrast, oxacillin and SA or the combination treatment group exhibited different degrees of surface collapse. q-PCR indicated that the combination treatment group significantly inhibited the expression of the mecA gene. In vivo, we showed that the combination treatment increased the survival rate and decreased the bacterial load in mice. These results suggest that the combination of oxacillin with SA is considered an effective treatment option for MRSA, and the combination of SA with oxacillin in the treatment of MRSA is a novel strategy.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Animales , Ratones , Ácido Shikímico/farmacología , Monobactamas , Antibióticos Betalactámicos , Oxacilina/farmacología
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