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1.
Pharm Stat ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227179

RESUMEN

The innovative use of real-world data (RWD) can answer questions that cannot be addressed using data from randomized clinical trials (RCTs). While the sponsors of RCTs have a central database containing all individual patient data (IPD) collected from trials, analysts of RWD face a challenge: regulations on patient privacy make access to IPD from all regions logistically prohibitive. In this research, we propose a double inverse probability weighting (DIPW) approach for the analysis sponsor to estimate the population average treatment effect (PATE) for a target population without the need to access IPD. One probability weighting is for achieving comparable distributions in confounders across treatment groups; another probability weighting is for generalizing the result from a subpopulation of patients who have data on the endpoint to the whole target population. The likelihood expressions for propensity scores and the DIPW estimator of the PATE can be written to only rely on regional summary statistics that do not require IPD. Our approach hinges upon the positivity and conditional independency assumptions, prerequisites to most RWD analysis approaches. Simulations are conducted to compare the performances of the proposed method against a modified meta-analysis and a regular meta-analysis.

2.
J Inflamm Res ; 17: 5633-5643, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39219813

RESUMEN

Purpose: Visceral adiposity is a significant risk factor for severe COVID-19. However, the impact of the Chinese visceral adiposity index (CVAI) on the efficacy of SARS-CoV-2 vaccines remains poorly understood. This study aims to explore the impact of CVAI on the production of neutralizing antibodies (NAb) in inactivated SARS-CoV-2 vaccines and the potential mechanism, thereby optimizing vaccination guidance. Methods: In this cross-sectional study, 206 health workers (completed two SARS-CoV-2 vaccination on February 8th and March 10th, 2021, respectively) were recruited. All baseline anthropometric parameters of the participants were collected, and venous blood samples were obtained 6 weeks later to measure peripheral innate immune cells, inflammatory cytokines, and NAb titers against SARS-CoV-2. CVAI were calculated according to the formula and divided participants into two groups depending on CVAI median. Results: The median NAb titer among healthcare workers was 12.94 AU/mL, with an efficacy of 87.86% for the SARS-CoV-2 vaccine. NAb titers were lower in the CVAI dysfunction group than in the CVAI reference group (median: 11.40 AU/mL vs 15.57 AU/mL), the hsCRP levels (median: 0.50 mg/L vs 0.30 mg/L) and peripheral monocyte count (mean: 0.47 × 109/L vs 0.42 × 109/L) in the CVAI dysfunction group were higher than in the CVAI reference group. Additionally, CVAI showed positive correlations with hsCRP, monocytes, lymphocytes, and B-lymphocytes, and a negative correlation with NAb titers. Conclusion: CVAI may inhibit SARS-CoV-2 neutralizing antibody expression through inducing immune dysfunction and chronic inflammation. Thus, more attention should be paid to the vaccination for high CVAI population to improve the effectiveness of vaccination, which could provide more robust support for COVID-19 epidemic prevention and control.

3.
Plant J ; 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39215633

RESUMEN

BARENTSZ (BTZ), a core component of the exon junction complex, regulates diverse developmental processes in animals. However, its evolutionary and developmental roles in plants remain elusive. Here, we revealed that three groups of paralogous BTZ genes existed in Poaceae, and Group 2 underwent loss-of-function mutations during evolution. They showed surprisingly low (~33%) sequence identities, implying functional divergence. Two genes retained in rice, OsBTZ1 and OsBTZ3, were edited; however, the resultant osbtz1 and osbtz3 mutants showed similar floral morphological and functional defects at a low frequency. When growing under low-temperature conditions, developmental abnormalities became pronounced, and new floral variations were induced. In particular, stamen and carpel functionality was impaired in these rice btz mutants. The double-gene mutant osbtz1/3 shared these floral defects with an increased frequency, which was further induced under low-temperature conditions. OsBTZs interacted with OsMADS7 and OsMADS8, and the floral expressions of the OsTGA10 and MADS-box genes were correlatively altered in these osbtz mutants and responded to low-temperature treatment. These novel findings demonstrate that two highly diverged OsBTZs are required to maintain floral developmental stability under low-temperature conditions, and play an integral role in male and female fertility, thus providing new insights into the indispensable roles of BTZ genes in plant development and adaptive evolution.

4.
Acad Radiol ; 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39183131

RESUMEN

RATIONALE AND OBJECTIVES: This study aims to explore the feasibility of the deep learning radiomics nomogram (DLRN) for predicting tumor status and axillary lymph node metastasis (ALNM) after neoadjuvant chemotherapy (NAC) in patients with breast cancer. Additionally, we employ a Cox regression model for survival analysis to validate the effectiveness of the fusion algorithm. MATERIALS AND METHODS: A total of 243 patients who underwent NAC were retrospectively included between October 2014 and July 2022. The DLRN integrated clinical characteristics as well as radiomics and deep transfer learning features extracted from ultrasound (US) images. The diagnostic performance of DLRN was evaluated by constructing ROC curves, and the clinical usefulness of models was assessed using decision curve analysis (DCA). A survival model was developed to validate the effectiveness of the fusion algorithm. RESULTS: In the training cohort, the DLRN yielded area under the receiver operating characteristic curve values of 0.984 and 0.985 for the tumor and LNM, while 0.892 and 0.870, respectively, in the test cohort. The consistency indices (C-index) of the nomogram were 0.761 and 0.731, respectively, in the training and test cohorts. The Kaplan-Meier survival curves showed that patients in the high-risk group had significantly poorer overall survival than patients in the low-risk group (P < 0.05). CONCLUSION: The US-based DLRN model could hold promise as clinical guidance for predicting the status of tumors and LNM after NAC in patients with breast cancer. This fusion model can also predict the prognosis of patients, which could help clinicians make better clinical decisions.

5.
ANZ J Surg ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39051445

RESUMEN

BACKGROUND: Isolated splenic abscesses are rare, but increasingly reported with newer organisms and changes in mechanisms involved. We conducted a comparative review of publications from 1900-1977, 1977-1986, 1987-1995, and 1996-2022. METHODS: A systematic search in Embase and PubMed resulted in 522 publications (1111 cases). Data was tabulated, analysed, and compared. RESULTS: Patient demographics and symptoms remain unchanged although more Asian patients were reported. Metastatic infections remain the main cause, but COVID-19-linked and iatrogenic causes post bariatric surgery and splenic artery embolization are increasingly reported. Aerobic organisms remain the commonest (68%), with a variety of exotic organisms reported. Splenectomy remains the definitive treatment, although antibiotics only and percutaneous aspiration/catheter-drainage are increasingly used with reasonable outcomes, with salvage splenectomy for therapeutic failures not having significantly higher mortality than upfront splenectomy. CONCLUSIONS: Isolated splenic abscesses continue to be uncommon, with diagnosis requiring a high degree of suspicion. Non-surgical options for treatment can sometimes be definitive.

6.
J Biopharm Stat ; : 1-13, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557292

RESUMEN

Multiregional clinical trials (MRCTs) have become a favored strategy for new drug development. The accurate evaluation of treatment effects across different regions is crucial for interpreting the results of MRCTs. Consistency between regional and overall results ensures the extrapolability of the overall conclusions to individual regions. While numerous statistical methods have been proposed for consistency assessment, a notable proportion necessitate a substantial escalation in sample size, particularly in scenarios involving more than four regions within MRCTs. This, paradoxically, undermines the fundamental intent of MRCTs. In addition, standardized statistical criteria for concluding consistency are yet to be established. In this paper, we develop further consistency assessment approaches in the framework of two multivariate likelihood ratio test-based methods, namely mLRTa and mLRTb, wherein consistency is cast as the alternative and null hypotheses. Notably, our exploration unveils that qualitative methods such as the funnel approach and PMDA methods are special instances of mLRTa. Furthermore, our work underscores that these three qualitative methodologies roughly share the same level of assurance probability (AP). Intriguingly, when the number of regions in an MRCT surpasses five, even when the overall sample size guarantees a power of 90% or more and the true treatment effects remain uniform across regions, the AP remains below the 70% mark. Drawing from our meticulous examination of operational attributes, we recommend mLRTa with positive treatment effects in all regions in the alternative hypothesis with significance level 0.5 or mLRTb with all regional treatment effects being equal in the null and significance level of 0.2.

7.
BMC Genomics ; 25(1): 354, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594645

RESUMEN

The homeodomain-leucine zipper (HD-Zip) gene family plays a pivotal role in plant development and stress responses. Nevertheless, a comprehensive characterization of the HD-Zip gene family in kiwifruit has been lacking. In this study, we have systematically identified 70 HD-Zip genes in the Actinidia chinensis (Ac) genome and 55 in the Actinidia eriantha (Ae) genome. These genes have been categorized into four subfamilies (HD-Zip I, II, III, and IV) through rigorous phylogenetic analysis. Analysis of synteny patterns and selection pressures has provided insights into how whole-genome duplication (WGD) or segmental may have contributed to the divergence in gene numbers between these two kiwifruit species, with duplicated gene pairs undergoing purifying selection. Furthermore, our study has unveiled tissue-specific expression patterns among kiwifruit HD-Zip genes, with some genes identified as key regulators of kiwifruit responses to bacterial canker disease and postharvest processes. These findings not only offer valuable insights into the evolutionary and functional characteristics of kiwifruit HD-Zips but also shed light on their potential roles in plant growth and development.


Asunto(s)
Actinidia , Proteínas de Homeodominio , Proteínas de Homeodominio/genética , Genoma de Planta , Filogenia , Actinidia/genética , Leucina Zippers/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Perfilación de la Expresión Génica
8.
Stat Med ; 43(10): 1883-1904, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38634277

RESUMEN

Biomarker stratified clinical trial designs are versatile tools to assess biomarker clinical utility and address its relationship with clinical endpoints. Due to imperfect assays and/or classification rules, biomarker status is prone to errors. To account for biomarker misclassification, we consider a two-stage stratified design for survival outcomes with an adjustment for misclassification in predictive biomarkers. Compared to continuous and/or binary outcomes, the test statistics for survival outcomes with an adjustment for biomarker misclassification is much more complicated and needs to take special care. We propose to use the information from the observed biomarker status strata to construct adjusted log-rank statistics for true biomarker status strata. These adjusted log-rank statistics are then used to develop sequential tests for the global (composite) hypothesis and component-wise hypothesis. We discuss the power analysis with the control of the type-I error rate by using the correlations between the adjusted log-rank statistics within and between the design stages. Our method is illustrated with examples of the recent successful development of immunotherapy in nonsmall-cell lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Biomarcadores/análisis , Proyectos de Investigación , Ensayos Clínicos como Asunto
9.
ACS Macro Lett ; 13(5): 489-494, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38607650

RESUMEN

Synchronously improving the photothermal conversion efficiency and photodynamic activity of organic small molecule photosensitizers is crucial for their further wide application in cancer treatment. Recently, the emerging A-D-A photosensitizer-based phototherapy systems have attracted great interest due to their plentiful inherent merits. Herein, we propose a design strategy for A-D-A photosensitizers with synchronously enhanced photothermal conversion and reactive oxygen species (ROS) generation efficiencies. Side chain programming is carried out to design three A-D-A photosensitizers (IDT-H, IDT-Br, IDT-I) containing hexyl, bromohexyl, and iodohexyl side chains, respectively. Theoretical calculations confirm that a bulky iodine atom could weaken the intermolecular π-π stacking and enhance spin-orbit coupling constants of IDT-I. These molecular mechanisms enable IDT-I nanoparticles (NPs) to exhibit 2.4-fold and 1.7-fold higher ROS generation efficiency than that of IDT-H NPs and IDT-Br NPs, respectively, as well as the highest photothermal conversion efficiency. Both the experimental results in vitro and in vivo verify that IDT-I NPs are perfectly qualified for the mission of photothermal and photodynamic synergistic therapy. Therefore, in this contribution, we provide a promising perspective for the design of A-D-A photosensitizers with simultaneously improved photothermal and photodynamic therapy ability.

10.
Plant Commun ; 5(6): 100856, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38431772

RESUMEN

Actinidia arguta, the most widely distributed Actinidia species and the second cultivated species in the genus, can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit, rapid softening, and excellent cold tolerance. Adaptive evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still unclear. Here, we generated a chromosome-scale genome assembly of an autotetraploid male A. arguta accession. The genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 pseudo-chromosomes. Resequencing and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups, Southern and Northern, which first diverged 12.9 million years ago. A. arguta underwent two prominent expansions and one demographic bottleneck from the mid-Pleistocene climate transition to the late Pleistocene. Population genomics studies using paleoclimate data enabled us to discern the evolution of the species' adaptation to different historical environments. Three genes (AaCEL1, AaPME1, and AaDOF1) related to flesh softening were identified by multi-omics analysis, and their ability to accelerate flesh softening was verified through transient expression assays. A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome (Chr3) or autosomal chromosomes showed biased expression during stamen or carpel development. This chromosome-level assembly of the autotetraploid A. arguta genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of A. arguta.


Asunto(s)
Actinidia , Genoma de Planta , Tetraploidía , Actinidia/genética , Evolución Molecular , Adaptación Fisiológica/genética , Evolución Biológica
11.
Pharm Stat ; 23(4): 570-584, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38317373

RESUMEN

In recently conducted phase III trials in a rare disease area, patients received monthly treatment at a high dose of the drug, which targets to lower a specific biomarker level, closely associated with the efficacy endpoint, to around 10% across patients. Although this high dose demonstrated strong efficacy, treatments were withheld due to the reports of serious adverse events. Dosing in these studies were later resumed at a reduced dosage which targets to lower the biomarker level to 15%-35% across patients. Two questions arose after this disruption. The first is whether the efficacy of this revised regimen as measured by the reduction in annualized event rate is adequate to support the continuation of the development and the second is whether the potential bias due to the loss of patients during this dosing gap process can be gauged. To address these questions, we built a prediction model that quantitatively characterizes biomarker vs. endpoint relationship and predicts efficacy at the 15%-35% range of the biomarker level using the available data from the original high dose. This model predicts favorable event rate in the target biomarker level and shows that the bias due to the loss of patients is limited. These results support the continued development of the revised regimen, however, given the limitation of the data available, this prediction is planned to be validated further when data under the revised regimen become available.


Asunto(s)
Biomarcadores , Ensayos Clínicos Fase III como Asunto , Modelos Estadísticos , Humanos , Ensayos Clínicos Fase III como Asunto/métodos , Relación Dosis-Respuesta a Droga , Resultado del Tratamiento
12.
Contemp Clin Trials ; 138: 107467, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38331382

RESUMEN

There are very rich publications devoted to group sequential design, adaptive design and trial monitoring for continuous, binary and time to event endpoints. Many authors also discuss fixed design, blinded sample size re-estimation design and group sequential design for studies with a negative binomial outcome. Nonetheless, literature is sparse in adaptive design for a trial with a negative binomial endpoint. The features of such an endpoint in a flexible trial design setting remains inadequately understood. In this research, we seek to bridge this knowledge gap by offering a thorough examination of utilizing data components from a two-stage adaptive design for unblinded conditional power calculation and corresponding sample size re-estimation. We also provide expression for calculating the probability of meeting the futility criterion to determine the appropriate timing for the interim analysis. To evaluate the performance of the design, we conduct simulations to assess its operation characteristics. Finally, we provide a helpful and illustrative example to demonstrate the practical applications of the methods.


Asunto(s)
Inutilidad Médica , Proyectos de Investigación , Humanos , Tamaño de la Muestra , Probabilidad
13.
Drug Des Devel Ther ; 18: 307-324, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38328440

RESUMEN

Aloe barbadensis Mill. has a long history of medicinal use in the annals of traditional Chinese medicine, wherein it has garnered considerable renown. Its multifaceted therapeutic properties, characterized by its anti-inflammatory and antibacterial attributes, alongside its established efficacy as a laxative agent, have been extensively documented. This review commences with an exploration of the nomenclature, fundamental characteristics, and principal constituents of Aloe barbadensis Mill. responsible for its laxative effects. Subsequently, we delve into an extensive examination of the molecular mechanisms underlying Aloe barbadensis Mill.'s laxative properties, types of constipation treatments, commercially available preparations, considerations pertaining to toxicity, and its clinical applications. This review aims to serve as a comprehensive reference point for healthcare professionals and researchers, fostering an enhanced understanding of the optimal utilization of Aloe barbadensis Mill. in the treatment of constipation.


Asunto(s)
Aloe , Extractos Vegetales , Humanos , Extractos Vegetales/uso terapéutico , Laxativos/uso terapéutico , Medicina Tradicional China , Estreñimiento/tratamiento farmacológico
14.
Mol Biotechnol ; 66(5): 991-999, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38270756

RESUMEN

Estrogen receptor (ER) is a molecular marker and target for diagnosing and treating breast cancer (BC). ER-α36, a novel estrogen receptor subtype, involved in the proliferation, differentiation, metastasis, and invasion of tumor cells. It is closely linked to the progression of various cancers. Therefore, studying ER is of high significance in treating BC. In this study, we will investigate the changes in the expression level of ER-α36 in patients with BC treated by chemotherapy through meta-analysis, so as to evaluate the clinical value of ER-α36 in the prognosis of BC treated by chemotherapy. English databases such as PubMed, Web of Science, Embase, and The Cochrane Library were searched to retrieve the articles published from the establishment of the database to April 2023. The keywords included chemotherapy, neoadjuvant chemotherapy, breast cancer, estrogen receptor alpha, and ER-α36. Five suitable studies, encompassing 636 patients, were ultimately selected. The meta-analysis results revealed that, following the chemotherapy, the analysis of ER-α36 positive cases yielded an Odds Ratio (OR) of 0.42, a 95% confidence interval (CI) of 0.28-0.64 (Z = 4.00, P < 0.0001). Additionally, the analysis of cases exhibiting remission in BC demonstrated an OR of 2.22 (95% CI = 1.40-3.50, Z = 3.40, P = 0.0007). Compared to patients receiving single chemotherapy agents or those untreated with chemotherapy, the combined use of multiple chemotherapy drugs can significantly reduce the levels of ER-α36 in BC patients, enhancing the remission rate of BC. ER-α36 can serve as a critical indicator for assessing the prognosis of BC following chemotherapy.


Asunto(s)
Neoplasias de la Mama , Receptor alfa de Estrógeno , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Receptor alfa de Estrógeno/metabolismo , Receptor alfa de Estrógeno/genética , Femenino , Pronóstico , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Antineoplásicos/uso terapéutico
15.
Hepatol Res ; 54(6): 588-599, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38241146

RESUMEN

BACKGROUND/PURPOSE: Patients with alcohol-associated cirrhosis and acute decompensation are considered critically ill and have a higher risk of short-term mortality. This study aimed to establish a nomogram to evaluate their 90-day survival and identify factors that affect disease progression. METHODS: We included patients from September 2008 to December 2016 (n = 387 in the derivation group) and from January 2017 to August 2020 (n = 157 in the validation group). LASSO regression and Cox multivariate risk regression were used to analyze the influencing factors of the 90-day mortality risk, and a nomogram was constructed. The performance of a model was analyzed based on the C-index, area under the receiver operating curve, calibration curve, and decision curve analysis. RESULTS: Total bilirubin >10 upper limit of normal, high-density lipoprotein cholesterol, lymphocyte and monocyte ratios ≤2.33, white blood cells, and hemoglobin were identified as independent risk factors affecting the 90-day mortality risk of patients and the nomogram was developed. A nomogram demonstrated excellent model predictive accuracy in both the derivation and validation cohorts (C-index: 0.976 and 0.945), which was better than other commonly used liver scoring models (p < 0.05). The nomogram also performed good calibration ability and more clinical net benefit. According to the nomogram score, patients were divided into high- and low-risk groups. Mortality was significantly higher in the high-risk group than in the low-risk group (p < 0.0001). CONCLUSION: The nomogram could accurately predict the 90-day mortality risk in patients with alcohol-associated cirrhosis and acute decompensation, helping to identify high-risk patients and personalize treatment at their first admission.

16.
Small ; 20(14): e2307664, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37972254

RESUMEN

Phototheranostics continues to flourish in cancer treatment. Due to the competitive relationships between these photophysical processes of fluorescence emission, photothermal conversion, and photodynamic action, it is critical to balance them through subtle photosensitizer designs. Herein, it is provided a useful guideline for constructing A-D-A photosensitizers with superior phototheranostics performance. Various cyanoacetate group-modified end groups containing ester side chains of different length are designed to construct a series of A-D-A photosensitizers (F8CA1 ∼ F8CA4) to study the structure-property relationships. It is surprising to find that the photophysical properties of A-D-A photosensitizers can be precisely regulated by these tiny structural changes. The results reveal that the increase in the steric hindrance of ester side chains has positive impacts on their photothermal conversion capabilities, but adverse impacts on the fluorescence emission and photodynamic activities. Notably, these tiny structural changes lead to their different aggregation behavior. The molecule mechanisms are detailedly explained by theoretical calculations. Finally, F8CA2 nanoparticles with more balanced photophysical properties perform well in fluorescence imaging-guided photothermal and type I&II photodynamic synergistic cancer therapy, even under hypoxic conditions. Therefore, this work provides a novel practicable construction strategy for desired A-D-A photosensitizers.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotosensibilizantes/química , Nanomedicina Teranóstica/métodos , Fotoquimioterapia/métodos , Fototerapia/métodos , Neoplasias/tratamiento farmacológico , Nanopartículas/química , Ésteres/uso terapéutico
17.
PLoS Comput Biol ; 19(9): e1011423, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37656743

RESUMEN

There are many contrasting results concerning the effectiveness of Test-Trace-Isolate (TTI) strategies in mitigating SARS-CoV-2 spread. To shed light on this debate, we developed a novel static-temporal multiplex network characterizing both the regular (static) and random (temporal) contact patterns of individuals and a SARS-CoV-2 transmission model calibrated with historical COVID-19 epidemiological data. We estimated that the TTI strategy alone could not control the disease spread: assuming R0 = 2.5, the infection attack rate would be reduced by 24.5%. Increased test capacity and improved contact trace efficiency only slightly improved the effectiveness of the TTI. We thus investigated the effectiveness of the TTI strategy when coupled with reactive social distancing policies. Limiting contacts on the temporal contact layer would be insufficient to control an epidemic and contacts on both layers would need to be limited simultaneously. For example, the infection attack rate would be reduced by 68.1% when the reactive distancing policy disconnects 30% and 50% of contacts on static and temporal layers, respectively. Our findings highlight that, to reduce the overall transmission, it is important to limit contacts regardless of their types in addition to identifying infected individuals through contact tracing, given the substantial proportion of asymptomatic and pre-symptomatic SARS-CoV-2 transmission.


Asunto(s)
COVID-19 , Epidemias , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Trazado de Contacto , Distanciamiento Físico
18.
ACS Appl Mater Interfaces ; 15(38): 45076-45082, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37721972

RESUMEN

Boltzmann distribution thermal tails of carriers restrain the subthreshold swing (SS) of field-effect transistors (FETs) to be lower than 60 mV/decade at room temperature, which restrains the reduction of operate-voltage and power consumption of transistors. The negative-capacitance FET (NC FET) is expected to break through this physical limit and obtain a steep SS by amplifying the gate voltage through the negative capacitance effect of the ferroelectric thin film, providing a new way to further reduce the power consumption of the transistor at the end of Moore's law. Here, we show a MoS2 NC FET with a CuInP2S6 ferroelectric, exhibiting a large on/off ratio of 108, a steep SS as low as 6 mV/decade, and a wide sub-60 mV/decade drain current range of more than 4 orders of magnitude while sacrificially inducing a huge hysteresis larger than 500 mV. Furthermore, we found that by inserting the h-phase boron nitride (h-BN) layer with suitable thickness, the dielectric capacitance matches the ferroelectric negative capacitance better, and thus the hysteresis on the transfer curve is reduced, and the ideal switching-behavior transistors with SS as low as 62 mV/decade and only 5 mV negligible hysteresis were obtained. Our work demonstrates that under the capacitance-matching condition, the hysteresis-free negative-capacitance transistors do not act as the predicted steep-slope transistors, but their voltage-saving still occurs instead as a type of effective transconductance booster with more than 20 times transconductance amplification.

19.
ACS Macro Lett ; 12(10): 1365-1371, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37737579

RESUMEN

Tumor-targeting phototheranostics has gradually developed as a powerful tool for the precise diagnosis and treatment of cancer. However, the designs of tumor-targeting phototheranostics agents with excellent multimodal phototherapy and fluorescence imaging (FLI) capability, as well as very few components, are still scarce and challenging for cancer treatment. Herein, a mitochondria-targeting multimodal phototheranostics system has been constructed by combining a designed amphiphilic pillararene WP5-2PEG-2TPP and the A-D-A fused-ring photosensitizer F8CA5. WP5-2PEG-2TPP is constructed by attaching the triphenylphosphonium cations to our previously reported dual PEG-functionalized amphiphilic pillararene, which can self-assemble into regular spherical nanocarriers with outstanding mitochondria targeting and water solubility. The A-D-A photosensitizer F8CA5 containing two methyl cyanoacetate group modified end groups displays superior photothermal conversion ability and dual type I/II photodynamic activity as well as strong NIR fluorescence emission. Through their strong union, multifunctional mitochondria-targeting phototheranostics agent F8CA5 NPs were obtained to be applied into FLI-guided synergistic photothermal and type I/II photodynamic therapy. As a result, F8CA5 NPs show good mitochondria-targeting and phototherapy effects in various tumor cells. Not only that, they can combat tumor hypoxia, which hinders the efficacy of photodynamic therapy. Therefore, this work provides a creative ideal for the construction of multifunctional tumor-targeting phototheranostic agents with excellent performance.

20.
Chembiochem ; 24(19): e202300461, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37463099

RESUMEN

BODIPY photosensitizers have been integrated with a hypoxia-activated prodrug to achieve synergistic photodynamic therapy (PDT) and chemotherapy. A novel BODIPY derivative BDP-CN was designed and synthesized. It had two cyano groups to make it complex well with a water-soluble pillar[5]arene. Their association constant was calculated to be (6.8±0.9)×106  M-1 . After self-assembly in water, regular spherical nanocarriers can be formed; these were used to encapsulate the hypoxia-activated prodrug tirapazamine (TPZ). BDP-CN displayed excellent photodynamic activity to complete PDT. In this process, O2 can be continuously consumed to activate TPZ to allow it to be converted to a benzotriazinyl (BTZ) radical with high cytotoxicity to complete chemotherapy. As a result, the formed nanoparticles showed excellent synergistic photodynamic therapy and chemotherapy efficacy. The synergistic therapy mechanism is discussed in detail.

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