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1.
Nature ; 615(7954): 813-816, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36991189

RESUMEN

The proton is one of the main building blocks of all visible matter in the Universe1. Among its intrinsic properties are its electric charge, mass and spin2. These properties emerge from the complex dynamics of its fundamental constituents-quarks and gluons-described by the theory of quantum chromodynamics3-5. The electric charge and spin of protons, which are shared among the quarks, have been investigated previously using electron scattering2. An example is the highly precise measurement of the electric charge radius of the proton6. By contrast, little is known about the inner mass density of the proton, which is dominated by the energy carried by gluons. Gluons are hard to access using electron scattering because they do not carry an electromagnetic charge. Here we investigated the gravitational density of gluons using a small colour dipole, through the threshold photoproduction of the J/ψ particle. We determined the gluonic gravitational form factors of the proton7,8 from our measurement. We used a variety of models9-11 and determined, in all cases, a mass radius that is notably smaller than the electric charge radius. In some, but not all cases, depending on the model, the determined radius agrees well with first-principle predictions from lattice quantum chromodynamics12. This work paves the way for a deeper understanding of the salient role of gluons in providing gravitational mass to visible matter.

2.
Nature ; 609(7925): 41-45, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36045235

RESUMEN

When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure1-3, and mapping out the strength and the isospin structure (neutron-proton (np) versus proton-proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3-5. Two-nucleon knockout or 'triple coincidence' reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6-8 have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon-nucleon interaction.

3.
Nature ; 611(7935): 265-270, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36261531

RESUMEN

The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities1 that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities2 map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades2. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.

4.
Nature ; 594(7861): 33-36, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34002091

RESUMEN

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

5.
Proc Natl Acad Sci U S A ; 121(23): e2322283121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38814873

RESUMEN

Single-atom catalysts (SACs) with atomic dispersion active sites have exhibited huge potentials in peroxymonosulfate (PMS)-based Fenton-like chemistry in water purification. However, four-N coordination metal (MN4) moieties often suffer from such problems as low selectivity and narrow workable pH. How to construct SACs in a controllable strategy with optimized electronic structures is of great challenge. Herein, an innovative strategy (i.e., the "4 + 1" fabrication) was devised to precisely modulate the first-shell coordinated microenvironment of FeN4 SAC using an additional N (SA-FeN5). This leads to almost 100% selective formation of high-valent iron-oxo [Fe(IV)═O] (steady-state concentration: 2.00 × 10-8 M) in the SA-FeN5/PMS system. In-depth theoretical calculations unveil that FeN5 configuration optimizes the electron distribution of monatomic Fe sites, which thus fosters PMS adsorption and reduces the energy barrier for Fe(IV)═O generation. SA-FeN5 was then attached to polyvinylidene difluoride membrane for a continuous flow device, showing long-term abatement of the microcontaminant. This work furnishes a general strategy for effective PMS activation and selective high-valent metal-oxo species generation by high N-coordination number regulation in SACs, which would provide guidance in the rational design of superior environmental catalysts for water purification.

6.
Plant Mol Biol ; 114(3): 53, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714550

RESUMEN

Plants have a variety of regulatory mechanisms to perceive, transduce, and respond to biotic and abiotic stress. One such mechanism is the calcium-sensing CBL-CIPK system responsible for the sensing of specific stressors, such as drought or pathogens. CBLs perceive and bind Calcium (Ca2+) in response to stress and then interact with CIPKs to form an activated complex. This leads to the phosphorylation of downstream targets, including transporters and ion channels, and modulates transcription factor levels and the consequent levels of stress-associated genes. This review describes the mechanisms underlying the response of the CBL-CIPK pathway to biotic and abiotic stresses, including regulating ion transport channels, coordinating plant hormone signal transduction, and pathways related to ROS signaling. Investigation of the function of the CBL-CIPK pathway is important for understanding plant stress tolerance and provides a promising avenue for molecular breeding.


Asunto(s)
Proteínas de Plantas , Transducción de Señal , Estrés Fisiológico , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Plantas/genética , Plantas/metabolismo , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Calcio/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
7.
Ann Surg Oncol ; 31(3): 1477-1487, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38082168

RESUMEN

BACKGROUND: We sought to determine the impact of historical redlining on travel patterns and utilization of high-volume hospitals (HVHs) among patients undergoing complex cancer operations. METHODS: The California Department of Health Care Access and Information database was utilized to identify patients who underwent esophagectomy (ES), pneumonectomy (PN), pancreatectomy (PA), or proctectomy (PR) for cancer between 2010 and 2020. Patient ZIP codes were assigned Home Owners' Loan Corporation grades (A: 'Best'; B: 'Still Desirable'; C: 'Definitely Declining'; and D: 'Hazardous/Redlined'). A clustered multivariable regression was used to assess the likelihood of patients undergoing surgery at an HVH, bypassing the nearest HVH, and total real driving time and travel distance. RESULTS: Among 14,944 patients undergoing high-risk cancer surgery (ES: 4.7%, n = 1216; PN: 57.8%, n = 8643; PD: 14.4%, n = 2154; PR: 23.1%, n = 3452), 782 (5.2%) individuals resided in the 'Best', whereas 3393 (22.7%) individuals resided in redlined areas. Median travel distance was 7.8 miles (interquartile range [IQR] 4.1-14.4) and travel time was 16.1 min (IQR 10.7-25.8). Overall, 10,763 (ES: 17.4%; PN: 76.0%; PA: 63.5%; PR: 78.4%) patients underwent surgery at an HVH. On multivariable regression, patients residing in redlined areas were less likely to undergo surgery at an HVH (odds ratio [OR] 0.67, 95% confidence interval [CI] 0.54-0.82) and were more likely to bypass the nearest hospital (OR 1.80, 95% CI 1.44-2.46). Notably, Medicaid insurance, minority status, limited English-language proficiency, and educational level mediated the disparities in access to HVH. CONCLUSION: Surgical disparities in access to HVH among patients from historically redlined areas are largely mediated by social determinants such as insurance and minority status.


Asunto(s)
Hospitales de Alto Volumen , Neoplasias , Estados Unidos , Humanos , Accesibilidad a los Servicios de Salud , California , Grupos Minoritarios
8.
Ann Surg Oncol ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38872045

RESUMEN

PURPOSE: This study was designed to characterize features of rapid relapse TNBC (rrTNBC), an aggressive, poor prognosis breast cancer subset using the National Cancer Database (NCDB). METHODS: Patients diagnosed with TNBC between 2010 and 2019 within NCDB were included in analyses. rrTNBC was defined as all-cause mortality ≤24 months from diagnosis. Patient demographic, tumor, and treatment association with rrTNBC were evaluated in univariate, bivariate analyses, and multiple logistic regression models. Two-part models are used to compare receipt of treatment (i.e., receipt of both chemotherapy and breast surgery) versus not in its relationship with rrTNBC. RESULTS: Overall, 14.5% of patients were categorized as rrTNBC. Age older than 75 years (-41.3%), Black race (-1.4%), Medicare (-2.6%), and Charlson-Deyo score ≥2 (-4.9%) were associated with a lower probability of receiving both chemotherapy and breast surgery. Not receiving both treatments (vs. receiving both chemotherapy and breast surgery) was associated with a two-to-three-fold higher probability of rrTNBC among patients aged older than 75 years (16.6% vs. 6%), having Medicare (3.6% vs. 1.6%), and Charlson-Deyo score ≥2 (16.6% vs. 5.9%). CONCLUSIONS: Age, insurance, and comorbidity were related to a lower likelihood of treatment; yet receiving treatment reduced the risk of rrTNBC threefold for each. These findings might be valuable to inform clinical care delivery, as well as future research that examines treatment protocols among diverse patients.

9.
Ann Surg Oncol ; 31(1): 365-375, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37865937

RESUMEN

BACKGROUND: The objective of this study was to examine the association between racialized economic segregation, allostatic load (AL), and all-cause mortality in patients with breast cancer. PATIENTS AND METHODS: Women aged 18+ years with stage I-III breast cancer diagnosed between 01/01/2012 and 31/12/2020 were identified in the Ohio State University cancer registry. Racialized economic segregation was measured at the census tract level using the index of concentration at the extremes (ICE). AL was calculated with biomarkers from the cardiac, metabolic, immune, and renal systems. High AL was defined as AL greater than the median. Univariable and multivariable regression analyses using restricted cubic splines examined the association between racialized economic segregation, AL, and all-cause mortality. RESULTS: Among 4296 patients, patients residing in neighborhoods with the highest racialized economic segregation (Q1 versus Q4) were more likely to be Black (25% versus 2.1%, p < 0.001) and have triple-negative breast cancer (18.2% versus 11.6%, p < 0.001). High versus low racialized economic segregation was associated with high AL [adjusted odds ratio (aOR) 1.40, 95% confidence interval (CI) 1.21-1.61] and worse all-cause mortality [adjusted hazard ratio (aHR) 1.41, 95% CI 1.08-1.83]. In dose-response analyses, patients in lower segregated neighborhoods (relative to the 95th percentile) had lower odds of high AL, whereas patients in more segregated neighborhoods had a non-linear increase in the odds of high AL. DISCUSSION: Racialized economic segregation is associated with high AL and a greater risk of all-cause mortality in patients with breast cancer. Additional studies are needed to elucidate the causal pathways and mechanisms linking AL, neighborhood factors, and patient outcomes.


Asunto(s)
Alostasis , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Características de la Residencia , Modelos de Riesgos Proporcionales , Sistema de Registros
10.
NMR Biomed ; 37(7): e5084, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38104563

RESUMEN

In recent years, low-frequency oscillations (LFOs) (0.01-0.1 Hz) have been a subject of interest in resting-state functional magnetic resonance imaging research. They are believed to have many possible driving mechanisms, from both regional and global sources. Internal fluctuations in the partial pressure of CO2 (PCO2) has long been thought of as one of these major driving forces, but its exact contributions compared with other mechanisms have yet to be fully understood. This study examined the effects of end-tidal PCO2 (PetCO2) oscillations on LF cerebral hemodynamics and cerebrospinal fluid (CSF) dynamics under "clamped PetCO2" and "free-breathing" conditions. Under clamped PetCO2, a participant's PetCO2 levels were fixed to their baseline average, whereas PetCO2 was not controlled in free breathing. Under clamped PetCO2, the fractional amplitude of hemodynamic LFOs in the occipital and sensorimotor cortex and temporal lobes were found to be significantly reduced. Additionally, the fractional amplitude of CSF LFOs, measured at the fourth ventricle, was found to be reduced by almost one-half. However, the spatiotemporal distributions of blood and CSF delay times, as measured by cross-correlation in the LF domain, were not significantly altered between conditions. This study demonstrates that, while PCO2 oscillations significantly mediate LFOs, especially those observed in the CSF, other mechanisms are able to maintain LFOs, with high correlation, even in their absence.


Asunto(s)
Dióxido de Carbono , Humanos , Dióxido de Carbono/metabolismo , Masculino , Adulto , Imagen por Resonancia Magnética , Femenino , Circulación Cerebrovascular/fisiología , Volumen de Ventilación Pulmonar/fisiología , Hemodinámica , Adulto Joven , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo
11.
Phys Rev Lett ; 132(14): 143601, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640368

RESUMEN

Uninhibited control of the complex spatiotemporal quantum wave function of a single photon has so far remained elusive even though it can dramatically increase the encoding flexibility and thus the information capacity of a photonic quantum link. By fusing temporal waveform generation in an atomic ensemble and spatial single-photon shaping, we hereby demonstrate for the first time complete spatiotemporal control of a propagation invariant (2+1)D Airy single-photon optical bullet. These correlated photons are not only self-accelerating and impervious to spreading as their classical counterparts, but can be concealed and revealed in the presence of strong classical stray light.

12.
Phys Rev Lett ; 132(9): 099901, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38489658

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.123.107703.

13.
Phys Rev Lett ; 132(16): 162501, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38701469

RESUMEN

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6

14.
Langmuir ; 40(12): 6402-6412, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38489303

RESUMEN

A theoretical model was developed to describe the dynamics of a deformable fluid interface interacting with an approaching solid without contact by both the attractive electrostatic and van der Waals (i.e., vdW) interaction, analogous to the situation in the experiments by electric force microscopy (i.e., EFM) or electric-surface force apparatus (i.e., E-SFA) involved in the soft fluid interface. On the basis of this model, a numerical study of the deformation of the fluid interface, the force-vs-separation behavior, and the critical limiting conditions of contact has systematically been carried out. Our results show that the surface pressure induced by the electrostatic interaction plays a more prominent role in the deformation of the fluid interface than the vdW interaction does, and there exists a principal length scale associated with the relative strength of the electrostatic field to the surface tension, affecting the fluid interface shape under the electrostatic field. It was also shown that both the force-distance curves and the corresponding curves of fluid interface deformation peak versus distance for various electrostatic fields satisfy the universal scaling power law. Moreover, an analytical solution to the Euler-Lagrange differential equation governing the deformation of the fluid interface under the external electric field is obtained, and two extended formulas for explicitly describing the principal length scales that respectively characterize the lateral and longitudinal deformations of the fluid interface were determined.

15.
J Surg Oncol ; 129(7): 1179-1186, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38643486

RESUMEN

BACKGROUND AND OBJECTIVES: Given persistent racial disparities in breast cancer outcomes, this study explores racial differences in disease-specific mortality and surgical management among patients with microinvasive ductal carcinoma in situ (DCIS-MI). METHODS: The Surveillance, Epidemiology, and End Results Program was queried for patients aged 18+ years with DCIS-MI between January 1, 2010 and December 31, 2018. The study cohort was divided into non-Hispanic Black (NHB) and non-Hispanic White (NHW) patients. Disease-specific mortality was evaluated using Cox proportional hazards models. RESULTS: A total of 3400 patients were identified, of which 569 (16.7%) were NHB and 2831 (83.3%) were NHW. Compared with NHW patients, NHB patients had more positive lymph nodes (7.6% vs. 3.9% p < 0.001). In addition, NHB women were more likely to undergo axillary lymph node dissection (6.0% vs. 3.8%, p = 0.044) and receive chemotherapy (11.8% vs. 7.2%, p < 0.001). There were no racial differences in breast surgery type (p = 0.168), reconstructive surgery (p = 0.362), or radiation therapy (p = 0.342). Overall, NHB patients had worse disease-specific mortality (adjusted hazard ratio 2.13, 95% confidence interval [CI]: 1.10-4.14) with mortality risks diverging from NHW women after 3 years (6 years rate ratio [RR] 2.12, 95% CI: 1.13-4.34; 9 years RR 2.32, 95% CI: 1.24-4.35). CONCLUSIONS: NHB women with DCIS-MI present with higher nodal disease burden and experience worse disease-specific mortality than NHW women.


Asunto(s)
Neoplasias de la Mama , Carcinoma Intraductal no Infiltrante , Disparidades en Atención de Salud , Programa de VERF , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Negro o Afroamericano/estadística & datos numéricos , Neoplasias de la Mama/etnología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Carcinoma Intraductal no Infiltrante/etnología , Carcinoma Intraductal no Infiltrante/mortalidad , Carcinoma Intraductal no Infiltrante/cirugía , Estudios de Seguimiento , Mastectomía/mortalidad , Invasividad Neoplásica , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Blanco/estadística & datos numéricos
16.
Environ Sci Technol ; 58(5): 2271-2281, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38270974

RESUMEN

To mitigate methane emission from urban natural gas distribution systems, it is crucial to understand local leak rates and occurrence rates. To explore urban methane emissions in cities outside the U.S., where significant emissions were found previously, mobile measurements were performed in 12 cities across eight countries. The surveyed cities range from medium size, like Groningen, NL, to large size, like Toronto, CA, and London, UK. Furthermore, this survey spanned across European regions from Barcelona, ES, to Bucharest, RO. The joint analysis of all data allows us to focus on general emission behavior for cities with different infrastructure and environmental conditions. We find that all cities have a spectrum of small, medium, and large methane sources in their domain. The emission rates found follow a heavy-tailed distribution, and the top 10% of emitters account for 60-80% of total emissions, which implies that strategic repair planning could help reduce emissions quickly. Furthermore, we compare our findings with inventory estimates for urban natural gas-related methane emissions from this sector in Europe. While cities with larger reported emissions were found to generally also have larger observed emissions, we find clear discrepancies between observation-based and inventory-based emission estimates for our 12 cities.


Asunto(s)
Contaminantes Atmosféricos , Gas Natural , Ciudades , Gas Natural/análisis , Metano/análisis , Contaminantes Atmosféricos/análisis , Londres
17.
Curr Oncol Rep ; 26(1): 10-20, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38100011

RESUMEN

PURPOSE OF REVIEW: Update on current racial disparities in the detection and treatment of breast cancer. RECENT FINDINGS: Breast cancer remains the leading cause of cancer death among Black and Hispanic women. Mammography rates among Black and Hispanic women have surpassed those among White women, with studies now advocating for earlier initiation of breast cancer screening in Black women. Black, Hispanic, Asian, and American Indian and Alaskan Native women continue to experience delays in diagnosis and time to treatment. Further, racial discrepancies in receipt of guideline-concordant care, access to genetic testing and surgical reconstruction persist. Disparities in the initiation, completion, toxicity, and efficacy of chemotherapy, endocrine therapy, and targeted drug therapy remain for racially marginalized women. Efforts to evaluate the impact of race and ethnicity across the breast cancer spectrum are increasing, but knowledge gaps remain and further research is necessary to reduce the disparity gap.


Asunto(s)
Neoplasias de la Mama , Disparidades en Atención de Salud , Femenino , Humanos , Negro o Afroamericano , Neoplasias de la Mama/terapia , Neoplasias de la Mama/cirugía , Etnicidad , Blanco
18.
Clin Radiol ; 79(3): 205-212, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38218705

RESUMEN

AIM: To explore the utility of the 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) in the differential diagnosis of IgG4-related lymphadenopathy (IgG4-RLAD) and angioimmunoblastic T-cell lymphoma (AITL). MATERIALS AND METHODS: Retrospective analysis of 18F-FDG PET/CT imaging findings in clinically diagnosed IgG4-RLAD and AITL cases was undertaken to record the distribution, morphological characteristics, and imaging features of the affected lymph nodes, as well as FDG uptake of the spleen and bone marrow. Standardised uptake values normalised to lean body mass were evaluated for maximum (SULmax), average (SULavg), and peak values (SULpeak). Univariate and multivariate logistic regression was used to screen for statistically significant imaging findings to discriminate IgG4-RLAD from AITL. RESULTS: Twenty-two cases of IgG4-RLAD (17 men, five women, median age 49.5 years) and 22 cases of AITL (16 men, six women, median age 55 years) were finally included in the analysis. There were no AITL patients with involvement of a single lymph node region. AITL patients had more involvement of the different nodal regions except cervical and pelvic nodal regions. A practical assessment method based on a combination of SULpeak-LN/SULavg-liver, SULpeak-spleen, and the number of involved nodal regions, improved the performance for differential diagnosis between both groups with an overall classification accuracy of 90.9%. CONCLUSIONS: 18F-FDG PET/CT is a useful tool for distinguishing AITL from IgG4-RLAD, and it can also help determine the optimal biopsy site for suspected cases of IgG4-RLAD or AITL, reduce the need for re-biopsy procedures, and enable physicians to develop timely treatment strategies.


Asunto(s)
Linfadenopatía , Linfoma de Células T , Masculino , Humanos , Femenino , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Estudios Retrospectivos , Diagnóstico Diferencial , Inmunoglobulina G , Linfadenopatía/diagnóstico por imagen , Linfoma de Células T/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Radiofármacos
19.
Clin Radiol ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38797608

RESUMEN

AIM: We aimed to compare the diagnostic performance of transvaginal sonography (TVS) versus magnetic resonance imaging (MRI) in identifying deep infiltrating endometriosis (DIE) in the rectovaginal septum (RVS) of affected patients. MATERIALS AND METHODS: An extensive search was conducted in the PubMed, Embase databases to identify available publications up to November 2023. Studies evaluating the diagnostic perfor-mance of TVS and MRI for DIE in patients with rectovaginal septum involvement were all included. Sensitivity and specificity analyses employed the DerSi-monian and Laird method, complemented by the Freeman-Tukey double arc-sine trans-formation. Additionally, the study quality was rigorously evaluated using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) method. RESULTS: The meta-analysis encompassed 8 articles with a total of 721 patients. It revealed that the overall sensitivity of TVS was 0.51 (95% CI: 0.31-0.72), contrasted with 0.74 (95% CI: 0.66-0.82) for MRI. This finding suggests a higher sensitivity of MRI compared to TVS (P=0.04). Conversely, the overall specificity was 0.97 (95%CI: 0.94-1.00) for TVS and 0.93 (95% CI: 0.84-0.99) for MRI, indicating a comparable level of specificity between the two modalities (P=0.22). CONCLUSION: Our meta-analysis reveals that MRI exhibits higher sensitivity and comparable specificity to TVS in patients with DIE of the RVS. However, the limited number of articles included may affect the evidence of these results. Therefore, further d number of articles included may affect the evidence of these results. Therefore, further research with larger sample sizes and prospective designs is essential to validate these findings.

20.
Clin Radiol ; 79(2): e273-e281, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38065776

RESUMEN

AIM: To explore the value of multimodal magnetic resonance imaging (MRI) radiomics combined with traditional radiologist-defined semantic characteristics and conventional (cMRI) and functional MRI (fMRI) texture features in predicting Fuhrman grade of clear cell renal cell carcinoma (ccRCC). MATERIALS AND METHODS: The data of 89 patients with histopathologically proven ccRCC (low-grade, 54; high-grade, 35) were collected. Texture features were extracted from cMRI (T1- and T2-weighted imaging) and fMRI (Dixon-MRI; blood-oxygen-level dependent [BOLD]-MRI; and susceptibility-weighted imaging [SWI]) images, and the traditional characteristics (TC) were evaluated. Logistic regression analysis was performed to develop models based on TC, cMRI, and fMRI texture features for grading. Receiver operating characteristic (ROC) curve analysis and leave-group-out cross-validation (LGOCV) were performed to test the reliability of combined models. RESULTS: Two T2-weighted imaging-based, two Dixon_W-based, one Dixon_F-based, one BOLD-based, and three SWI-based texture features, and three TC were extracted for feature selection. TC, cMRI, fMRI, cMRI+fMRI, cMRI+TC, fMRI+TC, and cMRI+fMRI+TC models were constructed. The AUC of the cMRI+fMRI+TC model for differentiating high- from low-grade ccRCC was 0.74, with 81.42% accuracy, 75.93% sensitivity, and 91.43% specificity. The fMRI+TC model exhibited a performance similar to that of the cMRI+fMRI+TC model (p>0.05). The areas under the curve (AUCs) of the fMRI+TC and cMRI+fMRI+TC models were significantly higher than those of the other five models (all p<0.05). For the cMRI+fMRI+TC model, the mean accuracy was 85.40% after 100 LGOCV for the test sets. CONCLUSION: Multimodal MRI radiomics combined with TC, cMRI, and fMRI texture features may be a reliable quantitative approach for differentiating high-grade ccRCC from low-grade ccRCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/patología , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/patología , Estudios Retrospectivos , Reproducibilidad de los Resultados , Radiómica , Clasificación del Tumor , Imagen por Resonancia Magnética/métodos , Curva ROC
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