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1.
J Am Chem Soc ; 146(26): 17618-17623, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38899905

RESUMO

Upconversion (UC) of incoherent near-infrared (NIR) photons to visible photons through sensitized triplet-triplet annihilation (TTA) shows great potential in solar energy harvesting, photocatalysis, and bioimaging. However, the efficiencies of NIR-to-visible TTA-UC systems lag considerably behind those of their visible-to-visible counterparts. Here, we report a novel NIR-to-yellow TTA-UC system with a record quantum yield (QY) of 21.1% (out of a 100% maximum) and a threshold intensity of 20.2 W/cm2 by using InAs-based colloidal quantum dots (QDs) as triplet photosensitizers. The key to success is the epitaxial growth of an ultrathin ZnSe shell on InAs QDs that passivates the surface defects without impeding triplet energy transfer (TET) from QDs to surface-bound tetracene. Transient absorption spectroscopy verifies efficient TET efficiency of more than 80%, along with sufficiently long triplet lifetime of tetracene molecules, leading to high-performance UC. Moreover, high UC QYs (>18%) remain when larger InAs-based QDs─of which the absorption peak is red-shifted by more than 50 nm─are used as sensitizers, indicating the great potential of InAs QDs to utilize NIR photons with lower energy.

2.
Radiology ; 310(3): e232605, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38530176

RESUMO

Background Detection of extranodal extension (ENE) at pathology is a poor prognostic indicator for rectal cancer, but whether ENE can be identified at pretreatment MRI is, to the knowledge of the authors, unknown. Purpose To evaluate the performance of pretreatment MRI in detecting ENE using a matched pathologic reference standard and to assess its prognostic value in patients with rectal cancer. Materials and Methods This single-center study included a prospective development data set consisting of participants with rectal adenocarcinoma who underwent pretreatment MRI and radical surgery (December 2021 to January 2023). MRI characteristics were identified by their association with ENE-positive nodes (χ2 test and multivariable logistic regression) and the performance of these MRI features was assessed (area under the receiver operating characteristic curve [AUC]). Interobserver agreement was assessed by Cohen κ coefficient. The prognostic value of ENE detected with MRI for predicting 3-year disease-free survival was assessed by Cox regression analysis in a retrospective independent validation cohort of patients with locally advanced rectal cancer (December 2019 to July 2020). Results The development data set included 147 participants (mean age, 62 years ± 11 [SD]; 87 male participants). The retrospective cohort included 110 patients (mean age, 60 years ± 9; 79 male participants). Presence of vessel interruption and fusion (both P < .001), heterogeneous internal structure, and the broken-ring and tail signs (odds ratio range, 4.10-23.20; P value range, <.001 to .002) were predictors of ENE at MRI, and together achieved an AUC of 0.91 (95% CI: 0.88, 0.93) in detecting ENE. Interobserver agreement was moderate for the presence of vessel interruption and fusion (κ = 0.46 for both) and substantial for others (κ = 0.61-0.67). The presence of ENE at pretreatment MRI was independently associated with worse 3-year disease-free survival (hazard ratio, 3.00; P = .02). Conclusion ENE can be detected at pretreatment MRI, and its presence was associated with worse prognosis for patients with rectal cancer. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Eberhardt in this issue.


Assuntos
Segunda Neoplasia Primária , Neoplasias Retais , Humanos , Masculino , Pessoa de Meia-Idade , Extensão Extranodal , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias Retais/diagnóstico por imagem , Imageamento por Ressonância Magnética
3.
Sleep Breath ; 27(1): 91-101, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35416613

RESUMO

STUDY OBJECTIVES: Frailty is frequently reported following sleep disorders; however, the extent to which sleep disorders influence frailty remains unclear. In the current study, we performed a meta-analysis to evaluate the quantitative effects of different sleep disorders on frailty in the elderly. METHODS: We conducted a systematic search of several databases, including PubMed, Web of Science, Embase, and Scopus, to retrieve articles published from May 2009 to June 2021. The data outcomes are expressed as the odds ratio (OR) and 95% confidence interval (CI). RESULTS: Eighteen studies were included, with 39669 participants. Older adults with sleep disorders were found to have a higher risk of frailty (pooled OR = 1.49, 95%CI = 1.35-1.64, p < 0.01). Specifically, daytime sleepiness (pooled OR = 1.69, 95%CI = 1.09-2.61, p < 0.01), short sleep duration (pooled OR = 1.36, 95%CI = 1.20-1.54, p = 0.45), long sleep duration (pooled OR = 1.99, 95%CI = 1.39-2.85, p = 0.02), sleep latency extension (pooled OR = 1.38, 95%CI = 1.19-1.60, p = 0.72), and sleep disordered breathing (pooled OR = 1.30, 95%CI = 1.11-1.53, p = 0.37) were correlated with frailty. CONCLUSIONS: The risk of frailty differs between older adults with sleep disorders and controls, suggesting that the relationships between different sleep disorders and frailty vary. These results highlight the need to monitor sleep disorders of the elderly and conduct intervention to prevent or delay the frailty process.


Assuntos
Fragilidade , Síndromes da Apneia do Sono , Transtornos do Sono-Vigília , Idoso , Humanos , Razão de Chances , Sono , Transtornos do Sono-Vigília/epidemiologia
4.
Clin Infect Dis ; 74(4): 734-742, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34302458

RESUMO

Recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants may pose a threat to immunity. A systematic landscape of neutralizing antibodies against emerging variants is needed. We systematically searched for studies that evaluated neutralizing antibody titers induced by previous infection or vaccination against SARS-CoV-2 variants and collected individual data. We identified 106 studies meeting the eligibility criteria. Lineage B.1.351 (beta), P.1 (gamma) and B.1.617.2 (delta) significantly escaped natural infection-mediated neutralization, with an average of 4.1-fold (95% confidence interval [CI]: 3.6-4.7-fold), 1.8-fold (1.4-2.4-fold), and 3.2-fold (2.4-4.1-fold) reduction in live virus neutralization assay, while neutralizing titers against B.1.1.7 (alpha) decreased slightly (1.4-fold [95% CI: 1.2-1.6-fold]). Serum from vaccinees also led to significant reductions in neutralization of B.1.351 across different platforms, with an average of 7.1-fold (95% CI: 5.5-9.0-fold) for nonreplicating vector platform, 4.1-fold (3.7-4.4-fold) for messenger RNA platform, and 2.5-fold (1.7-2.9-fold) for protein subunit platform. Neutralizing antibody levels induced by messenger RNA vaccines against SARS-CoV-2 variants were similar to, or higher, than that derived from naturally infected individuals.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , COVID-19 , SARS-CoV-2 , COVID-19/imunologia , COVID-19/prevenção & controle , Humanos , Glicoproteína da Espícula de Coronavírus/genética , Vacinação
5.
Radiology ; 305(2): 364-372, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35852424

RESUMO

Background Accurate restaging of rectal cancer is crucial in the selection of candidates for local excision after neoadjuvant chemotherapy and radiation therapy (NCRT). The conventional approach of combined T2-weighted imaging and diffusion-weighted imaging (DWI) at MRI has been found to have limitations in restaging. Purpose To determine the diagnostic performance of contrast-enhanced MRI in distinguishing between pathologic stage ypT0-1 and ypT2-4 rectal cancer after NCRT compared with T2-weighted imaging and DWI by using surgical pathologic specimens as the reference standard. Materials and Methods This retrospective study evaluated MRI scans in all consecutive patients with locally advanced rectal cancer who underwent total mesorectal excision after NCRT in Peking University Cancer Hospital (Beijing, China) from January 2014 to October 2018. All MRI features obtained before and after NCRT were evaluated by two experienced radiologists, independently and blinded to personal, clinical, and histopathologic information. The post-NCRT yT stage was assigned based on high b value (b = 1000 sec/mm2) DWI with T2-weighted imaging (protocol 1) in the first round and on contrast-enhanced MRI scans (protocol 2) in a second round. The diagnostic accuracies for the differentiation of pathologic stage ypT0-1 from ypT2-4 tumors with the two protocols were compared. Multivariable regression analysis was used to explore the independent predictors of pathologic stage ypT0-1 tumors. Results A total of 328 patients (mean age, 57 years ± 10 [SD]; 227 men; 69%) were enrolled. The area under the receiver operating characteristic curve of the contrast-enhanced MRI protocol in predicting pathologic stage ypT0-1 tumors was 0.81 (95% CI: 0.77, 0.85), which was better than that of the T2-weighted DWI protocol (0.66; 95% CI: 0.60, 0.71; P < .001). Multivariable logistic regression analysis showed that yT stage after NCRT on contrast-enhanced MRI scans was the only independent predictor of pathologic stage ypT0-1 tumors (P < .001). Conclusion Contrast-enhanced MRI provides accurate differentiation of ypT0-1 from ypT2-4 tumors after neoadjuvant chemotherapy and radiation therapy. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Zins and Santiago in this issue.


Assuntos
Segunda Neoplasia Primária , Neoplasias Retais , Masculino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Quimiorradioterapia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Imageamento por Ressonância Magnética/métodos
6.
BMC Med ; 20(1): 36, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35086547

RESUMO

BACKGROUND: Evidence on vaccine-specific protection over time, in particular against the Delta variant, and protection afforded by a homologous third dose is urgently needed. METHODS: We used a previously published model and neutralization data for five vaccines-mRNA-1273, BNT162b2, NVX-CoV2373, V01, and CoronaVac- to evaluate long-term neutralizing antibody dynamics and predict time-varying efficacy against the Delta variant by specific vaccine, age group, and clinical severity. RESULTS: We found that homologous third-dose vaccination produces higher neutralization titers compared with titers observed following primary-series vaccination for all vaccines studied. We estimate the efficacy of mRNA-1273 and BNT162b2 against Delta variant infection to be 63.5% (95% CI: 51.4-67.3%) and 78.4% (95% CI: 72.2-83.5%), respectively, 14-30 days after the second dose, and that efficacy decreases to 36.0% (95% CI: 24.1-58.0%) and 38.5% (95% CI: 28.7-49.1%) 6-8 months later. Fourteen to 30 days after administration of homologous third doses, efficacy against the Delta variant would be 97.0% (95% CI: 96.4-98.5%) and 97.2% (95.7-98.1%). All five vaccines are predicted to provide good protection against severe illness from the Delta variant after both primary and homologous third dose vaccination. CONCLUSIONS: Timely administration of third doses of SARS-CoV-2-prototype-based vaccines can provide protection against the Delta variant, with better performance from mRNA vaccines than from protein and inactivated vaccines. Irrespective of vaccine technology, a homologous third dose for all types of vaccines included in the study will effectively prevent symptomatic and severe COVID-19 caused by the Delta variant. Long-term monitoring and surveillance of antibody dynamics and vaccine protection, as well as further validation of neutralizing antibody levels or other markers that can serve as correlates of protection against SARS-CoV-2 and its variants, are needed to inform COVID-19 pandemic responses.


Assuntos
COVID-19 , SARS-CoV-2 , Vacina de mRNA-1273 contra 2019-nCoV , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , Vacinas contra COVID-19 , Humanos , Cinética , Pandemias , Vacinas de mRNA
7.
BMC Med ; 20(1): 130, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35369871

RESUMO

BACKGROUND: Hundreds of millions of doses of coronavirus disease 2019 (COVID-19) vaccines have been administered globally, but progress on vaccination varies considerably between countries. We aimed to provide an overall picture of COVID-19 vaccination campaigns, including policy, coverage, and demand of COVID-19 vaccines. METHODS: We conducted a descriptive study of vaccination policy and doses administered data obtained from multiple public sources as of 8 February 2022. We used these data to develop coverage indicators and explore associations of vaccine coverage with socioeconomic and healthcare-related factors. We estimated vaccine demand as numbers of doses required to complete vaccination of countries' target populations according to their national immunization program policies. RESULTS: Messenger RNA and adenovirus vectored vaccines were the most commonly used COVID-19 vaccines in high-income countries, while adenovirus vectored vaccines were the most widely used vaccines worldwide (180 countries). One hundred ninety-two countries have authorized vaccines for the general public, with 40.1% (77/192) targeting individuals over 12 years and 32.3% (62/192) targeting those ≥ 5 years. Forty-eight and 151 countries have started additional-dose and booster-dose vaccination programs, respectively. Globally, there have been 162.1 doses administered per 100 individuals in target populations, with marked inter-region and inter-country heterogeneity. Completed vaccination series coverage ranged from 0.1% to more than 95.0% of country target populations, and numbers of doses administered per 100 individuals in target populations ranged from 0.2 to 308.6. Doses administered per 100 individuals in whole populations correlated with healthcare access and quality index (R2 = 0.59), socio-demographic index (R2 = 0.52), and gross domestic product per capita (R2 = 0.61). At least 6.4 billion doses will be required to complete interim vaccination programs-3.3 billion for primary immunization and 3.1 billion for additional/booster programs. Globally, 0.53 and 0.74 doses per individual in target populations are needed for primary immunization and additional/booster dose programs, respectively. CONCLUSIONS: There is wide country-level disparity and inequity in COVID-19 vaccines rollout, suggesting large gaps in immunity, especially in low-income countries.


Assuntos
Vacinas contra COVID-19 , COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Programas de Imunização , Políticas , Cobertura Vacinal
8.
Dis Colon Rectum ; 65(3): 322-332, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34459446

RESUMO

BACKGROUND: The cT3 substage criteria based on extramural depth of tumor invasion in rectal cancer have several limitations. OBJECTIVE: This study proposed that the distance between the deepest tumor invasion and mesorectal fascia on pretherapy MRI can distinguish the prognosis of patients with cT3 rectal cancer. DESIGN: This is a cohort study. SETTING: This study included a prospective, single-center, observational cohort and a retrospective, multicenter, independent validation cohort. PATIENT: Patients who had cT3 rectal cancer with negative mesorectal fascia undergoing neoadjuvant chemoradiotherapy followed by radical surgery were included in 4 centers in China from January 2013 to September 2014. INTERVENTION: Baseline MRI with the distance between the deepest tumor invasion and mesorectal fascia, extramural depth of tumor invasion, and mesorectum thickness were measured. MAIN OUTCOME MEASURES: The cutoff of the distance between the deepest tumor invasion and mesorectal fascia was determined by time-dependent receiver operating characteristic curves, supported by a 5-year progression rate from the prospective cohort, and was then validated in a retrospective cohort. RESULTS: There were 124 and 274 patients included in the prospective and independent validation cohorts. The distance between the deepest tumor invasion and mesorectal fascia was the only predictor for cancer-specific death (HR, 0.1; 95% CI, 0.0-0.7) and was also a significant predictor for distant recurrence (HR, 0.4; 95% CI, 0.2-0.9). No statistically significant difference was observed in prognosis between patients classified as T3a/b and T3c/d. LIMITATIONS: The sample size is relatively small, and the study focused on cT3 rectal cancers with a negative mesorectal fascia. CONCLUSIONS: A cutoff of 7 mm of the distance between the deepest tumor invasion and mesorectal fascia on baseline MRI can distinguish cT3 rectal cancer from a different prognosis. We recommend using the distance between the deepest tumor invasion and mesorectal fascia on baseline MRI for local and systemic risk assessment and providing a tailored schedule of neoadjuvant treatment. See Video Abstract at http://links.lww.com/DCR/B682.CORRELACIÓN ENTRE LA DISTANCIA DE LA FASCIA MESORRECTAL Y EL PRONÓSTICO DEL CÁNCER DE RECTO cT3: RESULTADOS DE UN ESTUDIO MULTICÉNTRICO DE CHINAANTECEDENTES:Los criterios de subestadificación cT3 basados en la profundidad extramural de invasión tumoral en el cáncer de recto tienen varias limitaciones.OBJETIVO:Este estudio propuso que la distancia entre la invasión tumoral más profunda y la fascia mesorrectal en la resonancia magnética preterapia puede distinguir el pronóstico de los pacientes con cT3.DISEÑO:Estudio de cohorte.ENTORNO CLINICO:El estudio incluyó una cohorte observacional, prospectiva, unicéntrica, y una cohorte de validación retrospectiva, multicéntrica e independiente.PACIENTE:Se incluyeron pacientes con cáncer de recto cT3 con fascia mesorrectal negativa sometidos a quimio-radioterapia neoadyuvante seguida de cirugía radical en cuatro centros de China desde enero de 2013 hasta septiembre de 2014.INTERVENCIÓN:Imágenes de resonancia magnética de referencia fueron medidas con la distancia entre la invasión tumoral más profunda y la fascia mesorrectal; la profundidad extramural de la invasión tumoral y el grosor del mesorrecto.PRINCIPALES MEDIDAS DE VALORACION:El límite de la distancia entre la invasión tumoral más profunda y la fascia mesorrectal se determinó mediante curvas características operativas del receptor dependientes del tiempo y se apoyó en la tasa de progresión a 5 años de la cohorte prospectiva, y luego se validó en una cohorte retrospectiva.RESULTADOS:Se incluyeron 124 y 274 pacientes en la cohorte de validación prospectiva e independiente, respectivamente. La distancia entre la invasión tumoral más profunda de la fascia mesorrectal fue el único predictor de muerte específica por cáncer (Hazard ratio: 0.1, 95% CI, 0,0-0,7); y también fue un predictor significativo de recurrencia distante Hazard ratio: 0,4, 95% CI, 0,2-0,9). No se observaron diferencias estadísticamente significativas en el pronóstico entre los pacientes clasificados como T3a/b y T3c/d.LIMITACIONES:El tamaño de la muestra es relativamente pequeño y el estudio se centró en los cánceres de recto cT3 con fascia mesorrectal negativa.CONCLUSIONES:Un límite de 7 mm de distancia entre la invasión tumoral más profunda y la fascia mesorrectal en la resonancia magnética de referencia puede distinguir el cáncer de recto cT3 de diferentes pronósticos. Recomendamos la distancia entre la invasión tumoral más profunda y la fascia mesorrectal en la resonancia magnética de referencia para la evaluación del riesgo local y sistémico, proporcionando un programa personalizado de tratamiento neoadyuvante. Consulte Video Resumen en http://links.lww.com/DCR/B682. (Traducción- Dr. Francisco M. Abarca-Rendon).


Assuntos
Imageamento por Ressonância Magnética/métodos , Invasividade Neoplásica , Protectomia , Neoplasias Retais , Reto , China/epidemiologia , Estudos de Coortes , Fáscia/diagnóstico por imagem , Fáscia/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Invasividade Neoplásica/diagnóstico por imagem , Invasividade Neoplásica/patologia , Cuidados Pré-Operatórios/métodos , Protectomia/efeitos adversos , Protectomia/métodos , Prognóstico , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Reto/diagnóstico por imagem , Reto/patologia , Reprodutibilidade dos Testes
9.
Int J Colorectal Dis ; 37(6): 1239-1249, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35503128

RESUMO

PURPOSE: Current low anterior resection syndrome (LARS) score is lagging behind and only based on clinical symptoms patient described. Preoperative imaging indicators which can be used to predict LARS is unknown. We proposed preoperative MRI parameters for identifying major LARS. METHODS: Patients receiving curative restorative anterior resection from Sept. 2007 to Sept. 2015 were collected to complete LARS score (median 75.7 months since surgery). MRI measurements associated with LARS were tested, and a multivariate logistic model was conducted for predicting LARS. Receiver operating characteristic curve was used to evaluate the model. RESULTS: Two hundred fifty-five patients undergoing neoadjuvant chemoradiotherapy and 72 patients undergoing direct surgery were enrolled. The incidence of major LARS in NCRT group was significantly higher (53.3% vs.34.7%, P = 0.005). In patients with neoadjuvant chemoradiotherapy, the thickness of ARJ (TARJ), the distance between the tumor's lower edge and anal rectal joint (DTA), and sex were independent factors for predicting major LARS; ORs were 0.382 (95% CI, 0.198-0.740), 0.653 (95% CI, 0.565-0.756), and 0.935 (95% CI, 0.915-0.955). The AUC of the multivariable model was 0.842 (95% CI, 0.794-0.890). In patients with direct surgery, only DTA was the independent factor for predicting major LARS; OR was 0.958 (95% CI, 0.930-0.988). The AUC was 0.777 (95% CI: 0.630-0.925). CONCLUSIONS: Baseline MRI measurements have the potential to predict major LARS in rectal cancer, which will benefit the decision-making and improve patients' life quality.


Assuntos
Doenças Retais , Neoplasias Retais , Humanos , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias/etiologia , Qualidade de Vida , Neoplasias Retais/complicações , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Síndrome
10.
Chin J Cancer Res ; 33(5): 606-615, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34815634

RESUMO

OBJECTIVE: To forward the magnetic resonance imaging (MRI) based distance between the deepest tumor invasion and mesorectal fascia (DMRF), and to explore its prognosis differentiation value in cT3 stage rectal cancer with comparison of cT3 substage. METHODS: This was a retrospective, multicenter cohort study including cT3 rectal cancer patients undergoing neoadjuvant chemoradiotherapy followed by radical surgery from January 2013 to September 2014. DMRF and cT3 substage were evaluated from baseline MRI. The cutoff of DMRF was determined by disease progression. Multivariate cox regression was used to test the prognostic values of baseline variables. RESULTS: A total of 804 patients were included, of which 226 (28.1%) developed progression. A DMRF cutoff of 7 mm was chosen. DMRF category, the clock position of the deepest position of tumor invasion (CDTI) and extramural venous invasion (EMVI) were independent predictors for disease progression, and hazard ratios (HRs) were 0.26 [95% confidence interval (95% CI), 0.13-0.56], 1.88 (95% CI, 1.33-2.65) and 1.57 (95% CI, 1.13-2.18), respectively. cT3 substage was not a predictor for disease progression. CONCLUSIONS: The measurement of DMRF value on baseline MRI can better distinguish cT3 rectal cancer prognosis rather than cT3 substage, and was recommended in clinical evaluation.

11.
Chin J Cancer Res ; 33(6): 682-693, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35125812

RESUMO

OBJECTIVE: Computer-aided diagnosis using deep learning algorithms has been initially applied in the field of mammography, but there is no large-scale clinical application. METHODS: This study proposed to develop and verify an artificial intelligence model based on mammography. Firstly, mammograms retrospectively collected from six centers were randomized to a training dataset and a validation dataset for establishing the model. Secondly, the model was tested by comparing 12 radiologists' performance with and without it. Finally, prospectively enrolled women with mammograms from six centers were diagnosed by radiologists with the model. The detection and diagnostic capabilities were evaluated using the free-response receiver operating characteristic (FROC) curve and ROC curve. RESULTS: The sensitivity of model for detecting lesions after matching was 0.908 for false positive rate of 0.25 in unilateral images. The area under ROC curve (AUC) to distinguish the benign lesions from malignant lesions was 0.855 [95% confidence interval (95% CI): 0.830, 0.880]. The performance of 12 radiologists with the model was higher than that of radiologists alone (AUC: 0.852 vs. 0.805, P=0.005). The mean reading time of with the model was shorter than that of reading alone (80.18 s vs. 62.28 s, P=0.032). In prospective application, the sensitivity of detection reached 0.887 at false positive rate of 0.25; the AUC of radiologists with the model was 0.983 (95% CI: 0.978, 0.988), with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 94.36%, 98.07%, 87.76%, and 99.09%, respectively. CONCLUSIONS: The artificial intelligence model exhibits high accuracy for detecting and diagnosing breast lesions, improves diagnostic accuracy and saves time.

12.
Chin J Cancer Res ; 30(2): 263-271, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29861611

RESUMO

OBJECTIVE: To study the value of high enhanced serosa sign on contrast-enhanced computed tomography (CT) in differentiating T3 from T4a gastric cancer in different Lauren classification. METHODS: This study included 276 consecutive patients with surgically confirmed pT3 or pT4a gastric cancers. The pre-operative CT images were reviewed by two radiologists blinded. The demonstration of the high enhanced serosa on CT between T3 and T4a was compared with chi-square test. The diagnostic performance of this sign on CT in the differentiation of T4a from T3 in different Lauren classification was calculated. RESULTS: The accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the judgement of serosa invasion using the high enhanced serosa sign on CT was 74.6%, 63.7%, 83.6%, 76.0% and 73.8% by one radiologist and 76.4%, 66.1%, 84.9%, 78.1% and 75.4% by the other radiologist. Compared to the intestinal-type, the sensitivity of the judgement of serosa invasion using the high enhanced serosa sign on CT in diffuse-type was significant higher (80% in both readers), while the specificity trended to be lower (65.9% and 80.5%, respectively). There is no significant difference in the accuracy of diagnosis between intestinal-type and diffuse-type of gastric cancers (the P-values of two radiologists were 0.968, 0.591, respectively). The combination of the high enhanced serosa sign with conventional CT signs is significant different in diagnosis of T3 and T4a (P<0.001). The diagnostic accuracy was increased in both radiologists after the combination. The two readers achieved substantial agreement, with Kappa coefficient of 0.63, P<0.001. CONCLUSIONS: The high enhanced serosa sign on CT is associated with serosa involvement. The sensitivity of the judgement of serosa invasion using this sign on CT in diffuse-type was significant higher than that in intestinal-type.

13.
Infect Dis Model ; 9(1): 195-203, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38293688

RESUMO

Background: China has experienced a COVID-19 wave caused by Omicron XBB variant starting in April 2023. Our aim is to conduct a retrospective analysis exploring the dynamics of the outbreak under counterfactual scenarios that combine the use of vaccines, antiviral drugs, and nonpharmaceutical interventions. Methods: We developed a mathematical model of XBB transmission in China, which has been calibrated using SARS-CoV-2 positive rates per week. Intrinsic age-specific infection-hospitalization risk, infection-ICU risk, and infection-fatality risk were used to estimate disease burdens, characterized as number of hospital admissions, ICU admissions, and deaths. Results: We estimated that in absence of behavioral change, the XBB outbreak in spring 2023 would have resulted in 0.86 billion infections (∼61% of the total population). Our counterfactual analysis shows that the synergetic effect of vaccination (70% vaccination coverage), antiviral treatment (20% receiving antiviral treatment), and moderate nonpharmaceutical interventions (20% isolation and L1 PHSMs) could reduce the number of deaths to levels close to seasonal influenza (1.17 vs. 0.65 per 10,000 individuals and 5.85 vs. 3.85 per 10,000 individuals aged 60+, respectively). The maximum peak prevalence of hospital and ICU admissions are estimated to be lower than the corresponding capacities (8.6 vs. 10.4 per 10,000 individuals and 1.2 vs. 2.1 per 10,000 individuals, respectively). Conclusion: Our findings suggest that the capacity of the Chinese healthcare system was adequate to face the Omicron XBB wave in spring 2023 but, at the same time, supports the importance of administering highly effective vaccine with long-lasting immune response, and the use of antiviral treatments.

14.
Micromachines (Basel) ; 14(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38004967

RESUMO

Femtosecond laser drilling is extensively used to create film-cooling holes in aero-engine turbine blade processing. Investigating and exploring the impact of laser processing parameters on achieving high-quality holes is crucial. The traditional trial-and-error approach, which relies on experiments, is time-consuming and has limited optimization capabilities for drilling holes. To address this issue, this paper proposes a process design method using machine learning and a genetic algorithm. A dataset of percussion drilling using a femtosecond laser was primarily established to train the models. An optimal method for building a prediction model was determined by comparing and analyzing different machine learning algorithms. Subsequently, the Gaussian support vector regression model and genetic algorithm were combined to optimize the taper and material removal rate within and outside the original data ranges. Ultimately, comprehensive optimization of drilling quality and efficiency was achieved relative to the original data. The proposed framework in this study offers a highly efficient and cost-effective solution for optimizing the femtosecond laser percussion drilling process.

15.
Cancer Imaging ; 23(1): 61, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37308928

RESUMO

BACKGROUND: The existing data on the degree of pain in patients during CT-guided percutaneous transthoracic needle biopsy (PTNB) of lung lesions are limited and the factors related to pain are unclear. In this study, we aimed to evaluate the prevalence and severity of pain reported during PTNB and to identify factors associated with increased reported pain. METHODS: Patients who underwent PTNB from April 2022 to November 2022 were prospectively evaluated using the numeric rating scale, which assesses subjective pain based on a 0-10 scoring system (0 = no pain; 10 = the worst pain imaginable). The scale divides the scores into three categories: mild pain (1-3 points), moderate pain (4-6 points), and severe pain (7-10 points). Pain scores from 4 to 10 were considered significant pain. Demographic data of patients, lesion characteristics, biopsy variables, complications, the patient's subjective feelings, and pathological result data were analyzed by multivariable logistic regression analysis to identify variables associated with significant pain. RESULTS: We enrolled 215 participants who underwent 215 biopsy procedures (mean age: 64.5 ± 9.3 years, 123 were men). The mean procedure-related pain score was 2 ± 2. Overall, 20% (43/215) of participants reported no pain (score of 0), 67.9% (146/215) reported pain scores of 1-3, 11.2% (24/215) reported scores of 4-6, and 0.9% (2/215) reported scores of 7 or higher. Furthermore, non-significant pain (scores of 0-3) was reported during 87.9% (189/215) of the procedures. In the adjusted model, significant pain was positively associated with lesions ≥ 34 mm (p = 0.001, odds ratio [OR] = 6.90; 95% confidence interval [CI]: 2.18, 21.85), a needle-pleural angle ≥ 77° (p = 0.047, OR = 2.44; 95% CI: 1.01, 5.89), and a procedure time ≥ 26.5 min (p = 0.031, OR = 3.11; 95% CI: 1.11, 8.73). CONCLUSIONS: Most participants reported no pain or mild pain from CT-guided percutaneous transthoracic needle biopsies of lung lesions. However, those with a larger lesion, a greater needle-pleural angle, and a longer procedure time reported greater pain.


Assuntos
Biópsia Guiada por Imagem , Dor , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Estudos Prospectivos , Biópsia por Agulha , Tomografia Computadorizada por Raios X , Pulmão
16.
Transl Cancer Res ; 11(4): 639-648, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35571645

RESUMO

Background: Breast-conserving surgery (BCS) is the preferred method for early breast cancer, and the accurate preoperative prediction of the feasibility of BCS can formulate the surgical plan and reduce the violation of the patient's will. The present study proposed to explore the preoperative magnetic resonance imaging (MRI) features associated with failed BCS and constructed an MRI-based model to predict BCS. Methods: This retrospective study included patients between March 2015 and July 2016, who planned to undergo BCS, had preoperative MRI examination, and had at least 2 years of follow-up. A total of 30 patients with failed BCS were identified and matched with 90 patients with successful BCS (ratio 1:3) according to age, neoadjuvant therapy, and hormone receptor expression. The patients were divided into the training group for model construction and the testing group for model validation. The MRI features, including the site of the tumor, the lesion type, and the lesion and breast volume, were compared between failure and successful BCS groups. A multivariate logistic model for predicting failed BCS was constructed using independent factors associated with failed BCS from the training group and was evaluated in the testing group. The performance of the model was evaluated using the receiver operating characteristic (ROC) curve. Results: The mean age of the cohort was 45.7±10.3 years. A significantly more non-mass lesion and multifocality, the larger volume of lesion, and the ratio of lesion and breast volume were observed in failed BCS group compared to the successful BCS group. The ratio of lesion and breast volume and multifocality were independent factors associated with failed BCS, odds ratios were 1.044 (95% CI: 1.016-1.074) and 11.161 (95% CI: 1.739-71.652), respectively. An MRI-based model for predicting failed BCS was established, the area under the ROC curves in the training and testing group were 0.902 and 0.821, respectively. Conclusions: This model might help clinicians predict failed BCS preoperatively and make an accurate surgical strategy.

17.
Abdom Radiol (NY) ; 47(4): 1232-1243, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35133470

RESUMO

PURPOSE: To explore the association between CT-detected extramural vascular invasion (ctEMVI) and lymph-vascular invasion (LVI) in colon cancer, and analyze the prognostic value of ctEMVI in different conditions of LVI. METHODS: This single-center, retrospective study included 448 colon cancer patients from January 2015 to December 2017. Preoperative CT features and clinical and pathological data were collected. Associations between ctEMVI and LVI were tested. Univariate and multivariate logistic regression was performed. Multivariate Cox regression was performed adjusted with propensity score(PS). Kaplan-Meier method was used to compare survival differences between the ctEMVI and LVI groups. A 1:1 patient pairing was conducted using PS matching to assess the prognostic effect of ctEMVI in LVI subgroups. RESULTS: Among the 448 patients, there were 261 men and 187 women, with an average age of 63 ± 12 years. The coincidence rate of ctEMVI and LVI was 73.9%. The k coefficient for identifying ctEMVI was 0.84. ctEMVI and LVI were both independent risk factors for overall survival (ctEMVI: HR 2.8, 95% CI 1.5-5.5; LVI: HR 2.2, 95% CI 1.2-4.1) and metastasis-free survival (ctEMVI: HR 3.3, 95% CI 1.7-6.4; LVI: HR 2.4, 95% CI 1.3-4.5) adjusted with PS. In the LVI(+) subgroup, the prognosis of ctEMVI(+) was significantly worse than that of ctEMVI(-); in the LVI(-) subgroup, the prognosis of different ctEMVI states was similar. CONCLUSION: ctEMVI is an independent prognostic risk factor and has different prognostic value in different LVI states. It is recommended to perform the evaluation in routine work, especially for patients with positive LVI.


Assuntos
Neoplasias do Colo , Idoso , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
18.
ACS Appl Mater Interfaces ; 14(32): 36801-36806, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35929755

RESUMO

Spatial resolution improvement has been keenly sought recently in the perovskite-based scintillation community. Here, micrometer resolution (∼2.0 µm) was achieved by using an X-ray imaging screen of self-assembled perovskite nanosheets. The assembly behavior of nanosheets was applicable to many substrates, including glass, metal, and polymer surfaces. The use of a polymer substrate not only eliminated the parasite absorption of X-ray but also enabled a flexible screen with robust bending stability. The assembly behavior, on the other hand, provided vicinity for an efficient energy transfer between nanosheets of varied thicknesses, as evidenced by both transient absorption and photoluminescence lifetime measurements. Importantly, the ensuing large Stokes shift (∼316 meV) significantly mitigated the reabsorption issue, leading to a comparable light yield to LYSO/Ce crystals. With the aid of the synchrotron-based collimated X-ray beam, the fine structure of two-dimensional objects, such as microchips, was clearly visualized with the flexible scintillation screen. Furthermore, those challenging biological samples were also scanned by phase-contrast imaging, whereby a three-dimensional reconstruction was obtained successfully. Despite the labile nature of the perovskite screen, this work represents the state-of-the-art spatial resolution for perovskite scintillation.

19.
Nat Med ; 28(7): 1468-1475, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35537471

RESUMO

Having adopted a dynamic zero-COVID strategy to respond to SARS-CoV-2 variants with higher transmissibility since August 2021, China is now considering whether, and for how long, this policy can remain in place. The debate has thus shifted towards the identification of mitigation strategies for minimizing disruption to the healthcare system in the case of a nationwide epidemic. To this aim, we developed an age-structured stochastic compartmental susceptible-latent-infectious-removed-susceptible model of SARS-CoV-2 transmission calibrated on the initial growth phase for the 2022 Omicron outbreak in Shanghai, to project COVID-19 burden (that is, number of cases, patients requiring hospitalization and intensive care, and deaths) under hypothetical mitigation scenarios. The model also considers age-specific vaccine coverage data, vaccine efficacy against different clinical endpoints, waning of immunity, different antiviral therapies and nonpharmaceutical interventions. We find that the level of immunity induced by the March 2022 vaccination campaign would be insufficient to prevent an Omicron wave that would result in exceeding critical care capacity with a projected intensive care unit peak demand of 15.6 times the existing capacity and causing approximately 1.55 million deaths. However, we also estimate that protecting vulnerable individuals by ensuring accessibility to vaccines and antiviral therapies, and maintaining implementation of nonpharmaceutical interventions could be sufficient to prevent overwhelming the healthcare system, suggesting that these factors should be points of emphasis in future mitigation policies.


Assuntos
COVID-19 , SARS-CoV-2 , Antivirais , COVID-19/epidemiologia , China/epidemiologia , Humanos
20.
medRxiv ; 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35898339

RESUMO

Background: An outbreak of COVID-19 caused by the SARS-CoV-2 Omicron BA.2 sublineage occurred in Shanghai, China from February to June 2022. The government organized multiple rounds of molecular test screenings for the entire population, providing a unique opportunity to capture the majority of subclinical infections and better characterize disease burden and the full spectrum of Omicron BA.2 clinical severity. Methods: Using daily reports from the websites of the Shanghai Municipal Health Commission, we estimated the incidence of infections, severe/critical infections, and deaths to assess the disease burden. By adjusting for right censoring and Reverse Transcription-Polymerase Chain Reaction (RT□PCR) sensitivity, we provide estimates of clinical severity, including the infection fatality risk, symptomatic case fatality risk, and risk of developing severe/critical disease upon infection. Findings: From February 26 to June 30, 2022, the overall infection rate, severe/critical infection rate, and mortality rate were 2.74 (95% CI: 2.73-2.74) per 100 individuals, 6.34 (95% CI: 6.02-6.66) per 100,000 individuals and 2.42 (95% CI: 2.23-2.62) per 100,000 individuals, respectively. The severe/critical infection rate and mortality rate increased with age with the highest rates of 125.29 (95% CI: 117.05-133.44) per 100,000 and 57.17 (95% CI: 51.63-62.71) per 100,000 individuals, respectively, noted in individuals aged 80 years or older. The overall fatality risk and risk of developing severe/critical disease upon infection were 0.09% (95% CI: 0.08-0.10%) and 0.23% (95% CI: 0.20-0.25%), respectively. Having received at least one vaccine dose led to a 10-fold reduction in the risk of death for infected individuals aged 80 years or older. Interpretation: Under the repeated population-based screenings and strict intervention policies implemented in Shanghai, our results found a lower disease burden and mortality of the outbreak compared to other settings and countries, showing the impact of the successful outbreak containment in Shanghai. The estimated low clinical severity of this Omicron BA.2 epidemic in Shanghai highlight the key contribution of vaccination and availability of hospital beds to reduce the risk of death. Funding: Key Program of the National Natural Science Foundation of China (82130093). Research in context: Evidence before this study: We searched PubMed and Europe PMC for manuscripts published or posted on preprint servers after January 1, 2022 using the following query: ("SARS-CoV-2 Omicron") AND ("burden" OR "severity"). No studies that characterized the whole profile of disease burden and clinical severity during the Shanghai Omicron outbreak were found. One study estimated confirmed case fatality risk between different COVID-19 waves in Hong Kong; other outcomes, such as fatality risk and risk of developing severe/critical illness upon infection, were not estimated. One study based on 21 hospitals across the United States focused on Omicron-specific in-hospital mortality based on a limited sample of inpatients (565). In southern California, United States, a study recruited more than 200 thousand Omicron-infected individuals and estimated the 30-day risk of hospital admission, intensive care unit admission, mechanical ventilation, and death. None of these studies estimated infection and mortality rates or other indictors associated with disease burden. Overall, the disease burden and clinical severity of the Omicron BA.2 variant have not been fully characterized, especially in populations predominantly immunized with inactivated vaccines.Added value of this study: The large-scale and multiround molecular test screenings conducted on the entire population during the Omicron BA.2 outbreak in Shanghai, leading to a high infection ascertainment ratio, provide a unique opportunity to capture the majority of subclinical infections. As such, our study provides a comprehensive assessment of both the disease burden and clinical severity of the SARS-CoV-2 Omicron BA.2 sublineage, which are especially lacking for populations predominantly immunized with inactivated vaccines.Implications of all the available evidence: We estimated the disease burden and clinical severity of the Omicron BA.2 outbreak in Shanghai in February-June 2022. These estimates are key to properly interpreting field evidence and assessing the actual spread of Omicron in other settings. Our results also provide support for the importance of strategies to prevent overwhelming the health care system and increasing vaccine coverage to reduce mortality.

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