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1.
Acta Obstet Gynecol Scand ; 102(8): 1026-1033, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37318036

RESUMO

INTRODUCTION: Cytology-based triaging is commonly used to manage the care of women with positive human papillomavirus (HPV) results, but it suffers from subjectivity and a lack of sensitivity and reproducibility. The diagnostic performance of an artificial intelligence-enabled liquid-based cytology (AI-LBC) triage approach remains unclear. Here, we compared the clinical performance of AI-LBC, human cytologists and HPV16/18 genotyping at triaging HPV-positive women. MATERIAL AND METHODS: HPV-positive women were triaged using AI-LBC, human cytologists and HPV16/18 genotyping. Histologically confirmed cervical intraepithelial neoplasia grade 2/3 or higher (CIN2+/CIN3+) were accepted as thresholds for clinical performance assessments. RESULTS: Of the 3514 women included, 13.9% (n = 489) were HPV-positive. The sensitivity of AI-LBC was comparable to that of cytologists (86.49% vs 83.78%, P = 0.744) but substantially higher than HPV16/18 typing at detecting CIN2+ (86.49% vs 54.05%, P = 0.002). While the specificity of AI-LBC was significantly lower than HPV16/18 typing (51.33% vs 87.17%, P < 0.001), it was significantly higher than cytologists at detecting CIN2+ (51.33% vs 40.93%, P < 0.001). AI-LBC reduced referrals to colposcopy by approximately 10%, compared with cytologists (51.53% vs 60.94%, P = 0.003). Similar patterns were also observed for CIN3+. CONCLUSIONS: AI-LBC has equivalent sensitivity and higher specificity compared with cytologists, with more efficient colposcopy referrals for HPV-positive women. AI-LBC could be particularly useful in regions where experienced cytologists are few in number. Further investigations are needed to determine triaging performance through prospective designs.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Gravidez , Neoplasias do Colo do Útero/patologia , Estudos Transversais , Papillomavirus Humano 16/genética , Triagem/métodos , Infecções por Papillomavirus/diagnóstico , Inteligência Artificial , Reprodutibilidade dos Testes , Papillomavirus Humano 18/genética , Displasia do Colo do Útero/patologia , Colposcopia , Detecção Precoce de Câncer/métodos
2.
Mod Pathol ; 36(8): 100186, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37059230

RESUMO

Population-based cervical cytology screening techniques are demanding and laborious and have relatively poor diagnostic accuracy. In this study, we present a cytologist-in-the-loop artificial intelligence (CITL-AI) system to improve the accuracy and efficiency of abnormal cervical squamous cell detection in cervical cancer screening. The artificial intelligence (AI) system was developed using 8000 digitalized whole slide images, including 5713 negative and 2287 positive cases. External validation was performed using an independent, multicenter, real-world data set of 3514 women, who were screened for cervical cancer between 2021 and 2022. Each slide was assessed using the AI system, which generated risk scores. These scores were then used to optimize the triaging of true negative cases. The remaining slides were interpreted by cytologists who had varying degrees of experience and were categorized as either junior or senior specialists. Stand-alone AI had a sensitivity of 89.4% and a specificity of 66.4%. These data points were used to establish the lowest AI-based risk score (ie, 0.35) to optimize the triage configuration. A total of 1319 slides were triaged without missing any abnormal squamous cases. This also reduced the cytology workload by 37.5%. Reader analysis found CITL-AI had superior sensitivity and specificity compared with junior cytologists (81.6% vs 53.1% and 78.9% vs 66.2%, respectively; both with P < .001). For senior cytologists, CITL-AI specificity increased slightly from 89.9% to 91.5% (P = .029); however, sensitivity did not significantly increase (P = .450). Therefore, CITL-AI could reduce cytologists' workload by more than one-third while simultaneously improving diagnostic accuracy, especially compared with less experienced cytologists. This approach could improve the accuracy and efficiency of abnormal cervical squamous cell detection in cervical cancer screening programs worldwide.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Inteligência Artificial , Esfregaço Vaginal/métodos , Detecção Precoce de Câncer/métodos , Células Epiteliais/patologia
3.
Polymers (Basel) ; 15(5)2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36904546

RESUMO

Plastic film capacitors are widely used in pulse and energy storage applications because of their high breakdown strength, high power density, long lifetime, and excellent self-healing properties. Nowadays, the energy storage density of commercial biaxially oriented polypropylene (BOPP) is limited by its low dielectric constant (~2.2). Poly(vinylidene fluoride) (PVDF) exhibits a relatively high dielectric constant and breakdown strength, making it a candidate material for electrostatic capacitors. However, PVDF presents significant losses, generating a lot of waste heat. In this paper, under the guidance of the leakage mechanism, a high-insulation polytetrafluoroethylene (PTFE) coating is sprayed on the surface of a PVDF film. The potential barrier at the electrode-dielectric interface is raised by simply spraying PTFE and reducing the leakage current, and then the energy storage density is increased. After introducing the PTFE insulation coating, the high-field leakage current in the PVDF film shows an order of magnitude reduction. Moreover, the composite film presents a 30.8% improvement in breakdown strength, and a 70% enhancement in energy storage density is simultaneously achieved. The all-organic structure design provides a new idea for the application of PVDF in electrostatic capacitors.

4.
Shanghai Kou Qiang Yi Xue ; 30(2): 214-218, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-34109366

RESUMO

PURPOSE: To investigate the 5-year survival and complication rates of implants placed in grafted sinuses with different surgical approaches and analyze the causes for failure. METHODS: This study retrospectively observed the prognosis of patients who underwent maxillary sinus augmentation by means of lateral window technique(LWT) or transalveolar osteotomy technique (TOT) and simultaneously installed implants performed, in Hefei Stomatological Hospital. The primary predictor variables were surgical approaches, including LWT and TOT. The primary outcome measurement was the 5-year implant survival rate, complication rates and failure causes. Potential confounders included diabetes, age at surgery, gender, smoking habit, oral hygiene, tooth position, length and diameter of implants and type of prosthesis. Chi-square test and logistic regression analysis were performed with SPSS 21.0 software package. RESULTS: Fifty-nine patients (31 males and 28 females), installed with 93 implants, with a mean age of (61.3±10.1) years old, were enrolled. Over (5±1.2) years of follow-up, five implants failed, with a total survival rate of 94.6%. In detail, there were 3 failed implants in the LWT group and 2 failed implants in the TOT group, for a survival rate of 85.7% and 97.2%, respectively. Chi-square test showed that smoking habit (P=0.010), oral hygiene(P=0.037) as well as operative approach(P=0.040) were significantly associated with the final survival rates, multivariate logistic regression analysis displayed that smoking habit (OR=0.030, 95%CI: 0.002-0.493, P=0.014) was still associated with the finial survival rates. Surgical approach(P=0.025) was markedly related to causes for the failed implants. Of which, three (100%) failed implants in the LWT group was due to poor osseointegration and implant mobility 3 months after sinus augmentation, and 2(100%) in the TOT group was because of persistent peri-implantitis and loss of the graft or alveolar bone 4 years after sinus augmentation. Smoking habit was also significantly relevant to complication rates(P=0.014), and the occurrence incidence of controllable peri-implantitis in patient having a smoking habit was relatively higher, accounting for 6.8%(6/88), compared with patients without smoking habit. Significant relationship between surgical approaches and implant complications was not observed(P=0.051). CONCLUSIONS: Different surgical approaches for maxillary sinus augmentation do not significantly correlate with implant survival rates and implant complications. However, surgical approach is markedly related to the causes of failed implants. Smoking will lead to a decreased implant survival rate and controllable peri-implantitis.


Assuntos
Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Idoso , Implantação Dentária Endóssea , Falha de Restauração Dentária , Feminino , Seguimentos , Humanos , Masculino , Maxila/cirurgia , Seio Maxilar/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Levantamento do Assoalho do Seio Maxilar/efeitos adversos , Resultado do Tratamento
5.
Cancer Cytopathol ; 129(9): 693-700, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33826796

RESUMO

BACKGROUND: Cervical cytology screening is usually laborious with a heavy workload and poor diagnostic consistency. The authors have developed an artificial intelligence (AI) microscope that can provide onsite diagnostic assistance for cervical cytology screening in real time. METHODS: A total of 2167 cervical cytology slides were selected from a cohort of 10,601 cases from Shenzhen Maternity and Child Healthcare Hospital, and the training data set consisted of 42,073 abnormal cervical epithelial cells. The recognition results of an AI technique were presented in a microscope eyepiece by an augmented reality technique. Potentially abnormal cells were highlighted with binary classification results in a 10× field of view (FOV) and with multiclassification results according to the Bethesda system in 20× and 40× FOVs. In addition, 486 slides were selected for the reader study to evaluate the performance of the AI microscope. RESULTS: In the reader study, which compared manual reading with AI assistance, the sensitivities for the detection of low-grade squamous intraepithelial lesions and high-grade squamous intraepithelial lesions were significantly improved from 0.837 to 0.923 (P < .001) and from 0.830 to 0.917 (P < .01), respectively; the κ score for atypical squamous cells of undetermined significance (ASCUS) was improved from 0.581 to 0.637; the averaged pairwise κ of consistency for multiclassification was improved from 0.649 to 0.706; the averaged pairwise κ of consistency for binary classification was improved from 0.720 to 0.798; and the averaged pairwise κ of ASCUS was improved from 0.557 to 0.639. CONCLUSIONS: The results of this study show that an AI microscope can provide real-time assistance for cervical cytology screening and improve the efficiency and accuracy of cervical cytology diagnosis.


Assuntos
Células Escamosas Atípicas do Colo do Útero , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Inteligência Artificial , Biologia Celular , Detecção Precoce de Câncer , Feminino , Humanos , Gravidez , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal
6.
EJNMMI Res ; 3: 51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23841937

RESUMO

BACKGROUND: Many biological factors of 2-[(18) F]fluoro-2-deoxy-d-glucose ((18) F-FDG) in blood can affect (18) F-FDG uptake in tumors. In this study, longitudinal (18) F-FDG positron emission tomography (PET) studies were performed on tumor-bearing mice to investigate the effect of blood glucose level and tumor size on (18) F-FDG uptake in tumors. METHODS: Six- to eight-week-old severe combined immunodeficiency mice were implanted with glioblastoma U87 (n = 8) or adenocarcinoma MDA-MB-231 (MDA) (n = 11) in the shoulder. When the tumor diameter was approximately 2.5 mm, a 60-min dynamic (18) F-FDG PET scan was performed weekly until the tumor diameter reached 10 mm. Regions of interests were defined in major organs and tumor. A plasma curve was derived based on a modeling method that utilizes the early heart time-activity curve and a late-time blood sample. The (18) F-FDG uptake constant K i was calculated using Patlak analysis on the tumors without an apparent necrotic center shown in the PET images. For each tumor type, the measured K i was corrected for partial volume (PV), and multivariate regression analysis was performed to examine the effects of blood glucose level ([Glc]) and tumor growth. Corrected Akaike's information criterion was used to determine the best model. RESULTS: The regression model that best fit the PV-corrected K i for U87 data was K i /RC = (1/[Glc]) × (0.27 ± 0.027) mL/min/mL (where [Glc] is in mmol/L), and for MDA, it was K i /RC = (0.04 ± 0.005) mL/min/mL, where K i /RC denotes the PV-corrected K i using an individual recovery coefficient (RC). The results indicated that (18) F-FDG K i /RC for U87 was inversely related to [Glc], while [Glc] had no effect on (18) F-FDG K i /RC of MDA. After the effects of PV and [Glc] were accounted for, the data did not support any increase of (18) F-FDG K i as the tumor (of either type) grew larger in size. CONCLUSIONS: The effect of [Glc] on the tumor (18) F-FDG K i was tumor-dependent. PV- and [Glc]-corrected (18) F-FDG K i did not show significant increase as the tumor of either type grew in size.

7.
J Mater Chem B ; 1(39)2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24409342

RESUMO

There has been extensive research on the use of nanovectors for cancer therapy. Targeted delivery of nanotherapeutics necessitates two important characteristics; the ability to accumulate at the disease locus after overcoming sequential biological barriers and the ability to carry a substantial therapeutic payload. Successful combination of the above two features is challenging, especially in solid porous materials where chemical conjugation of targeting entities on the particle surface will generally prevent successful loading of the therapeutic substance. In this study, we propose a novel strategy for decorating the surface of mesoporous silicon particles with targeting entities (bacteriophage) and gold nanoparticles (AuNP) while maintaining their payload carrying potential. The resulting Bacteriophage Associated Silicon Particles (BASP) demonstrates efficient encapsulation of macromolecules and therapeutic nanoparticles into the porous structures. In vitro targeting data show enhanced targeting efficiency with about four orders of magnitude lower concentration of bacteriophage. In vivo targeting data suggest that BASP maintain their integrity following intravenous administration in mice and display up to three fold higher accumulation in the tumor.

8.
Arch Biochem Biophys ; 295(1): 49-54, 1992 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-1315506

RESUMO

Proteins in human red cell hemolysate were purified to determine which of them increase inhibition of the Na,K-ATPase in the presence of 2 microM free Ca. Samples purified 600,000-fold inhibited the Na,K-ATPase of human red cells in a Ca-dependent manner and stimulated the (Ca+Mg)-ATPase. These samples contained two proteins as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE): calmodulin (18,000 Mr), which comprised most (greater than 90%) of the total protein, and an unidentified protein of approximately 13,000 Mr. Both proteins were a distinctive light yellow when stained with silver. Calmodulin from bovine testes also inhibited the Na,K-ATPase and stimulated the (Ca+Mg)-ATPase. This preparation also contained two proteins as analyzed by SDS-PAGE: calmodulin (95 to 99% of the total protein) and another protein of approximately 13,000 Mr (1 to 5% of the total protein). Both were light yellow when stained with silver. Since the amount of red cell protein was limited, the remainder of the study was carried out with the bovine testes preparation. Heating the testes preparation decreased, but did not abolish, inhibition of the Na,K-ATPase and reduced stimulation of the (Ca+Mg)-ATPase. When corrected for denatured calmodulin, both heated and unheated proteins increased inhibition of the Na,K-ATPase to the same extent. The Na,K-ATPase was inhibited at 2 microM free Ca in a dose-dependent manner over a range of 15 to 100 nM calmodulin. To establish if the inhibition was due to the calmodulin or the 13,000 Mr protein, both were electroeluted after SDS-PAGE. Electroeluted calmodulin stimulated the (Ca+Mg)-ATPase and increased Ca inhibition of the Na,K-ATPase. Electroeluted amounts of the smaller Mr protein slightly stimulated the (Ca+Mg)-ATPase, but had no effect on the Na,K-ATPase. This protein was digested with cyanogen bromide, partially sequenced, and thereby identified as a fragment of calmodulin. We conclude that intact calmodulin increases inhibition of the Na,K-ATPase at 2 microM free Ca. We suggest that calmodulin is part of a mechanism mediating the effects of physiological free Ca on the Na,K-ATPase.


Assuntos
Cálcio/farmacologia , Calmodulina/farmacologia , Eritrócitos/enzimologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Sequência de Aminoácidos , Animais , ATPase de Ca(2+) e Mg(2+)/efeitos dos fármacos , ATPases Transportadoras de Cálcio/efeitos dos fármacos , Calmodulina/genética , Bovinos , Relação Dose-Resposta a Droga , Eritrócitos/química , Humanos , Masculino , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Proteínas/isolamento & purificação , Homologia de Sequência do Ácido Nucleico , ATPase Trocadora de Sódio-Potássio/efeitos dos fármacos , Testículo/química
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