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1.
Med Image Anal ; 88: 102833, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37267773

RESUMO

In-utero fetal MRI is emerging as an important tool in the diagnosis and analysis of the developing human brain. Automatic segmentation of the developing fetal brain is a vital step in the quantitative analysis of prenatal neurodevelopment both in the research and clinical context. However, manual segmentation of cerebral structures is time-consuming and prone to error and inter-observer variability. Therefore, we organized the Fetal Tissue Annotation (FeTA) Challenge in 2021 in order to encourage the development of automatic segmentation algorithms on an international level. The challenge utilized FeTA Dataset, an open dataset of fetal brain MRI reconstructions segmented into seven different tissues (external cerebrospinal fluid, gray matter, white matter, ventricles, cerebellum, brainstem, deep gray matter). 20 international teams participated in this challenge, submitting a total of 21 algorithms for evaluation. In this paper, we provide a detailed analysis of the results from both a technical and clinical perspective. All participants relied on deep learning methods, mainly U-Nets, with some variability present in the network architecture, optimization, and image pre- and post-processing. The majority of teams used existing medical imaging deep learning frameworks. The main differences between the submissions were the fine tuning done during training, and the specific pre- and post-processing steps performed. The challenge results showed that almost all submissions performed similarly. Four of the top five teams used ensemble learning methods. However, one team's algorithm performed significantly superior to the other submissions, and consisted of an asymmetrical U-Net network architecture. This paper provides a first of its kind benchmark for future automatic multi-tissue segmentation algorithms for the developing human brain in utero.


Assuntos
Processamento de Imagem Assistida por Computador , Substância Branca , Gravidez , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Cabeça , Feto/diagnóstico por imagem , Algoritmos , Imageamento por Ressonância Magnética/métodos
2.
Asian J Surg ; 45(11): 2172-2178, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35346584

RESUMO

BACKGROUND: Computed tomography (CT) imaging can help to predict the pathological invasiveness of early-stage lung adenocarcinoma and guide surgical resection. This retrospective study investigated whether CT imaging could distinguish pre-invasive lung adenocarcinoma from IAC. It also compared final pathology prediction accuracy between CT imaging and intraoperative frozen section analysis. METHODS: This study included 2093 patients with early-stage peripheral lung adenocarcinoma who underwent CT imaging and intraoperative frozen section analysis between March 2013 and November 2014. Nodules were classified as ground-glass (GGNs), part-solid (PSNs), and solid nodules according to CT findings; they were classified as pre-IAC and IAC according to final pathology. Univariate, multivariate, and receiver operating characteristic (ROC) curve analyses were performed to evaluate whether CT imaging could distinguish pre-IAC from IAC. The concordance rates of CT imaging and intraoperative frozen section analyses with final pathology were also compared to determine their accuracies. RESULTS: Multivariate analysis identified tumor size as an independent distinguishing factor. ROC curve analyses showed that the optimal cut-off sizes for distinguishing pre-IAC from IAC for GGNs, PSNs, and solid nodules were 10.79, 11.48, and 11.45 mm, respectively. The concordance rate of CT imaging with final pathology was significantly greater than the concordance rate of intraoperative frozen section analysis with final pathology (P = 0.041). CONCLUSION: CT imaging could distinguish pre-IAC from IAC in patients with early-stage lung adenocarcinoma. Because of its accuracy in predicting final pathology, CT imaging could contribute to decisions associated with surgical extent. Multicenter standardized trials are needed to confirm the findings in this study.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/cirurgia , Estudos de Coortes , Secções Congeladas , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Invasividade Neoplásica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
3.
Radiat Oncol ; 15(1): 186, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736567

RESUMO

BACKGROUND: To investigate predictors of pathological invasiveness and prognosis of lung adenocarcinoma in patients with pure ground-glass nodules (pGGNs). METHODS: Clinical and computed tomography (CT) features of invasive adenocarcinomas (IACs) and pre-IACs were retrospectively compared in 641 consecutive patients with pGGNs and confirmed lung adenocarcinomas who had undergone postoperative CT follow-up. Potential predictors of prognosis were investigated in these patients. RESULTS: Of 659 pGGNs in 641 patients, 258 (39.1%) were adenocarcinomas in situ, 265 (40.2%) were minimally invasive adenocarcinomas, and 136 (20.6%) were IACs. Respective optimal cutoffs for age, serum carcinoembryonic antigen concentration, maximal diameter, mean diameter, and CT density for distinguishing pre-IACs from IACs were 53 years, 2.19 ng/mL, 10.78 mm, 10.09 mm, and - 582.28 Hounsfield units (HU). Univariable analysis indicated that sex, age, maximal diameter, mean diameter, CT density, and spiculation were significant predictors of lung IAC. In multivariable analysis age, maximal diameter, and CT density were significant predictors of lung IAC. During a median follow-up of 41 months no pGGN IACs recurred. CONCLUSIONS: pGGNs may be lung IACs, especially in patients aged > 55 years with lesions that are > 1 cm in diameter and exhibit CT density > - 600 HU. pGGN IACs of < 3 cm in diameter have good post-resection prognoses.


Assuntos
Adenocarcinoma de Pulmão/patologia , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/patologia , Nódulo Pulmonar Solitário/patologia , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico por imagem
4.
Medicine (Baltimore) ; 96(49): e8928, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29245257

RESUMO

RATIONALE: Endometrial stromal sarcoma (ESS) is rare, representing only approximately 0.2% of all uterine malignancies. Mixed type endometrial carcinomas (MT-ECs) are rare tumors with both type I and II features, and are difficult to diagnose. Cases of ESS and MT-ECs coexisting in the same patient are extremely rare. This study aimed to describe a case of ESS in combination with MT-ECs in a 47-year-old premenopausal woman. PATIENT CONCERNS: A woman presented to the hospital complaining of occasional abdominal pain and had high tumor markers: cancer antigen (CA) 19-9 (263.6 U/mL) and CA 125 (428.0 U/mL). Transvaginal ultrasound examination revealed a complex mass (12.3 × 9.1 × 6.3 cm) with solid and cystic components on the right rear wall of the uterus. Abdominopelvic computed tomography images showed a pelvic cystic-solid mixed mass. The patient underwent an exploratory midline laparotomy. The mass was hypothesized to be malignant on the uterine posterior wall. Tumor deposits were found on bilateral parametrium. On peritoneal implantation, multiple metastases were seen on the serosal surface of the bowel and greater omentum. A frozen section revealed a spindle cell sarcoma. DIAGNOSES: Pathological reports following surgery revealed concurrent ESS and MT-ECs. INTERVENTIONS: The patient underwent a total abdominal hysterectomy, bilateral salpingo-oophorectomy, total omentectomy, and macroscopic clearance of the tumor. Adjuvant chemotherapy was given. OUTCOMES: The patient was still alive when this report was written. LESSONS: Considering the rarity of ESS in combination with MT-ECs, this study presented an overview of the literature and discussed a number of histological and clinical issues. Nevertheless, etiology and pathogenesis of these tumors need further investigation.


Assuntos
Neoplasias do Endométrio/diagnóstico , Sarcoma do Estroma Endometrial/diagnóstico , Sarcoma/diagnóstico , Neoplasias Uterinas/diagnóstico , Biomarcadores Tumorais/sangue , Diagnóstico Diferencial , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Histerectomia , Pessoa de Meia-Idade , Ovariectomia , Salpingo-Ooforectomia , Sarcoma/patologia , Sarcoma/cirurgia , Sarcoma do Estroma Endometrial/patologia , Sarcoma do Estroma Endometrial/cirurgia , Tomografia Computadorizada por Raios X , Ultrassonografia , Neoplasias Uterinas/patologia , Neoplasias Uterinas/cirurgia
5.
Clin Transplant ; 28(10): 1194-201, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25328058

RESUMO

INTRODUCTION: When adult-to-adult living donor liver transplantation (LDLT) using the right lobe is carried out, there is disagreement between different centers as to whether the middle hepatic vein (MHV) is included or retained by the donor. METHODS: Ninety-two cases of adult-to-adult LDLT were performed between January 2007 and December 2010 using a right lobe graft. A protocol for MHV allocation was applied according to the donor's remnant liver volume, overall graft/recipient weight ratio (GRWR), and anatomic characteristics of the hepatic vein. Among these cases, there were 44 cases with MHV and 48 cases without MHV. No blood products were used during donor operations, and there was no occurrence of death or small-for-size syndrome after operations. RESULTS: There were statistical differences between Groups I and II according to the ages of the recipients, the actual GRWR, the weights of grafts, the cold storage time of grafts, etc. All patients recovered smoothly; one-, three-, and five-yr survival rates of patients were 96.7%, 92.4%, and 92.4% and of grafts were 95.7%, 91.3%, and 91.3%, respectively. CONCLUSION: With a reasonable allocation protocol and precise evaluation, either MHV harvested or MHV retained to the donor during adult-to-adult LDLT using the right lobe can achieve good outcome.


Assuntos
Veias Hepáticas/patologia , Veias Hepáticas/cirurgia , Transplante de Fígado , Fígado/irrigação sanguínea , Doadores Vivos , Adolescente , Adulto , Idoso , Algoritmos , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
6.
Immunobiology ; 216(6): 678-85, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21122941

RESUMO

Regulatory T (Treg) cells constitute a unique T-cell lineage that plays a pivotal role in the maintenance of the peripheral tolerance. The transcription factor Foxp3 (Forkhead box P3) was identified as a master regulator for the development and function of Treg cells. It is well defined that Foxp3 expression is critical to program CD4+CD25+ Treg cell development and function; however, the molecular mechanisms that are involved in the regulation of the Foxp3 expression remain unclear. Recent studies have showed an indication that this process is influenced by a number of transcription factors. In this review, we summarize the current knowledge of how Foxp3 expression is controlled at molecular level by focusing on these factors.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Transcrição Gênica/imunologia , Animais , Fatores de Transcrição Forkhead/genética , Humanos , Sequências Reguladoras de Ácido Nucleico/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Transcrição Gênica/genética
7.
Acta Biomater ; 5(1): 453-61, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18675601

RESUMO

The structural organization of natural liver is instrumental in the multifunctionality of hepatocytes, and mimicking these specific architectures in tissue-engineered scaffold plays an important role in the engineering of an implantable liver equivalent in vitro. To achieve this goal, we have developed a novel fabrication process to create chitosan-gelatin hybrid scaffolds with well-organized architectures and highly porous structures by combining rapid prototyping, microreplication and freeze-drying techniques. The scaffolds obtained not only have analogous configurations of portal vein, central vein, flow-channel network and hepatic chambers, but also have high (>90%) porosity, with the mean pore size of 100microm. Swelling and degradation studies showed that the scaffold has excellent properties of hydrophilicity and biodegradability. A hepatocyte culture experiment was conducted to evaluate the efficiency of the well-defined chitosan-gelatin scaffold in facilitating hepatocyte growth in the inner layer of the scaffold in vitro. Scanning electron microscopy and histological analysis showed that hepatocytes could form large colonies in the predefined hepatic chambers, and these cavities could the completely filled with hepatocytes during 7 day culture. Albumin secretion and urea synthesis further indicated that the well-organized scaffolds were more suitable for hepatocyte culture.


Assuntos
Materiais Biocompatíveis/química , Técnicas de Cultura de Células/instrumentação , Quitosana/química , Gelatina/química , Fígado/metabolismo , Engenharia Tecidual/métodos , Animais , Biodegradação Ambiental , Técnicas de Cultura de Células/métodos , Proliferação de Células , Liofilização , Hepatócitos/citologia , Fígado/patologia , Masculino , Porosidade , Ratos , Ratos Sprague-Dawley
8.
Transpl Immunol ; 17(2): 120-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17306743

RESUMO

To gain transplantation tolerance between donor organs and hosts is the ultimate goal of all sorts of organ transplantations. Induction of regulatory T cells has been demonstrated to lead to transplantation tolerance. This paper will review subsets of regulatory T cells, the role and mechanisms of CD4(+)CD25(+) regulatory T cells (Tregs) in graft rejection and tolerance, pathway used by Tregs to recognized alloantigens, pathways of Tregs homing into the graft and effects of immunosuppression on Tregs. It was well known that Tregs play a pivotal role in transplantation tolerance. The mechanisms by which Tregs exert their regulatory effect in the induction and maintenance of transplantation tolerance, anthropogenically, consist of physical cell-to-cell contact with potential target cells, autocrine and paracrine properties. ICAM-1, TGF-beta, CTLA-4, GITR and OX40 (CD134), etc. are involved in the regulatory function of Tregs through cell-to-cell contact mechanism. IL-10 and TGF-beta are two important soluble mediators involved in the autocrine mechanism by which Tregs exert their regulatory function. Paracrine properties refer to re-educate potentially destructive alloresponsive T cells to gain regulatory function. All that discussed above could illustrate, at least partially, how naturally occurring Tregs exert their regulatory function in vivo as they constitute only 5-10% of peripheral CD4(+) T cells.


Assuntos
Rejeição de Enxerto/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante , Antígenos CD4/análise , Humanos , Subunidade alfa de Receptor de Interleucina-2/análise
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