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1.
Mod Pathol ; 36(11): 100296, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37532181

RESUMO

Deep learning systems (DLSs) have been developed for the histopathological assessment of various types of tumors, but none are suitable for differential diagnosis between follicular thyroid carcinoma (FTC) and follicular adenoma (FA). Furthermore, whether DLSs can identify the malignant characteristics of thyroid tumors based only on random views of tumor tissue histology has not been evaluated. In this study, we developed DLSs able to differentiate between FTC and FA based on 3 types of convolutional neural network architecture: EfficientNet, VGG16, and ResNet50. The performance of all 3 DLSs was excellent (area under the receiver operating characteristic curve = 0.91 ± 0.04; F1 score = 0.82 ± 0.06). Visual explanations using gradient-weighted class activation mapping suggested that the diagnosis of both FTC and FA was largely dependent on nuclear features. The DLSs were then trained with FTC images and linked information (presence or absence of recurrence within 10 years, vascular invasion, and wide capsular invasion). The ability of the DLSs to diagnose these characteristics was then determined. The results showed that, based on the random views of histology, the DLSs could predict the risk of FTC recurrence, vascular invasion, and wide capsular invasion with a certain level of accuracy (area under the receiver operating characteristic curve = 0.67 ± 0.13, 0.62 ± 0.11, and 0.65 ± 0.09, respectively). Further improvement of our DLSs could lead to the establishment of automated differential diagnosis systems requiring only biopsy specimens.


Assuntos
Adenocarcinoma Folicular , Adenoma , Aprendizado Profundo , Neoplasias da Glândula Tireoide , Humanos , Diagnóstico Diferencial , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma Folicular/diagnóstico , Adenocarcinoma Folicular/patologia , Adenoma/diagnóstico , Adenoma/patologia
2.
Eur Heart J Case Rep ; 7(3): ytad119, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36969512

RESUMO

Traumatic coronary artery dissection is a rare and challenging condition, requiring treatments for both thrombus and haemorrhage. We present a unique case of traumatic coronary artery dissection in which intra-aortic balloon pumping without heparin usage was useful in the acute traumatic phase of haemorrhagic shock with a contraindication to anti-thrombotic therapy.

3.
Int Immunol ; 29(8): 347-355, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28992181

RESUMO

The Toll family of receptors sense microbial products and activate a defense response. The molecular machinery required for the TLR response is not yet fully understood. In the present study, we used a clustered, regularly interspaced, short palindromic repeats (CRISPR)/CAS9 screening system to study TLR responses. We employed a cell line expressing TLR with an NF-κB-driven GFP reporter. The cell line was transduced with a guide RNA (gRNA) library and stimulated with TLR ligands. The cells impaired in GFP induction were sorted, and gRNAs were sequenced. Identified genes were ranked according to the count of sequence reads and the number of gRNA target sites. The screening system worked correctly, as molecules that were already known to be required for the TLR response were identified by the screening. Furthermore, this system revealed that the oligosaccharide transferase complex (OSTC) mediating co-translational glycosylation was required for TLR5, 7 and 9 responses. Protein expression of TLR5, but not an irrelevant molecule (CD44), was abolished by the lack of OSTC, suggesting the essential role of glycosylation in TLR5 protein stability. These results demonstrate that the screening system established here is able to reveal molecular mechanisms underlying the TLR response.


Assuntos
Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Retículo Endoplasmático/metabolismo , Hexosiltransferases/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Receptor 5 Toll-Like/metabolismo , Receptor 7 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Animais , Proteínas de Bactérias/genética , Proteína 9 Associada à CRISPR , Linhagem Celular , Endonucleases/genética , Genes Reporter/genética , Glicosilação , Proteínas de Fluorescência Verde/genética , Camundongos , Mutagênese , NF-kappa B/genética , Transdução de Sinais
4.
BMC Evol Biol ; 10: 339, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21050428

RESUMO

BACKGROUND: During embryonic development of segmented animals, body segments are thought to arise from the so-called "posterior growth zone" and the occurrence of this "zone" has been used to support the homology of segmentation between arthropods, annelids, and vertebrates. However, the term "posterior growth zone" is used ambiguously in the literature, mostly referring to a region of increased proliferation at the posterior end of the embryo. To determine whether such a localised posterior proliferation zone is an ancestral feature of Panarthropoda (Onychophora + Tardigrada + Arthropoda), we examined cell division patterns in embryos of Onychophora. RESULTS: Using in vivo incorporation of the DNA replication marker BrdU (5-bromo-2'-deoxyuridine) and anti-phospho-histone H3 immunolabelling, we found that a localised posterior region of proliferating cells does not occur at any developmental stage in onychophoran embryos. This contrasts with a localised pattern of cell divisions at the posterior end of annelid embryos, which we used as a positive control. Based on our data, we present a mathematical model, which challenges the paradigm that a localised posterior proliferation zone is necessary for segment patterning in short germ developing arthropods. CONCLUSIONS: Our findings suggest that a posterior proliferation zone was absent in the last common ancestor of Onychophora and Arthropoda. By comparing our data from Onychophora with those from annelids, arthropods, and chordates, we suggest that the occurrence of a "posterior growth zone" currently cannot be used to support the homology of segmentation between these three animal groups.


Assuntos
Invertebrados/embriologia , Invertebrados/crescimento & desenvolvimento , Animais , Divisão Celular , Invertebrados/citologia , Modelos Teóricos
5.
Plant Cell Physiol ; 48(2): 243-51, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17179184

RESUMO

The entire flower of Tulipa gesneriana cv. Murasakizuisho is purple, except the bottom, which is blue. To elucidate the mechanism of the different color development in the same petal, we prepared protoplasts from the purple and blue epidermal regions and measured the flavonoid composition by HPLC, the vacuolar pH by a proton-selective microelectrode, and element contents by the inductively coupled plasma (ICP) method. Chemical analyses revealed that the anthocyanin and flavonol compositions in both purple and blue colored protoplasts were the same; delphinidin 3-O-rutinoside (1) and major three flavonol glycosides, manghaslin (2), rutin (3) and mauritianin (4). The vacuolar pH values of the purple and blue protoplasts were 5.5 and 5.6, respectively, without any significant difference. However, the Fe(3+) content in the blue protoplast was approximately 9.5 mM, which was 25 times higher than that in the purple protoplasts. We could reproduce the purple solution by mixing 1 with two equimolar concentrations of flavonol with lambda(vismax) = 539 nm, which was identical to that of the purple protoplasts. Furthermore, addition of Fe(3+) to the mixture of 1-4 gave the blue solution with lambda(vismax) = 615 nm identical to that of the blue protoplasts. We have established that Fe(3+) is essential for blue color development in the tulip.


Assuntos
Compostos Férricos/química , Pigmentos Biológicos , Tulipa/fisiologia , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Ressonância Magnética Nuclear Biomolecular , Protoplastos , Espectrometria de Massas em Tandem , Tulipa/química , Vacúolos/química
6.
J Exp Bot ; 55(403): 1761-3, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15181112

RESUMO

Tobacco (Nicotiana tabacum L. cv. Xanthi XHFD8) possesses four nitrite reductase (NiR) genes: nii1, nii2, nii3, and nii4. Their differential expression in leaves and roots was investigated by quantitative competitive RT-PCR using gene-specific primer pairs. These results appear to contradict existing views on the expression of these NiR genes: (i) the mRNA of each of the four NiR genes was distinguishable both in leaves and roots; (ii) nitrate treatment increased nii1 and nii3 mRNA in leaves and roots by at least 4-fold (at least 5-fold in nii2 and nii4 mRNA); and (iii) the steady-state levels of nii1 and nii3 mRNA were almost the same in leaves (6-7 x 10(5) and about 3 x 10(6) copies microg(-1) of total RNA before and after nitrate treatment, respectively) and in roots (3-4 x 10(4) and 3-6 x 10(5) copies microg(-1) of total RNA before and after nitrate treatment, respectively). Very similar relationships were obtained for the steady-state levels of nii2 and nii4 mRNA in roots (2-4 x 10(5) and 8 x 10(6) copies microg(-1) of total RNA before and after nitrate treatment, respectively), and in leaves (5-9 x 10(4) and 4 x 10(5) copies microg(-1) of total RNA before and after nitrate treatment, respectively). These results demonstrate that nii1 and nii3 transcripts are a dominating, but not exclusive, NiR mRNA in leaves, and the same is true for nii2 and nii4 transcripts in roots.


Assuntos
Regulação da Expressão Gênica de Plantas , Nicotiana/genética , Nitrito Redutases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Família Multigênica , Nitrito Redutases/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , RNA Mensageiro/genética
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