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1.
Pediatr Radiol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937304

RESUMO

BACKGROUND: Cervical lymphadenopathy is common in children and has diverse causes varying from benign to malignant, their similar manifestations making differential diagnosis difficult. OBJECTIVE: This study aimed to investigate whether radiomic models using conventional magnetic resonance imaging (MRI) could classify pediatric cervical lymphadenopathy. METHODS: A total of 419 cervical lymph nodes from 146 patients, and encompassing four common etiologies (Kikuchi disease, reactive hyperplasia, suppurative lymphadenitis and malignancy), were randomly divided into training and testing sets in a ratio of 7:3. For each lymph node, 1,218 features were extracted from T2-weighted images. Then, the least absolute shrinkage and selection operator (LASSO) models were used to select the most relevant ones. Two models were built using a support vector machine classifier, one was to classify benign and malignant lymph nodes and the other further distinguished four different diseases. The performance was assessed by receiver operating characteristic curves and decision curve analysis. RESULTS: By LASSO, 20 features were selected to construct a model to distinguish benign and malignant lymph nodes, which achieved an area under the curve (AUC) of 0.89 and 0.80 in the training and testing sets, respectively. Sixteen features were selected to construct a model to distinguish four different cervical lymphadenopathies. For each etiology, Kikuchi disease, reactive hyperplasia, suppurative lymphadenitis, and malignancy, an AUC of 0.97, 0.91, 0.88, and 0.87 was achieved in the training set, and an AUC of 0.96, 0.80, 0.82, and 0.82 was achieved in the testing set, respectively. CONCLUSION: MRI-derived radiomic analysis provides a promising non-invasive approach for distinguishing causes of cervical lymphadenopathy in children.

2.
Mar Life Sci Technol ; 5(4): 478-491, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38045548

RESUMO

The evolution of a two-chambered heart, with an atrium and a ventricle, has improved heart function in both deuterostomes (vertebrates) and some protostomes (invertebrates). Although studies have examined the unique structure and function of these two chambers, molecular comparisons are few and limited to vertebrates. Here, we focus on the two-chambered protostome heart of the mollusks, offering data that may provide a better understanding of heart evolution. Specifically, we asked if the atrium and ventricle differ at the molecular level in the mollusk heart. To do so, we examined two very different species, the giant African land snail (Lissachatina fulica) and the relatively small, aquatic yesso scallop (Mizuhopecten yessoensis), with the assumption that if they exhibited commonality these similarities would likely reflect those across the phylum. We found that, although the hearts of these two species differed histologically, their cardiac gene function enrichments were similar, as revealed by transcriptomic analysis. Furthermore, the atrium and ventricle in each species had distinct gene function clusters, suggesting an evolutionary differentiation of cardiac chambers in mollusks. Finally, to explore the relationship between vertebrate and invertebrate two-chambered hearts, we compared our transcriptomic data with published data from the zebrafish, a well-studied vertebrate model with a two-chambered heart. Our analysis indicated a functional similarity of ventricular genes between the mollusks and the zebrafish, suggesting that the ventricle was differentiated to achieve the same functions in invertebrates and vertebrates. As the first such study on protostomes, our findings offered initial insights into how the two-chambered heart arose, including a possible understanding of its occurrence in both protostomes and deuterostomes. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00202-0.

3.
Cells ; 12(4)2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36831240

RESUMO

Ribosomal proteins (RPs) constitute the ribosome, thus participating in the protein biosynthesis process. Emerging studies have suggested that many RPs exhibit different expression levels across various tissues and function in a context-dependent manner for animal development. Drosophila melanogaster RpS3 encodes the ribosomal protein S3, one component of the 40S subunit of ribosomes. We found that RpS3 is highly expressed in the reproductive organs of adult flies and its depletion in male germline cells led to severe defects in sperm production and male fertility. Immunofluorescence staining showed that RpS3 knockdown had little effect on early germ cell differentiation, but strongly disrupted the spermatid elongation and individualization processes. Furthermore, we observed abnormal morphology and activity of mitochondrial derivatives in the elongating spermatids of RpS3-knockdown testes, which could cause the failure of axoneme elongation. We also found that RpS3 RNAi inhibited the formation of the individualization complex that takes charge of disassociating the spermatid bundle. In addition, excessive apoptotic cells were detected in the RpS3-knockdown testes, possibly to clean the defective spermatids. Together, our data demonstrated that RpS3 plays an important role in regulating spermatid elongation and individualization processes and, therefore, is required for normal Drosophila spermatogenesis.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Proteínas Ribossômicas , Animais , Masculino , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas Ribossômicas/metabolismo , Sêmen/metabolismo , Espermatogênese
4.
Am J Hematol ; 87(2): 219-21, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22189875

RESUMO

Graft versus host disease (GVHD) is a common complication of allogeneic transplant. Acute GVHD primarily affects the skin, liver, and GI tract generally within the first 100 days after transplant. GVHD following an allogeneic transplant occurs as a result of donor T-cell recognition of host alloantigens. In contrast, patients undergoing ASCT are not subjected to the genetic disparity that occurs with allogeneic transplant, and in principal, should not develop this proinflammatory response. A clinical syndrome, however, has been described in patients following autologous transplant that shares the same features as GVHD occurring in recipients post-allogeneic transplant [1-3]. Previously reported cases have described skin, liver, and GI tract manifestations consistent with what is seen in allogeneic GVHD. Biopsies of the skin and GI tract mucosa have demonstrated similar histological features as well. Interestingly, the majority of reported cases seem to occur in patients with multiple myeloma undergoing consolidative ASCT. Historically, however, these patients have been described as having a relatively benign course with mild skin rash, nausea, vomiting, and/or diarrhea that is responsive to immunosuppression. In this article, we present a case of fatal, spontaneous GVHD in a patient with multiple myeloma following ASCT.


Assuntos
Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/patologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Mieloma Múltiplo/patologia , Evolução Fatal , Feminino , Trato Gastrointestinal/patologia , Doença Enxerto-Hospedeiro/imunologia , Humanos , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Pele/patologia , Transplante Autólogo
5.
Proc Natl Acad Sci U S A ; 101(6): 1775-80, 2004 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-14736918

RESUMO

The switch from vegetative to reproductive development in plants necessitates a switch in the developmental program of the descendents of the stem cells in the shoot apical meristem. Genetic and molecular investigations have demonstrated that the plant-specific transcription factor and meristem identity regulator LEAFY (LFY) controls this developmental transition by inducing expression of a second transcription factor, APETALA1, and by regulating the expression of additional, as yet unknown, genes. Here we show that the additional LFY targets include the APETALA1-related factor, CAULIFLOWER, as well as three transcription factors and two putative signal transduction pathway components. These genes are up-regulated by LFY even when protein synthesis is inhibited and, hence, appear to be direct targets of LFY. Supporting this conclusion, cis-regulatory regions upstream of these genes are bound by LFY in vivo. The newly identified LFY targets likely initiate the transcriptional changes that are required for the switch from vegetative to reproductive development in Arabidopsis.


Assuntos
Genoma de Planta , Proteínas de Plantas/genética , Proteínas de Homeodomínio/genética , Fenômenos Fisiológicos Vegetais , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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