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1.
Ann Hum Genet ; 82(5): 304-308, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30039856

RESUMO

Cockayne syndrome (CS) is one the rare DNA-repair deficiency disorders with autosomal recessive inheritance. Failure to thrive and microcephaly are the major criteria of diagnosis. Owing to genetic heterogeneity of CS, whole exome sequencing is promising way to determine the genetic basis of the disease. Here, we present c.1053delT in ERCC8 gene in an Iranian family with symptom of CS using whole exome sequencing. The deletion was novel and was not previously reported elsewhere.


Assuntos
Síndrome de Cockayne/genética , Enzimas Reparadoras do DNA/genética , Deleção de Sequência , Fatores de Transcrição/genética , Sequência de Aminoácidos , Criança , Feminino , Humanos , Irã (Geográfico) , Masculino , Linhagem , Sequenciamento do Exoma
2.
Radiography (Lond) ; 28(3): 732-738, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35410707

RESUMO

INTRODUCTION: In late 2019 and after the COVID-19 pandemic in the world, many researchers and scholars tried to provide methods for detecting COVID-19 cases. Accordingly, this study focused on identifying patients with COVID-19 from chest X-ray images. METHODS: In this paper, a method for diagnosing coronavirus disease from X-ray images was developed. In this method, DenseNet169 Deep Neural Network (DNN) was used to extract the features of X-ray images taken from the patients' chests. The extracted features were then given as input to the Extreme Gradient Boosting (XGBoost) algorithm to perform the classification task. RESULTS: Evaluation of the proposed approach and its comparison with the methods presented in recent years revealed that this method was more accurate and faster than the existing ones and had an acceptable performance for detecting COVID-19 cases from X-ray images. The experiments showed 98.23% and 89.70% accuracy, 99.78% and 100% specificity, 92.08% and 95.20% sensitivity in two and three-class problems, respectively. CONCLUSION: This study aimed to detect people with COVID-19, focusing on non-clinical approaches. The developed method could be employed as an initial detection tool to assist the radiologists in more accurate and faster diagnosing the disease. IMPLICATION FOR PRACTICE: The proposed method's simple implementation, along with its acceptable accuracy, allows it to be used in COVID-19 diagnosis. Moreover, the gradient-based class activation mapping (Grad-CAM) can be used to represent the deep neural network's decision area on a heatmap. Radiologists might use this heatmap to evaluate the chest area more accurately.


Assuntos
COVID-19 , Aprendizado Profundo , COVID-19/diagnóstico por imagem , Teste para COVID-19 , Humanos , Redes Neurais de Computação , Pandemias , SARS-CoV-2 , Raios X
3.
Iran J Ped Hematol Oncol ; 5(4): 170-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26985349

RESUMO

BACKGROUND: The aim of this study was the ex vivo expansion of Umbilical Cord Blood hematopoietic stem cells on biocompatible nanofiber scaffolds. MATERIALS AND METHODS: CD133+ hematopoietic stem cells were separated from umbilical cord blood using MidiMacs (positive selection) system by means of monocolonal antibody CD133 (microbeads); subsequently, flowcytometry method was done to assess the purity of separated cells. Isolated cells were cultured on plate (2 Dimensional) and fibronectin conjugated polyethersulfon nanofiber scaffold, simultaneously (3 Dimensional). Colony assay test was performed to show colonization ability of expanded cells. RESULTS: Cell count analysis revealed that expansion of hematopoietic stem cells in 2dimensional (2D) environment was greater than 3dimensional (3D) condition (p= 0.01). Assessment of stem cell- phenotype after expansions was performed by flowcytometric analysis which is showed that the maintenance of CD133 marker in expanded cells in 3 dimensional condition were higher than expanded cells in 2 dimensional condition (p=0.01). Moreover, colony assay test was performed before and after of expansion to show colonization ability of expanded cells both in 3D and 2D culture and results revealed more ability of 3D culture compared with 2D culture (p= 0.03). CONCLUSION: The results of current study confirmed that umbilical cord blood CD133+ haematopoietic stem cells are able to expand on fibronectin conjugated polyethersulfon scaffold. These findings indicated that 3D is a proper and valuable cell culture system for hematopoietic stem cells expansion, compared to 2D in invitro situation.

4.
Nat Prod Res ; 22(14): 1225-1230, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18932085

RESUMO

Lapachones are pharmaceutically active compounds generating reactive oxygen species. The crystal structure and redox behaviour of the title lapachones, derivates of quinones, were determined by X-ray diffraction and cyclovoltametric measurements. The observed results were compared with beta-lapachone.


Assuntos
Cristalografia por Raios X/métodos , Eletroquímica/métodos , Naftoquinonas/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular
5.
J Clin Lab Anal ; 19(6): 229-32, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16302208

RESUMO

Different approaches have been used to extract DNA from whole blood. In most of these methods enzymes (such as proteinase K and RNAse A) or toxic organic solvents (such as phenol or guanidine isothiocyanate) are used. Since these enzymes are expensive, and most of the materials that are used routinely are toxic, it is desirable to apply an efficient DNA extraction procedure that does not require the use of such materials. In this study, genomic DNA was extracted by the salting-out method, but instead of using an analytical-grade enzyme and chemical detergents, as normally used for DNA isolation, a common laundry powder was used. Different concentrations of the powder were tested, and proteins were precipitated by NaCl-saturated distilled water. Finally, DNA precipitation was performed with the use of 96% ethanol. From the results, we conclude that the optimum concentration of laundry powder for the highest yield and purity of isolated DNA is 30 mg/mL. The procedure was optimized, and a final protocol is suggested. Following the same protocol, DNA was extracted from 100 blood samples, and their amounts were found to be >50 microg/mL of whole blood. The integrity of the DNA fragments was confirmed by agarose gel electrophoresis. Furthermore, the extracted DNA was used as a template for PCR reaction. The results obtained from PCR showed that the final solutions of extracted DNA did not contain any inhibitory material for the enzyme used in the PCR reaction, and indicated that the isolated DNA was of good quality. These results show that this method is simple, fast, safe, and cost-effective, and can be used in medical laboratories and research centers.


Assuntos
DNA/isolamento & purificação , Detergentes/química , DNA/sangue , Genômica/métodos , Humanos , Reação em Cadeia da Polimerase , Cloreto de Sódio/química
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