west china medical publishers
Keyword
  • Title
  • Author
  • Keyword
  • Abstract
Advance search
Advance search

Search

find Keyword "mutation" 100 results
  • A heart sound classification method based on complete ensemble empirical modal decomposition with adaptive noise permutation entropy and support vector machine

    Heart sound signal is a kind of physiological signal with nonlinear and nonstationary features. In order to improve the accuracy and efficiency of the phonocardiogram (PCG) classification, a new method was proposed by means of support vector machine (SVM) in which the complete ensemble empirical modal decomposition with adaptive noise (CEEMDAN) permutation entropy was as the eigenvector of heart sound signal. Firstly, the PCG was decomposed by CEEMDAN into a number of intrinsic mode functions (IMFs) from high to low frequency. Secondly, the IMFs were sifted according to the correlation coefficient, energy factor and signal-to-noise ratio. Then the instantaneous frequency was extracted by Hilbert transform, and its permutation entropy was constituted into eigenvector. Finally, the accuracy of the method was verified by using a hundred PCG samples selected from the 2016 PhysioNet/CinC Challenge. The results showed that the accuracy rate of the proposed method could reach up to 87%. In comparison with the traditional EMD and EEMD permutation entropy methods, the accuracy rate was increased by 18%–24%, which demonstrates the efficiency of the proposed method.

    Release date:2022-06-28 04:35 Export PDF Favorites Scan
  • Screening for mt-DNA mutations in optic neuritis of unknown reason

    Purpose To investigate mitochondrial DNA (mt-DNA) mutations in optic neuritis of unknow reason (ONUR) and to assess the pathogenic and differential diagnostic values of screening for mt-DNA mutations in ONUR. Method Thirty patients with ONUR were screened for mt-DNA mutations by using SSCP,mutation-specific primer PCR and sequencing. Results mt-DNA mutations were found in 12 out of the thirty patients.All of the mutations were at 11778 position,but no one at 3460 and 15257. Conclusions Quite a number of patients (12/30,40%) with ONUR were caused actually by mt-DNA mutation.Screening for mt-DNA mutation in these patients has a pathogenic and differential diagnostic significance. (Chin J Ocul Fundus Dis,2000,16:78-79) 

    Release date:2016-09-02 06:05 Export PDF Favorites Scan
  • Relation between disulfidptosis-related genes and prognosis or immunotherapy of pancreatic cancer: based on bioinformatics analysis

    ObjectiveTo investigate the relation between disulfidptosis-related genes (DRGs) and prognosis or immunotherapy response of patients with pancreatic cancer (PC). MethodsThe transcriptome data, somatic mutation data, and corresponding clinical information of the patients with PC in The Cancer Genome Atlas (TCGA) were downloaded. The DRGs mutated in the PC were screened out from the 15 known DRGs. The DRGs subtypes were identified by consensus clustering algorithm, and then the relation between the identified DRGs subtypes and the prognosis of patients with PC, immune cell infiltration or functional enrichment pathway was analyzed. Further, a risk score was calculated according to the DRGs gene expression level, and the patients were categorized into high-risk and low-risk groups based on the mean value of the risk score. The risk score and overall survival of the patients with high-risk and low-risk were compared. Finally, the relation between the risk score and (or) tumor mutation burden (TMB) and the prognosis of patients with PC was assessed. ResultsThe transcriptome data and corresponding clinical information of the 177 patients with PC were downloaded from TCGA, including 161 patients with somatic mutation data. A total of 10 mutated DRGs were screened out. Two DRGs subtypes were identified, namely subtype A and subtype B. The overall survival of PC patients with subtype A was better than that of patients with subtype B (χ2=8.316, P=0.003). The abundance of immune cell infiltration in the PC patients with subtype A was higher and mainly enriched in the metabolic and conduction related pathways as compaired with the patients with subtype B. The mean risk score of 177 patients with PC was 1.921, including 157 cases in the high-risk group and 20 cases in the low-risk group. The risk score of patients with subtype B was higher than that of patients with subtype A (t=14.031, P<0.001). The overall survival of the low-risk group was better than that of the high-risk group (χ2=17.058, P<0.001), and the TMB value of the PC patients with high-risk was higher than that of the PC patients with low-risk (t=5.642, P=0.014). The mean TMB of 161 patients with somatic mutation data was 2.767, including 128 cases in the high-TMB group and 33 cases in the low-TMB group. The overall survival of patients in the high-TMB group was worse than that of patients in the low-TMB group (χ2=7.425, P=0.006). ConclusionDRGs are closely related to the prognosis and immunotherapy response of patients with PC, and targeted treatment of DRGs might potentially provide a new idea for the diagnosis and treatment of PC.

    Release date:2023-11-24 10:51 Export PDF Favorites Scan
  • Identification of mutation of the X-linked juvenile retinoschisis gene

    Objective To analyze the pathogenesy and mutation of X-linked juvenile retinoschisis (XLRS) 1 gene in XLRS families, and to provide the theory basis in directing gene diagnosis. Methods The mutation of XLRS1 gene code in two XLRS families were detected and screened by polymerase chain reaction (PCR) and DNA direct sequence determination. Results Pro193Ser mutation was detected in family 1. Conclusion Pro193Ser mutation could be found in XLRS families, which can be used for genetic consultation and prenatal gene diagnosis. (Chin J Ocul Fundus Dis,2004,20:149-151)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • Study on Expression of BRAF Gene and Invasiveness of Papillary Thyroid Carcinoma

    ObjectiveTo study the expressions of BRAF gene in papillary thyroid microcarcinoma (PTMC) and papillary thyroid carcinoma (PTC) >1 cm in diameter, and the invasiveness of PTMC and PTC. MethodsThe data of 275 patients with PTC received surgical treatment and with BRAF gene mutation results in West China Hospital of Sichuan University from 2011 September to 2013 September were retrospectively analyzed. According to the size of tumors, the patients were divided into three groups, was the diameter <1 cm group, 1 cm< diameter≤2 cm group, and diameter >2 cm group,respectively. The ratio of BRAF gene mutation, and the degree of risk of extrathyroidal invasion and lymph node metastasis were compared. ResultsUnivariate analysis showed that tumor size was not related with the age, gender, and BRAF gene mutation rate (P>0.05), while the tumor size was related with the extrathyroidal invasion and lymph node metastasis (P<0.05), and the ratio of BRAF gene mutation was related with the extrathyroidal invasion and lymph node metastasis (P<0.05). Multivariate analysis showed that tumor size was associated with extrathyroidal extension (P=0.009) and lymph node metastasis (P=0.000). ConclusionsBRAF gene mutation can increase the extrathyroidal invasion and lymph node metastasis risk of PTC, and it is no significantly correlated with tumor size of PTC. The invasiveness of PTC increases with the increased of tumor size, but the PTMC of BRAF gene mutation positive is still require positive treatment.

    Release date: Export PDF Favorites Scan
  • THE RELATION OF THE LOSS OF HETEROZYGOSITY AND MUTATION FOR nm23-H1 WITH THE INHIBITION OF METASTASIS IN COLORECTAL CARCINOMA

    The loss of heterozygosity and mutation for nm23-H1 gene in colorectal carcinomas were studied by Southern blot and RT-PCR-SSCP/silver staining sequencing. The rate of loss of heterozygosity for nm23-H1 was 29.63%. The cases of Duke’s stage D and distant metastatsis had higher frequency of the loss of heterozygosity. No mutation for nm23-H1 was found in colorectal carcinomas. These reaults indicate that the loss of heterozygosity for nm23-H1 may play a significant role in the malignant progression and distant metastasis in colorectal carcinomas.

    Release date:2016-08-29 09:18 Export PDF Favorites Scan
  • Research progress on KRAS mutation in pancreatic tumorigenesis and pancreatic cancer therapy

    ObjectiveTo summarize the research progress of KRAS mutation in pancreatic tumorigenesis and therapy.MethodThe research progress of KRAS mutation in pancreatic tumorigenesis and therapy were summarized by reading the domestic and international literatures published in recent years.ResultsPancreatic cancer had the title of " king of cancer”. More than 90% of pancreatic cancer patients had KRAS mutation. KRAS had a complex relationship with pancreatic cancer through downstream signaling pathways, including Raf (rapidly accelerated fibrosarcoma)-mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK), phosphatidylinositol-4, 5-bisphosphate 3-kinase (PI3K)-protein kinase B (AKT), and RalGDS-Ral. Although basic research on pancreatic cancer was deepening, there was still a lack of effective molecular targeted drugs.ConclusionsKRASgene plays an important role in the occurrence of pancreatic cancer. The treatment associated with KRAS mutation provides a more effective prognostic possibility for pancreatic cancer patients.

    Release date:2019-06-05 04:24 Export PDF Favorites Scan
  • Analysis of the gene mutation of vitelline macular dystrophy in a family with Best disease

    Objective To analyze the relationship between genotype and phenotype of vitelline macular dystrophia (VMD2) gene in a family with Best disease, and to provide the theoretical basis for gene diagnosis of Best disease. Methods Mutation in the coding regions and the promotor sequence of VMD2 gene from 10 members in a family with Best disease were screened by polymerase chain reaction (PCR) and direct DNA sequencing, and combined with a conformation sensitive gel electrophoresis (CSGE) approach, VMD2 gene screening was performed on 100 normal control individuals. Results In the 10 members, Trarr;C nucleotide change at the 223 base of exon 3 was detected in 9, including 6 with Best disease who was confirmed by ophthalmoscopy and electrophysiological examination in whom 2 were affirmed as having homozygote of this mutation. Other 3 young family members with VMD2 gene mutation only had abnormal electro-oculogram manifestations. Above mutation was not detected in the normal control individuals. Conclusions The phenotype and genotype of VMD2 in the family with Best disease is highly correlated. Mutation in VMD2 gene is the nosogenesis in this family. Mutation screening of VMD2 gene can be used for genic diagnosis and genetic consultation of Best disease. (Chin J Ocul Fundus Dis, 2006, 22: 86-89)

    Release date:2016-09-02 05:51 Export PDF Favorites Scan
  • Advancements in ophthalmological research on Waardenburg syndrome

    Waardenburg syndrome is a rare genetic disease of auditory pigmentation. The main symptom is sensorineural hearing loss. Pigment disorders and other developmental defects in skin, hair, iris, fundus and other parts are specifically divided into four different subtypes, each of which corresponds to different pathogenic genes, which encode transcription factors and signaling molecules that play a key role in the development process of neural crest cells into melanocytes. Because there are multiple subtypes of Waardenburg syndrome, different subtypes exhibit different symptoms, signs and ocular manifestations. Patients with Waardenburg syndrome are often first treated in ENT head and neck surgery due to hearing loss. Lack of theoretical knowledge related to Waardenburg syndrome by ophthalmologists may lead to misdiagnosis or missed diagnosis. Although there are currently limited treatments for the disease, with the continuous development of gene therapy and hearing management methods, the future treatment prospects will be broader.

    Release date:2024-07-16 02:36 Export PDF Favorites Scan
  • Effect of RAS gene mutation on survival after liver metastasis resection for patients with colorectal cancer combined with liver metastasis: integrated analysis

    ObjectiveTo evaluate effect of RAS gene mutation after liver metastasis resection on overall survival (OS) and disease-free survival (DFS) for patients with colorectal cancer combined with liver metastasis. MethodsA comprehensive and systematic literature search in the PubMed and other databases was conducted, with the final search ending on January 5, 2022. The impact of RAS gene mutation after liver metastasis resection on survival of patients with colorectal cancer combined with liver metastasis was analyzed by the Stata 12.0 software and Review Manager version 5.3 software, meanwhile which were analyzed according to subgroups, including study type (retrospective and prospective studies), region (Asian and European), and number of RAS gene mutation sites (>2 and ≤2). ResultsA total of 26 studies with 13 356 patients were included. The integrated analysis results showed that the patients with RAS mutations had statistically shorter OS [HR=1.54, 95%CI (1.43, 1.65), P<0.001] and DFS [HR=1.32, 95%CI (1.19, 1.44), P<0.001] as compared with RAS wild-type. Except the 1-year overall survival rate, the 2–5-year overall survival rate and 1–5-year disease-free survival rate of patients with RAS gene mutation were statistically lower than those of patients with RAS wild-type (P<0.05). The results of subgroup analysis showed that no matter retrospective and prospective studies, as well as studies in Asian and European countries, it was found that the OS and DFS for patients with RAS gene mutation were shorter than those of patients with wild-type (P<0.05); At the same time, subgroup analysis of the number of RAS gene mutation sites showed that OS and DFS of patients with number of mutation sites >2 were shortened as compared with ≤2 (P<0.05). ConclusionFrom the overall analysis results, the survival of patients with RAS gene mutation after liver metastasis resection is worse than that of patients with RAS wild-type for patients with colorectal cancer combined with liver metastasis.

    Release date:2023-02-02 08:55 Export PDF Favorites Scan
10 pages Previous 1 2 3 ... 10 Next

Format

Content