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101.
BackgroudCoenzyme Q10 (CoQ10) is involved in the biosynthesis of adenosine triphosphate (ATP), and is most abundant in the mitochondrial membrane. The primary CoQ10 deficiency caused by COQ2 defect is mostly manifested as encephalopathy, encephalopathy with nephropathy, and rarely as an isolated nephrotic syndrome.MethodsClinical and pathological data and peripheral blood samples of 2 siblings with steroid-resistant nephrotic syndrome (SRNS) and their family members of a Chinese pedigree were collected. DNA was extracted and subjected to next-generation sequencing of target genes of hereditary nephropathy.ResultsCompound heterozygous mutations of COQ2 (c.1058A > G, p.Y353C, paternal and c.973A > G, p.T325A, maternal)were identified in both siblings of the pedigree. Mutation of p.Y353C was novel. The proband was a girl, who presented with SRNS at the age of 7 months. CoQ10 was administered after the gene sequencing results came out. Proteinuria decreased gradually to 1+, occasionally negative. The child was normal in growth and intelligence. She is now 4 years old. The second patient was her elder brother. He was found to have SRNS at the age of 2 years old. Renal pathology indicated focal segmental glomerulosclerosis (FSGS). Electronic microcopy revealed that a large quantity of mitochondria with normal contour was accumulated within the podocytes. Both patients were in normal intelligence without convulsion.ConclusionThe 2 cases harboring COQ2compound heterozygous mutations presented with isolated SRNS, with a renal pathology of FSGS and a large quantity of mitochondria with normal contour accumulated within the podocytes. CoQ10 was efficacy in eliminating proteinuria.  相似文献   
102.
BackgroundMutation-positive patients who develop unilateral breast cancer require different treatments, such as prophylactic mastectomy of the contralateral breast, from those used for other breast cancer patients. If a mutation is found before surgery, it is necessary to consider a surgical procedure that includes reconstruction. For BRCA mutation-positive patients, a suitable treatment must be selected. In Japan, a test for BRCA mutation has been covered by health insurance since 2020, making it possible to preoperatively test patients who are suspected of being positive. We report a case of simultaneous bilateral breast cancer that was found to be BRCA mutation-positive preoperatively and underwent bilateral subcutaneous mastectomy and breast reconstruction.Case presentationA 57-year-old woman was admitted to our hospital after a breast cancer screening revealed a mass in the left breast. She had a family history of breast cancer, including her sister, aunt, and cousin. She was suspected of being malignant with a mass on both sides of her breast on imaging. She underwent needle biopsy and was diagnosed as having bilateral invasive ductal carcinoma, for which she was placed on preoperative chemotherapy. Due to the strong family history of bilateral breast cancer, the patient was recommended to undergo a BRCA gene-mutation test and she consented. The result was positive for BRCA1 mutation. Although it was judged that bilateral breast-conserving surgery was sufficiently possible, bilateral subcutaneous mastectomy and breast reconstruction were performed based on BRCA mutation-positive status.DiscussionPerforming a preoperative BRCA test may change the surgical procedure.BRCA tests are beneficial to patients, but the timing of the tests is important. Care must be taken not to force the patient.ConclusionsKnowing whether the patient is BRCA mutation-positive is extremely important for selecting surgical procedures and treatment methods. BRCA testing should be recommended for patients who are strongly suspected of being positive, but the decision should be the patient’s. It is therefore necessary to provide accurate information and engage in a dialogue with the patient, but the medical staff should not pressure the patient to have the test.  相似文献   
103.
BackgroundHepatocellular carcinoma (HCC) is one of the most common causes of cancer worldwide. Although many studies have focused on oncogene characteristics, the genomic landscape of Chinese HCC patients has not been fully clarified.MethodsA total of 165 HCC patients, including 146 males and 19 females, were enrolled. The median age was 55 years (range, 27–78 years). Corresponding clinical and pathological information was collected for further analysis. A total of 168 tumor tissues from these patients were selected for next-generation sequencing (NGS)-based 450 panel gene sequencing. Genomic alterations including single nucleotide variations (SNV), short and long insertions and deletions (InDels), copy number variations, and gene rearrangements were analyzed. Tumor mutational burden (TMB) was measured by an algorithm developed in-house. The top quartile of HCC was classified as TMB high.ResultsA total of 1,004 genomic alterations were detected from 258 genes in 168 HCC tissues. TMB values were identified in 160 HCC specimens, with a median TMB of 5.4 Muts/Mb (range, 0–28.4 Muts/Mb) and a 75% TMB of 7.7 Muts/Mb. The most commonly mutated genes were TP53, TERT, CTNNB1, AXIN1, RB1, TSC2, CCND1, ARID1A, and FGF19. SNV was the most common mutation type and C:G>T:A and guanine transformation were the most common SNVs. Compared to wild-type patients, the proportion of Edmondson grade III–IV and microvascular invasion was significantly higher in TP53 mutated patients (P<0.05). The proportion of tumors invading the hepatic capsule was significantly higher in TERT mutated patients (P<0.05). The proportion of Edmondson grade I-II, alpha fetoprotein (AFP) <25 µmg/L, and those without a history of hepatitis B was significantly higher in CTNNB1 mutated patients (P<0.05). CTNNB1 mutations were associated with TMB high in HCC patients (P<0.05). Based on correlation analysis, the mutation of TP53 was independently correlated with microvascular invasion (P=0.002, OR =3.096) and Edmondson grade III–IV (P=0.008, OR =2.613). The mutation of TERT was independently correlated with tumor invasion of the liver capsule (P=0.001, OR =3.030), and the mutation of CTNNB1 was independently correlated with AFP (<25 µmg/L) (P=0.009, OR =3.414).ConclusionsThe most frequently mutated genes of HCC patients in China were TP53, TERT, and CTNNB1, which mainly lead to the occurrence and development of HCC by regulating the P53 pathway, Wnt pathway, and telomere repair pathway. There were more patients with microvascular invasion and Edmondson III–IV grade in TP53 mutated patients and more patients with hepatic capsule invasion in TERT mutated patients, while in CTNNB1 mutated patients, there were more patients with Edmondson I–II grade, AFP <25 µmg/L, and a non-hepatitis B background. Also, the TMB values were significantly higher in CTNNB1 mutated patients than in wild type patients.  相似文献   
104.
袁丹  张燕  李一平  李玲  周玚  苏玲  叶黎  杨洪  梁姝 《现代预防医学》2021,(21):3967-3973
目的 分析四川省接受艾滋病抗病毒治疗6~12个月病毒学失败患者的耐药影响因素和耐药特征。方法 对2016—2019年接受治疗6~12个月且病毒学失败患者进行HIV-1基因型耐药检测,采用统计学logistic回归和卡方检验分析病毒学失败患者耐药发生的影响因素,以及不同地区和亚型毒株间耐药突变特征。结果 3626例患者符合调查标准,成功获得序列2915例(80.39%),其中1246(42.74%)例耐药,多因素logistic回归分析发现,注射吸毒者的耐药突变是异性性传播患者的1.90倍;艾滋病的耐药突变是HIV感染者的1.75倍;基线CD4+T淋巴细胞计数≥350个/μl和200~349个/μl的耐药突变是CD4+T淋巴细胞计数<200个μl的0.76和0.64倍;初始治疗方案含洛匹那韦/利托那韦(LPV/r)的二线治疗方案的耐药突变是是含齐多夫定的0.37倍;感染CRF01_AE亚型毒株的耐药突变是感染CRF07_BC亚型毒株的1.34倍。成都平原、川东北、川西北、川南和攀西地区耐药率分别为45.41%、37.47%、54.84%、43.38和34.34%,卡方检验有统计学意义(P<0.05);主要流行亚型CRF07_BC、CRF01_E、CRF08_BC和CRF85_BC耐药率分别为39.60%、48.55%、34.17%和44.27%,卡方检验有统计学意义(P<0.05)。结论 四川治疗6~12个月艾滋病患者病毒学失败的耐药率较高,耐药突变状况复杂多样,感染途径、基线CD4+T淋巴细胞计数、病程、感染毒株亚型、初始治疗方案是治疗6~12个月病毒学失败患者发生耐药的影响因素,且各地区耐药发生和各亚型耐药突变特征不同。  相似文献   
105.
Comparison of spontaneous mutation spectra derived from different transgenic constructs can provide valuable insights for interpreting the mechanisms of spontaneous mutation. In this study, spontaneous mutation frequencies and spectra of the lacI transgene are compared in the liver of C57BL/6, B6C3F1, and BC-1 mice and F344 rats. Before correction for clonal expansion, the mutant frequency varied from 2.6 +/- 0.45 to 5.0 +/- 2.4 x 10(-5). Correction for potential clonal expansion reduced the range in mutation frequency to between 2.3 +/- 0.45 and 3.5 +/- 2.0 x 10(-5). There is thus no statistical difference in spontaneous mutation frequency between the different strains and species. G:C --> A:T transitions and to a lesser extent, G:C --> T:A transversions dominate the mutational spectra in all of these animals. In three strains of mice, G:C --> A:T transitions account for 50.7-53.3% of mutation, 81.7-83.8% of which involve CpG sites, whereas G:C --> T:A transversions account for 17.8-32.9% of mutations with 43.2-50.0% found at CpG sites. In rats, G:C --> A:T transitions account for 38.0% of the spectra, 70.0% of which involve CpG sites, whereas G:C --> T:A transversions account for 23.0% of the spectra, 70.0% of which involve CpG sites. The distribution of other classes of mutations is also very similar. We conclude that, despite reports about species and strain differences in induced mutation, spontaneous mutations in the lacI transgene appear to be similar, regardless of genomic location, rodent strain, or species. In addition to insights into spontaneous mutation, this study also provides essential data for comparison with and interpretation of induced mutations.  相似文献   
106.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation.  相似文献   
107.
目的:了解抑癌基因p53在人食管癌及其癌旁组织中的突变,尤其是p53外显子4的变异。方法:采用PCR-SSCP和DNA测序等方法对24例人食管鳞状细胞癌术后标本进行了p53基因外显子4-8的突变分析。结果:在食管癌组织及癌旁组织幸免被检测的15列标本中,分别有40.0%(6/15)和46.7%(7/15)发生了突变,两者差异无显著性,食管癌组织标本中有50%(9/18)的突变发生在外显子4。另外,有4例在食管癌组织及癌旁组织中同时检测出p53基因突变,年龄,性别,术前治疗(放射治疗,化学药物治疗),肿瘤的部位等对癌组织的突变率并不产生影响。结论:在人食管癌及其癌旁组织中,p53基因的突变几率差异无显著性,年龄,性子4的突变可能产生了尤为重要的作用。  相似文献   
108.
血清HBV DNA与乙肝病型及e系统之间关系探讨   总被引:1,自引:0,他引:1  
目的 探讨血清HBV DNA与乙肝病型及e系统之间的关系。方法 采用PCR法对310例乙肝病毒携带者及乙肝患者进行血清HBV DNA检测,同时用ELISA法进行乙肝标志物测定。结果 各病型HBV DNA阳性率以慢性肝炎和无症状携带者最高,与急性肝炎肝硬变组比较差异显著;HBeAg阳性病例中HBV DNA阳性率以无症状携带者,急性肝炎、慢性肝炎(轻)组最高,与慢性肝炎(中)、肝硬变组比较差异显著;在  相似文献   
109.
目的 :探讨共济失调毛细血管扩张症 (AT)基因突变与食管癌及结肠癌发病的关系。方法 :运用PCR SSCP及DNA同位素测序等技术 ,对 17例食管癌和 15例结肠癌患者的AT基因第 41~ 5 1外显子进行突变检测。结果 :15例结肠癌标本的SSCP带型与正常对照组织无差异 ;17例食管癌标本中有 1例SSCP带型比正常对照组织多一条带 ,测序发现 ,该例标本在AT基因第 49外显子发生单碱基缺失。结论 :AT基因突变可能与某些类型的食管癌发病有关 ,但尚不能判断与结肠癌的相关性  相似文献   
110.
子宫内膜腺癌P53蛋白与基因突变的研究   总被引:1,自引:0,他引:1  
目的 研究p^53基因突变对子宫内膜腺癌临床病理特点及转归的影响。方法 运用免疫组化染色和聚合酶联反应-单链构象多态性分析(PCR-SSCP),检测子宫内膜腺癌患者P53的蛋白表达与基因突变。结果 子宫内膜腺癌患者P53蛋白表达阳性率为34.15%,阳性者5年存活率明显低于阴性者(P=0.037),核过表达仅与组织分化相关,而与患者年龄、分期、浸肌程度、淋巴结转移、附件转移均无关(P〉0.05);  相似文献   
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