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Osteoarthritis (OA) is the most common type of arthritis characterized by progressive cartilage degradation, with its pathogenesis closely related to chondrocyte autophagy. Chondrocytes are the only cells in articular cartilage, and the function of chondrocytes plays a vital role in maintaining articular cartilage homeostasis. Autophagy, an intracellular degradation system that regulates energy metabolism in cells, plays an incredibly important role in OA. During the early stages of OA, autophagy is enhanced in chondrocytes, acting as an adaptive mechanism to protect them from various environmental changes. However, with the progress of OA, chondrocyte autophagy gradually decreases, leading to the accumulation of damaged organelles and macromolecules within the cell, prompting chondrocyte apoptosis. Numerous studies have shown that cartilage degradation is influenced by the senescence and apoptosis of chondrocytes, which are associated with reduced autophagy. The relationship between autophagy, senescence, and apoptosis is complex. While autophagy is generally believed to inhibit cellular senescence and apoptosis to promote cell survival, recent studies have shown that some proteins are degraded by selective autophagy, leading to the secretion of the senescence-associated secretory phenotype (SASP) or increased SA-ß-Gal activity in senescent cells within the damaged region of human OA cartilage. Autophagy activation may lead to different outcomes depending on the timing, duration, or type of its activation. Thus, our study explored the complex relationship between chondrocyte autophagy and OA, as well as the related regulatory molecules and signaling pathways, providing new insights for the future development of safe and effective drugs targeting chondrocyte autophagy to improve OA.
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BACKGROUND: Portal vein thrombosis (PVT), a complication of liver cirrhosis, is a major public health concern. PVT prediction is the most effective method for PVT diagnosis and treatment. AIM: To develop and validate a nomogram and network calculator based on clinical indicators to predict PVT in patients with cirrhosis. METHODS: Patients with cirrhosis hospitalized between January 2016 and December 2021 at the First Hospital of Lanzhou University were screened and 643 patients with cirrhosis who met the eligibility criteria were retrieved. Following a 1:1 propensity score matching 572 patients with cirrhosis were screened, and relevant clinical data were collected. PVT risk factors were identified using the least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression analysis. Variance inflation factors and correlation matrix plots were used to analyze multicollinearity among the variables. A nomogram was constructed to predict the probability of PVT based on independent risk factors for PVT, and its predictive performance was verified using a receiver operating characteristic curve (ROC), calibration curves, and decision curve analysis (DCA). Finally, a network calculator was constructed based on the nomograms. RESULTS: This study enrolled 286 cirrhosis patients with PVT and 286 without PVT. LASSO analysis revealed 13 variables as strongly associated with PVT occurrence. Multivariate logistic regression analysis revealed nine indicators as independent PVT risk factors, including etiology, ascites, gastroesophageal varices, platelet count, D-dimer, portal vein diameter, portal vein velocity, aspartate transaminase to neutrophil ratio index, and platelet-to-lymphocyte ratio. LASSO and correlation matrix plot results revealed no significant multicollinearity or correlation among the variables. A nomogram was constructed based on the screened independent risk factors. The nomogram had excellent predictive performance, with an area under the ROC curve of 0.821 and 0.829 in the training and testing groups, respectively. Calibration curves and DCA revealed its good clinical performance. Finally, the optimal cutoff value for the total nomogram score was 0.513. The sensitivity and specificity of the optimal cutoff values were 0.822 and 0.706, respectively. CONCLUSION: A nomogram for predicting PVT occurrence was successfully developed and validated, and a network calculator was constructed. This can enable clinicians to rapidly and easily identify high PVT risk groups.
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BACKGROUND: The incidence of colorectal cancer among the middle-aged and elderly is gradually increasing in China. Colonoscopy is an effective method for the early diagnosis of colorectal cancer, and bowel preparation is one of many important factors affecting colonoscopy. Although there are many studies on intestinal cleansers, the results are not ideal. There is evidence that hemp seed oil has certain potential effects in intestinal cleansing, but prospective studies on this topic are still lacking. METHODS: This is a randomized, double-blind, single-center clinical study. We randomly assigned 690 participants to groups each administered 3 L of polyethylene glycol (PEG), 30 mL of hemp seed oil and 2 L of PEG, or 30 mL of hempseed oil, 2 L of PEG, and 1000 mL of 5% sugar brine. The Boston Bowel Preparation Scale was considered the primary outcome measure. We evaluated the interval between consumption of bowel preparation and first bowel movement. Secondary indicators included the time of cecal intubation, detection rate of polyps and adenomas, willingness to repeat the same bowel preparation, whether the protocol was tolerated, and whether there were adverse reactions during bowel preparation and were evaluated after counting the total number of bowel movements. DISCUSSION: This study aimed to test the hypothesis that hemp seed oil (30 mL) increases the quality of bowel preparation and reduces the amount of PEG. Previously, we found that its combination with 5% sugar brine can reduce the occurrence of adverse reactions. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2200057626. Prospectively registered on March 15, 2022.
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Neoplasias Colorretais , Açúcares , Idoso , Pessoa de Meia-Idade , Humanos , Polietilenoglicóis/efeitos adversos , Ceco , Estudos Prospectivos , Colonoscopia , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: Elderly rheumatoid arthritis (ERA) population faces multiple treatment dilemma. Here we aim to investigate if Gancao Nourishing-Yin decoction (GCNY) added to methotrexate (MTX) exhibit better effects in an ERA mice model. METHODS: ERA mice model was established by adding D-galactose (Dgal) to collagen-induced arthritis (CIA) mice. The model was then assigned into control group (CIA + Dgal), MTX treatment group (MTX), GCNY treatment group (GCNY), and integrative treatment group (MTX + GCNY). Pathological scoring was performed to evaluate the severity between the groups. Proteomic analysis was applied to investigate the secretory phenotype of the ERA mouse model and the underlying mechanism of GCNY, MTX and their combination. Representative cytokines related to proteomic results were further validated by ELISAs. RESULTS: CIA + Dgal mice showed more aggressive joints damage than the CIA mice. Besides changes in the inflammatory pathway such as Pi3k-Akt signaling pathway in both model, differential expressed proteins (DEPs) indicated metabolism-related pathways were more obvious in CIA + Dgal mice. Low-dose MTX failed to show pathological improvement in CIA + Dgal mice, while GCNY improved joints damage significantly. Besides down-regulated inflammation-related targets, GCNY-regulated DEPs (such as Apoc1 ~ 3, Grk2 and Creb3l3) were broadly enriched in metabolism-related pathways. MTX + GCNY showed the best therapeutic effect, and the DEPs enriched in a variety of inflammatory,metabolism and osteoclast differentiation signaling pathway. Notably, MTX + GCNY treatment up-regulated Dhfr, Cbr1, Shmt1 involved in folic acid biosynthesis and anti-folate resistance pathways indicated a coincidence synergic action. ELISAs confirmed CPR and Akt that elevated in CIA + Dgal mice were significantly ameliorated by treatments, and adding on GCNY elevated folic acid levels and its regulator Dhfr. CONCLUSION: Aging aggravated joints damage in CIA, which probably due to metabolic changes rather than more severe inflammation. GCNY showed significant effects in the ERA mice model especially when integrated with MTX to obtain a synergic action.
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The aim of this study was to examine the impact of Resveratrol nanoparticles on migration/invasion capacity of renal cell carcinoma (RCC) cells and its mechanism. Human RCC cells were exposed to dimethyl sulfoxide or gradient concentrations of Resveratrol nanoparticles respectively, and U0126 were also added in some experiments. We examined renal cell viability by MTT assay, and wound healing test and Transwell assays were used detect invasion and migration capability of RCC cells. We used Western blotting assay to analyze the protein levels in extracellular signal-regulated kinase (ERK) signaling. We also detected the enzymatic capacity of matrix metalloproteinase 2 (MMP-2) in cells by gelatin enzymatic profiling. Resveratrol nanoparticles treatment significantly suppressed cell viability to migrate and invade RCC cells in a dose-dependent manner. Also, notably were reduced MMP-2 activity and expression, and elevated TIMP-2 level were observed in RCC cells exposed with Resveratrol nanoparticles. Further, Resveratrol nanoparticles treatment significantly decreased only the expression of p-ERK1/2, but not p-p38 and p-JNK. Moreover, U0126, which is the ERK inhibitor, exerted similar role as Resveratrol nanoparticles did. Of note was that, combined use of U0126 and Resveratrol nanoparticles displayed a more intense suppression of MMP-2 activity and expression, and also the viability to migrate and invade the RCC cells, compared with Resveratrol nanoparticles treatment alone. The Resveratrol nanoparticles inhibited RCC cells migration and invasion by regulating MMP2 expression and ERK pathways.
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Carcinoma de Células Renais , Neoplasias Renais , Sistema de Sinalização das MAP Quinases , Metaloproteinase 2 da Matriz , Nanopartículas , Resveratrol , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/enzimologia , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/enzimologia , Neoplasias Renais/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/administração & dosagem , Inibidores de Metaloproteinases de Matriz/farmacologia , Nanopartículas/administração & dosagem , Invasividade Neoplásica , Resveratrol/administração & dosagem , Resveratrol/farmacologiaRESUMO
PURPOSE: Using a rat model of hyperinsulinemia, the present study investigated the role of p-ERK1/2 in benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: Forty male Sprague-Dawley rats were randomly selected and assigned to four groups: high fat diet (HFD)+BPH (n=10), HFD (n=10), BPH (n=10), and control (n=10) groups. Hyperinsulinemia was induced by HFD feeding, while BPH was induced using testosterone propionate. Plasma glucose, plasma insulin and bodyweight were examined weekly. Immunohistochemistry (IHC) and western blot analysis were used to analyze the expression of ERK1/2 and p-ERK1/2 in rat prostates. RESULTS: Plasma glucose and plasma insulin levels were significantly greater in the HFD+BPH and HFD groups, when compared to the other two groups (P<0.05). Prostate weights were significantly greater in the HFD+BPH, HFD and BPH groups, than in the control group (P<0.05). IHC and western blot analysis revealed that p-ERK1/2 expression was greater in the HFD+BPH group than in the other three groups (P<0.05). CONCLUSION: Androgens plus a hyperinsulinemic condition induced by HFD can result in prostatic cell hyperplasia, and this mechanism may be correlated to the upregulation of p-ERK1/2. Further investigations of this possibility are required.
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Hiperinsulinismo/complicações , Sistema de Sinalização das MAP Quinases/fisiologia , Hiperplasia Prostática/complicações , Animais , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Invasive mechanical ventilation (IMV) is associated with the development of adverse pulmonary and non-pulmonary outcomes in very premature infants. Various modes of non-invasive respiratory support are increasingly being used to decrease the incidence of bronchopulmonary dysplasia. The aim of this trial is to compare the effect of non-invasive high-frequency oscillatory ventilation (NHFOV) and nasal continuous positive airway pressure (NCPAP) in preterm infants with respiratory distress syndrome (RDS) as a primary non-invasive ventilation support mode. METHODS/DESIGN: In this multi-center randomized controlled trial, 300 preterm infants born at a gestational age of 266/7 to 336/7 weeks with a diagnosis of RDS will be randomized to NHFOV or NCPAP as a primary mode of non-invasive respiratory support. The study will be conducted in 18 tertiary neonatal intensive care units in China. The primary outcome is the need for IMV during the first 7 days after enrollment in preterm infants randomized to the two groups. The prespecified secondary outcomes include days of hospitalization, days on non-invasive respiratory support, days on IMV, days on supplemental oxygen, mortality, need for a surfactant, severe retinopathy of prematurity requiring laser treatment or surgery, patent ductus arteriosus needing ligation, bronchopulmonary dysplasia, abdominal distention, air leak syndromes, intraventricular hemorrhage (≥ grade 3), spontaneous intestinal perforation, necrotizing enterocolitis (≥II stage), and nasal trauma. Other secondary outcomes include Bayley Scales of Infant Development at 18-24 months of corrected age. DISCUSSION: In recent decades, several observational studies have compared the effects of NHFOV and NCPAP in neonates as a rescue mode or during weaning from IMV. To our knowledge, this will be the first multi-center prospective, randomized controlled trial to evaluate NHFOV as a primary mode in preterm infants with RDS in China or any other part of the world. Our trial may help to establish guidelines for NHFOV in preterm infants with RDS to minimize the need for IMV, and to decrease the significant pulmonary and non-pulmonary morbidities associated with IMV. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03099694 . Registered on 4 April 2017.
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Pressão Positiva Contínua nas Vias Aéreas , Recém-Nascido Prematuro , Ventilação não Invasiva/métodos , Nascimento Prematuro , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Fatores Etários , Desenvolvimento Infantil , China , Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Multicêntricos como Assunto , Ventilação não Invasiva/efeitos adversos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologia , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: The aim of this study was to compare the effect of noninvasive high-frequency oscillatory ventilation (nHFOV) with nasal continuous positive airway pressure (nCPAP) in preterm infants with moderate-severe respiratory distress syndrome (RDS) after surfactant administration via INSURE (intubation, surfactant, extubation) method on the need for invasive mechanical ventilation (IMV). METHODS: A total of 81 infants with a gestational age (GA) of 28-34 weeks were eligible and were randomized to nCPAP (n = 42) or to nHFOV (n = 39). The need for IMV was the primary outcome. The incidence of bronchopulmonary dysplasia (BPD), occurrence of intraventricular hemorrhage (IVH), and air leaks, and mortality were considered as secondary outcomes. RESULT: A total 76 infants finally completed the study. The need for IMV was significantlylower in the nHFOV group compared with the nCPAP group(24.3% vs 56.4%, P < 0.01). The incidence of IVH, air leaks or BPD was similar between the two groups. In addition, the mortality rate was not statistically different. CONCLUSION: In this prospective, randomized controlled study, nHFOV significantly reduced the need for IMV as compared with nCPAP in preterm infants with moderate-severe RDS without increase in adverse effects.
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Respiração Artificial/métodos , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Displasia Broncopulmonar/etiologia , Hemorragia Cerebral Intraventricular/etiologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Surfactantes Pulmonares/uso terapêutico , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológicoRESUMO
BACKGROUND: Urinary stones are common medical disorders and the treatment of impacted proximal ureteral stones (IPUS) is still a challenge for urologists. The aim of this study was to compare the efficacy and safety of minimally invasive percutaneous nephrolithotomy (MI-PCNL) and ureteroscopic lithotripsy (URL) in the treatment of IPUS via a meta-analysis. METHODS: We collected studies using PubMed, Embase, and Cochrane Library from 1978 to November 2016 and analyzed them using Stata 12.0 and RevMan 5.3. Odds ratios (ORs) and standard mean difference (SMD) were calculated for binary and continuous variables respectively, accompanied with 95% confidence intervals (CIs). All study procedures followed the PRISMA guidelines. RESULTS: Five prospective studies were included in our meta-analysis, with 242 MI-PCNL and 256 URL cases. MI-PCNL was associated with a longer postoperative hospital stay than URL (SMD, 3.14; 95% CI, 1.27 to 5.55). However, no significant difference was observed in operative time (SMD, -0.38; 95% CI, -3.15 to 2.38). In addition, MI-PCNL had higher initial (OR, 11.12; 95% CI, 5.56 to 22.24) and overall stone-free rates (OR, 8.70; 95% CI, 3.23 to 23.45) than URL, along with lower possibilities of surgical conversion (OR, 0.11; 95% CI, 0.03 to 0.49) and postoperative shock wave lithotripsy (OR, 0.06; 95% CI, 0.02 to 0.18). Regarding complications, no significant differences were observed between MI-PCNL and URL (OR, 1.39; 95% CI, 0.93 to 2.10), except for hematuria (OR, 4.80; 95% CI, 1.45 to 15.94). CONCLUSIONS: MI-PCNL is optimal and should be considered as the preferred treatment method for IPUS, as it has better efficacy and a safety profile similar to that of URL. However, further high quality studies with larger sample size are required in future.
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Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Nefrostomia Percutânea/métodos , Cálculos Ureterais/cirurgia , Humanos , Resultado do TratamentoRESUMO
We compared the efficacy of contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT) for the diagnosis of renal cystic lesions via a meta-analysis to determine the value of CEUS in the prediction of the malignant potential of complex renal cysts. Eleven studies were evaluated: 4 control studies related to CEUS and CECT, 3 studies related to CEUS and 4 studies related to CECT. According to the random effects model, the pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio for CEUS/CECT were 0.95/0.90, 0.79/0.85, 4.39/5.00, and 0.10/0.15, respectively. The areas under the summary receiver operating characteristic (AUCs-SROC) curves for the two methods were 94.24% and 93.39%, and the estimated Q values were 0.8805 and 0.8698, respectively. Comparing the Q index values of CEUS and CECT revealed no significant difference between the two methods (P>0.05). When compared with conventional CECT, CEUS is also useful for diagnosing renal cystic lesions in the clinic.
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Neoplasias Renais/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Meios de Contraste/uso terapêutico , HumanosRESUMO
OBJECTIVE: To identify the parental origin of methyl-CpG-binding protein 2 (MECP2) gene mutations in Chinese patients with Rett syndrome. METHODS: Single nucleotide polymorphisms (SNPs) in intron 3 of the MECP2 gene were analyzed by PCR and sequencing in 115 patients with Rett syndrome. Then sequencing of the SNP region was performed for the fathers of the patients who had at least one SNP, to determine which allele was from the father. Then allele-specific PCR was performed and the products were sequenced to see whether the allele from father or mother harbored the mutation. RESULTS: Seventy-six of the 115 patients had at least one SNP. Three hot SNPs were found in these patients. They were: IVS3+22C >G, IVS3+266C >T and IVS3+683C>T. Among the 76 cases, 73 had a paternal origin of MECP2 mutations, and the other 3 had a maternal origin. There were multiple types of MECP2 mutation of the paternal origin, including 4 frame shift, 2 deletion and 67 point (56C >T, 6C >G, 2A >G, 2G >T and 1A >T) mutations. The mutation types of the 3 patients with maternal origin included 2 frame shift and 1 point (C >T) mutation. CONCLUSION: In Chinese RTT patients, the MECP2 mutations are mostly of paternal origin.
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Proteína 2 de Ligação a Metil-CpG/genética , Mutação/genética , Pais , Síndrome de Rett/genética , Sequência de Bases , Pré-Escolar , Análise Mutacional de DNA , Pai , Feminino , Humanos , Masculino , Mães , Polimorfismo de Nucleotídeo ÚnicoRESUMO
OBJECTIVE: Rett syndrome (RTT) is a neurodevelopmental disorder occurring almost exclusively in females as sporadic cases due to de novo mutations in the methyl-CpG-binding protein 2 gene (MECP2). Familial cases of RTT are rare and are due to X-chromosomal inheritance from a carrier mother. Recently, DNA mutations in the MECP2 have been detected in approximately 84.7% of patients with RTT in China. To explain the sex-limited expression of RTT, it has been suggested that de novo X-linked mutations occur exclusively in male germ cells resulting therefore only in affected daughters. To test this hypothesis, we have analyzed the parental origin of mutations and the XCI status in 15 sporadic cases with RTT due to MECP2 molecular defects. METHODS: Allele-specific PCR was performed to amplify a fragment including the position of the mutation. The allele-specific PCR products were sequenced to determine which haplotype contained the mutation. It was then possible to determine the parent of origin by genotyping the single nucleotide polymorphism (SNP) in the parents. The degree of XCI and its direction relative to the X chromosome parent of origin were measured in DNA prepared from peripheral blood leucocytes by analyzing CAG repeat polymorphism in the androgen receptor gene (AR). RESULTS: Except for 2 cases who had a frameshift mutation; all the remaining 13 cases had a C-->T transition mutation. Paternal origin has been determined in all cases with the C-->T transition mutation. For the two frameshift mutations, paternal origin has been determined in one case and maternal origin in the other. The frequency of male germ-line transmission in mutations is 93.3%. Except for 2 cases who were homozygotic at the AR locus, of the remaining 13 cases, 8 cases had a random XCI pattern; the other five cases had a skewed XCI pattern and they favor expression of the maternal origin allele. CONCLUSION: De novo mutations in sporadic RTT occur almost exclusively on the paternally derived X chromosome and that this is most probably the cause for the high female: male ratio observed in sporadic cases with RTT. Random XCI was the main XCI pattern in sporadic RTT patients. The priority inactive X chromosome was mainly of paternal origin.
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Proteína 2 de Ligação a Metil-CpG/genética , Síndrome de Rett/genética , Inativação do Cromossomo X , Aberrações Cromossômicas , Cromossomos Humanos X , Feminino , Humanos , Masculino , Mutação , Polimorfismo de Nucleotídeo ÚnicoRESUMO
OBJECTIVE: Rett syndrome (RTT) is a neurodevelopmental disorder that represents one of the most common genetic causes of mental retardation in girls. The aim of this study was to investigate the correlation between MECP2 genotype and phenotype and thereby not only to provide assistance for clinical care, but also facilitate clinical genetic counseling. METHOD: Individual phenotype characteristic and clinical severity of 126 children with RTT diagnosed by molecular genetic methods were evaluated by using scales of Kerr et al and Scala et al. Statistical package SPSS 12.0 was used for analyses of data. Since the majority of the data were not normally distributed, non-parametric tests were used. The Kruskal-Wallis test/Wilcoxon Mann-Whitney test was employed to compare total severity phenotype scores. The Fisher exact test was used for comparing rates. Statistical significance was set at P < 0.05. RESULT: There were no significant differences in the average overall scores for RTT patients with mutations in the region of methyl-CpG-binding domain (MBD) compared with those mutations in the transcription repression domain (TRD) and C terminal segment (CTS), also patients with nonsense mutations compared with missense mutations, frameshift mutations and large deletions (P > 0.05). The RTT patients with nonsense mutations located in the region of MBD have more severe phenotype than those with missense mutations in the same region (P = 0.016). Among p.T158M, p.R168X, c.806delG and p.R255X, there were no significant differences in the average overall scores (P > 0.05), but there were significant differences in language skill (P = 0.028) and in language impairment rate at different level (P = 0.019). CONCLUSION: There are relationships between MECP2 genotype and phenotype:the RTT patients with nonsense mutations located in MBD tend to develop more severe phenotype;there are significant differences in language skill and language impairment rate in the groups with p.T158M, p.R168X, c.806del and p.R255X, which had higher frequency in children below five-years of age and the p.R168X present with most severe impairment.
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Proteína 2 de Ligação a Metil-CpG/genética , Síndrome de Rett/genética , Adolescente , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , FenótipoRESUMO
OBJECTIVE: To study the spectrum of mutations in methyl-CpG-binding protein 2 gene (MECP2) and cyclin-dependent kinase-like 5 gene (CDKL5) in Chinese pediatric patients with Rett syndrome (RTT), and establish a simple, quick, and efficient gene test method as well as screen a strategy of genetic diagnosis for RTT. METHODS: Genomic DNA was extracted using standard procedures from the peripheral blood leukocytes of 117 pediatric patients diagnosed from 1987 to 2007. PCR was used to amplify the exons 1 - 4 of MECP2 using published primers. If no mutation was identified after screening exons 2 - 4, exon 1 was screened. If no mutation was identified in MECP2 by sequencing, multiplex ligation dependent probe amplification (MLPA) was employed to screen for large deletions by using P015C kit. If no mutation was identified in the MECP2 by sequencing and MLPA respectively, then the coding region of CDKL5 was screened by denaturing high performance liquid chromatography (DHPLC). RESULTS: The total mutation frequency in MECP2 and CDKL5 genes among all RTT patients was 82%. MECP2 mutations were found in 86% (137/159) of the patients with classical RTT and in 44% (8/18) of those with atypical RTT. Most of the mutations were missense mutations, accounting for 39%, followed in order of frequency by nonsense mutations 28%, frame shift mutations 17% and large deletions 14.5%. The eight most frequent MECP2 mutations were p.T158M (13%), p.R168X (12%), c.806delG (7%), p.R255X (6%), p.R270X (5%), p.R133C (5%), p.R306C (4%), and p.R106W (3%), with p.T158M as the most common of the MECP2 mutations and c.806delG as a hotspot mutation in Chinese patients with RTT. Only one synonymous mutation was identified in CDKL5. CONCLUSION: The spectrum of MECP2 mutations within the mainland Chinese RTT patients is similar to that of those patients reported in the world. p.T158M, p.R168X, c.806delG, p.R255X, p.R270X, p.R133C, p.R306C, and p.R106W are the hotspot mutations of MECP2 and c.806delG is a specific hotspot mutation in Chinese patients with RTT. The most effective method to screen mutations is to screen the exon 4. MLPA is an effective supplement to the routine methods.