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21.
Background: RB1 gene screening aids clinical management and genetic counselling in retinoblastoma families. Here we present epigenetic changes identified during routine molecular RB1 screening of tumor and blood samples. Complications in interpreting RB1 methylation are discussed.

Materials and Methods: Screening for RB1 promoter hypermethylation was carried out by Methylation Specific PCR (MS-PCR) after bisulphite modification of DNA. The cohort consisted of 315 tumors, and 204 blood samples, from 497 retinoblastoma patients (22 patients had both blood and tumor screened).

Results: 11.4% of retinoblastoma tumors had promoter hypermethylation. It was not routinely detected in blood samples, or in tumors with two other oncogenic RB1 changes. One blood sample had promoter hypermethylation due to an X;13 translocation. One tumor had low level methylation as well as two other oncogenic changes. Histopathological analysis of a small subset of age-matched tumors was similar regardless of promoter hypermethylation status.

Conclusions: Promoter hypermethylation was detected in 11.4% of the retinoblastoma tumors and should be tested for in routine RB1 screening programmes. Constitutional samples are not expected to display RB1 hypermethylation. In a small proportion of cases it may not be possible to use this somatic change in patient management.  相似文献   
22.
Conclusion: A significant association was found of oropharyngeal tularemia with SLC11A1 allele polymorphism (INT4?G/C) and MBL2 C?+?4T (P/Q). These results indicate C allele and Q allele might be a risk factor for the development of oropharyngeal tularemia.

Aim: This study aimed to investigate the relationship of SLC11A1, MBL, and P2X7 gene polymorphism with oropharyngeal tularemia.

Methods: The study included totally 120 patients who were diagnosed with oropharyngeal tularemia. Frequencies of polymorphisms in the following genes were analyzed both in the patient and control groups in the study: SLC11A1 (5’(GT)n Allele 2/3, Int4?G/C, 3’ UTR, D543N G/A), MBL (MBL2 C?+?4T (P/Q), and P2X7 (?762 C/T and 1513 A/C).

Results: Among all polymorphisms that were investigated in this study, SLC11A1 gene showed a significance in the distriburtion of polymorphism allelle frequency at the INT4 region. Frequency of C allele was 54 (28%) in patients with oropharyngeal tularemia, and 31 (13%) in the control group (p?=?0.006 and OR = 1.96 (1.21–3.20)). An association was detected between MBL2 C?+?4T (P/Q) gene polymorphism and oropharyngeal tularemia (p?7 (?762 C/T and 1513 A/C) gene polymorphism and oropharyngeal tularemia in this study (p?>?0.05).  相似文献   
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24.
Our aim was to investigate, in patients with heart failure, the relationship between left atrial size and exercise capacity and cardiovascular events. Seventy-five patients (67 men and 8 women; mean age, 53.4 +/- 8.8 yr) with left ventricular ejection fractions of < or =0.45 (New York Heart Association functional classes I-III) were matched by age and sex with 20 healthy control subjects. Echocardiographic examinations were performed, as was exercise testing by the modified Bruce protocol. Patients were monitored for a period of 330 to 480 days for cardiac death or for heart failure that required hospitalization. The indexed left atrial diastolic size (beta level = -0.534, P <0.001) and left ventricular late diastolic filling velocity (beta level = 0.247, P <0.017) were the most important values in predicting low exercise capacity. The only independent predictor of low exercise capacity (<5 METS) was the indexed left atrial diastolic size (odds ratio, 1.428; 95% confidence interval, 1.09-1.702; P <0.001). Every 1 mm/m2 increase in indexed left atrial diastolic dimension caused a 42.8% increase in the risk of severe heart failure (exercise capacity, <5 METS). Independent predictors for cardiovascular events were indexed as left atrial systolic size (odds ratio, 1.383; 95% confidence interval, 1.145-1.671; P <0.001) and left ventricular early diastolic/late diastolic filling velocity (odds ratio, 1.096; 95% confidence interval, 1.010-1.189; P <0.027). Indexed left atrial diastolic and left atrial systolic size predict exercise capacity and cardiovascular events, respectively, in New York Heart Association functional class I through III heart failure patients.  相似文献   
25.
Measles virus (MV) constitutes a principal cause of worldwide mortality, accounting for almost 1 million deaths annually. Although a live-attenuated vaccine protects against MV, vaccination efficiency of young infants is low because of interference by maternal antibodies. Parental concerns about vaccination safety further contribute to waning herd immunity in developed countries, resulting in recent MV outbreaks. The development of novel antivirals that close the vaccination gap in infants and silence viral outbreaks is thus highly desirable. We previously identified a microdomain in the MV fusion protein (F protein) that is structurally conserved in the paramyxovirus family and constitutes a promising target site for rationally designed antivirals. Here we report the template-based development of a small-molecule MV inhibitor, providing proof-of-concept for our approach. This lead compound specifically inhibits fusion and spread of live MV and MV glycoprotein-induced membrane fusion. The inhibitor induces negligible cytotoxicity and does not interfere with receptor binding or F protein biosynthesis or transport but prevents F protein-induced lipid mixing. Mutations in the postulated target site alter viral sensitivity to inhibition. In silico docking of the compound in this microdomain suggests a binding model that is experimentally corroborated by a structure-activity analysis of the compound and the inhibition profile of mutated F proteins. A second-generation compound designed on the basis of the interaction model shows a 200-fold increase in antiviral activity, creating the basis for novel MV therapeutics. This template-based design approach for MV may be applicable to other clinically relevant members of the paramyxovirus family.  相似文献   
26.
BackgroundNon-dipper blood pressure is defined by less than a 10% reduction in nighttime blood pressure, and it is associated with cardiovascular disease. Inflammation is thought to play a role in the pathogenesis of both chronic obstructive pulmonary disease (COPD) and non-dipper blood pressure pattern, and both diseases are associated with lower quality of life.ObjectiveThe aim of this study was to investigate the effects of non-dipper blood pressure pattern in patients with COPD.MethodsA cross-sectional study was carried out with 142 patients with COPD. The Saint George Respiratory Questionnaire and the Euro Quality of Life Scale were used to collect data. To understand arterial stiffness, the augmentation index and pulse wave velocity were measured, and 24-hour ambulatory blood pressure monitoring was subsequently performed. A multivariable logistic regression model was used to understand the relationship between different independent variables and blood pressure pattern. P values lower than 0.05 were considered statistically significant.ResultsAs a result, 76.1% (n = 108) of the patients had non-dipper blood pressure pattern. Non-dipper patients had higher C-reactive protein (OR:1.123; 95% CI:1.016;1.242), augmentation index (OR: 1.057; 95% CI: 1.011;1.105) and Saint George Respiratory Questionnaire total score (OR: 1.021; 95% CI: 1.001;1.042) than dipper patients. Also, as the number of people living at home increased, non-dipper blood pressure pattern was found to be more frequent (OR: 1.339; 95% CI: 1.009;1.777).ConclusionNon-dipper blood pressure pattern may increase cardiovascular risk by triggering inflammation and may adversely affect the prognosis of COPD by lowering the disease-related quality of life. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)  相似文献   
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28.

Aim

Willis-Ekbom disease (RLS/WED) is common in chronic obstructive pulmonary disease (COPD). Patients with RLS/WED have poorer quality of sleep and more fatigue and depressive symptoms. The prevalence of RLS/WED in patients with COPD has been reported to vary between 29.1 and 36.8 %. However, during exacerbation, the prevalence can increase up to 54 %. These rates are higher than those seen in general population. We have not enough knowledge regarding the association between RLS and COPD. In this study, we aimed to determine the frequency of RLS in patients with stable COPD without comorbid conditions. In addition, we also aimed to determine possible related causative factors.

Method

We included 80 COPD patients without comorbid conditions who presented to our outpatient clinic between April 2013 and September 2013 for RLS/WED evaluation. Three cases that have polyneuropathy and one case that refused undergoing electromyography (EMG) examination were excluded from the study. Demographic data, P-A chest X-rays, pulmonary function tests (PFT), biochemical parameters (including hemogram), and dyspnea scales were evaluated for each patient. In addition, the RLS/WED rating scale and Epworth Sleep Scale (ESS) were applied. Further, each patient diagnosed with RLS/WED underwent a detailed neurological examination (performed by a neurologist) and an EMG examination to rule out polyneuropathy.

Results

Out of 76 COPD cases included in our study, 26.3 % (n?=?20) were diagnosed with RLS/WED (mean age 60.4?±?7.5 years, 20 males). The cases with RLS/WED had significantly lower body mass index (BMI) than cases without RLS/WED (p?=?0.009). There were no significant differences between cases with and without RLS/WED with respect to PFT, dyspnea scales, and arterial blood gas values. However, ESS was significantly different (p?=?0.016). There were no significant differences in RLS/WED scores and mean hs-CRP levels between COPD stages (p?=?0.424; p?=?0.518, respectively), while ESS was significantly different (p?=?0.016). ESS was significantly higher in stage B COPD than in stages A and D (p?=?0.005, p?=?0.008, respectively). Based on our model, we found that exacerbations and iron binding capacity (UIBC) were predictive factors for RLS/WED (p?<?0.100)

Conclusion

RLS/WED is a common disease in cases with stable COPD. Despite our hypothesis suggesting that the prevalence of RLS/WED in COPD is related with systemic inflammation, we did not find a significant association between hs-CRP and COPD cases with RLS/WED. However, we did find that UIBC is a predictive factor for the development of RLS/WED. Nonetheless, further studies are needed to understand the relationships between UIBC, low BMI, and the development of RLS/WED in COPD.
  相似文献   
29.
The aim of this study is to report clinical and imaging findings, and treatment outcomes of a patient with nodular posterior scleritis. A 41-year-old woman was diagnosed as nodular posterior scleritis in the light of clinical and imaging findings. At first admission best corrected visual acuity was 20/50 in her right eye. Fundus examination revealed an amelanotic subretinal mass under the superior temporal arcade associated with subretinal fluid surrounding it. B-scan ultrasonography, optical coherence tomography, fluorescein angiography, and indocyanine green angiography findings confirmed the diagnosis. As treatment, nepafenac eye drops 3 times a day, and flurbiprofen tablet 100 mg twice a day were prescribed. After 4 weeks of treatment, the ocular pain was relieved, BCVA improved to 20/20, and subretinal mass totally regressed. Although the diagnosis of nodular posterior scleritis may be confusing, it has to be kept in mind in patients with a subretinal/choroidal mass. Multimodal fundus imaging may be helpful in differential diagnosis. The condition is usually curable with non-steroidal anti-inflammatory drugs and/or systemic steroids.  相似文献   
30.

AIM

To investigate the association of serum glucocorticoid kinase gene-1 (SGK-1) DNA variants with chronic central serous chorioretinopathy (CSC).

METHODS

We enrolled 32 eyes of 32 patients who were diagnosed with chronic CSC and composed 32 normal eyes as a control group. Peripheral blood was used for DNA extraction and polymerase chain reaction (PCR) amplification. SGK1 gene was sequenced by using BigDye® Terminator v3.1 cycle sequencing KIT (Applied Biosystems, Foster City, CA, USA). The SGK1 gene and its variants were investigated in CSC patient group and control group.

RESULTS

We identified a new polymorphism M32V in two person in the patient group (Minor allele frequency (MAF)=0.009) on the region of 1-60 amino acids. The rs1057293 was located in the encoder region of the SGK 1 gene but not associated with CSC (P=0.68). An intrinsic rs1743966 is also not associated (P=0.28).

CONCLUSIONS

The new polymorphism M32V is located on the region of 1-60 amino acids which is necessary for localization to the mitochondria in CSC patient. This mutation is probably important for the energy metabolism and plays an important role in the cellular response to hyperosmotic stress and other stress stimuli. Both rs1057293 and rs1743966 are not associated with CSC.  相似文献   
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