Mutation analysis of NANOS3 in 80 Chinese and 88 Caucasian women with premature ovarian failure

NANOS3 encodes an RNA-binding protein and has a conserved function in germ cell development. Our objective was to investigate whether mutations in NANOS3 were present in Chinese and Caucasian women with premature ovarian failure. A known synonymous single-nucleotide polymorphism (rs 2016163) in exon 1 was identified through sequencing 80 Chinese and 88 Caucasian women with premature ovarian failure. No additional single-nucleotide polymorphisms or mutations were found in exons encoding for NANOS3. Our findings suggest that mutations in NANOS3 exons are rare in both Chinese and Caucasian women with premature ovarian failure.     

Functional iron deficiency and diastolic function in heart failure with preserved ejection fraction

Background

Functional iron deficiency (FID) is an independent risk factor for poor outcome in advanced heart failure with reduced EF, but its role in heart failure with preserved EF (HFPEF) remains unclear. We aimed to investigate the impact of FID on cardiac performance determined by pressure–volume loop analysis in HFPEF.

Methods

26 HFPEF patients who showed an increase in LV stiffness by pressure–volume (PV) loop analysis obtained by conductance-catheterization, performed exercise testing, echocardiographic examination including tissue Doppler and determination of iron metabolism: serum iron, ferritin and transferrin saturation. HFPEF patients who provided ferritin < 100 μg/l or ferritin of 100–299 μg/l in combination with transferrin saturation < 20% were defined as having FID. In 14 patients the expression of transferrin receptor was determined from available endomyocardial biopsies.

Results

Fifteen out of 26 HFPEF patients showed FID without anemia. Compared to control subjects and HFPEF patients without FID, HFPEF patients with FID showed an up-regulation of the myocardial transferrin receptor expression (p < 0.05). No differences between HFPEF patients with and without iron deficiency were found in heart dimensions, systolic and diastolic function obtained by PV-loop and echocardiography analysis. According to the linear regression analysis, LV stiffness was correlated with peak oxygen uptake (r = − 0.636, p < 0.001) but not with the ferritin level or transferrin saturation. No relation was found between FID and exercise capacity. The association of LV stiffness with exercise performance was independent from the level of iron deficiency.

Conclusion

In non-anemic HFPEF patients, cardiac dysfunction and impaired exercise capacity occur independently of FID.     

Machine learning approach for classification of ADHD adults

Machine learning techniques that combine multiple classifiers are introduced for classifying adult attention deficit hyperactivity disorder (ADHD) subtypes based on power spectra of EEG measurements. The analyzed sample includes 117 adults (67 ADHD, 50 controls). The measurements are taken for four different conditions: two resting conditions (eyes open and eyes closed) and two neuropsychological tasks (visual continuous performance test and emotional continuous performance test). We divide the sample into four data sets, one for each condition. Each data set is used for training of four different support vector machine classifiers, while the output of classifiers is combined using logical expression derived from the Karnaugh map. The results show that this approach improves the discrimination between ADHD and control groups, as well as between ADHD subtypes.     

Cardiac events after combined surgery for coronary and carotid artery disease

Objective: To evaluate serious cardiac events after combined (either single or two stage) coronary artery surgery (CAS) and carotid endarterectomy (CEA) for concomitant coronary and carotid artery disease. Methods: We have analyzed our 15 year experience (January 1981–September 1996) with 201 consecutive patients operated on using both approaches. Group A consisted of 48 patients with the single-stage procedure, while in group B (153 patients), two stage procedure was carried out, either as carotid endarterectomy (CEA), followed by coronary artery bypass surgery (CAS) (group B₁⁻ 103 patients), or as CAS followed by CEA (group B₂⁻ 50 patients). Five patients from B₁ group died after the CEA procedure, but were included, despite the fact they never reached the second stage. Left main coronary artery disease was found in 41 patients (20.4%), poor left ventricular function in 49 (24.4%) previous MI in 133 (66.2%), while 136 (67.7%) were in NYHA functional class III or IV. Bilateral carotid involvement was present in 61 patients (30.3%). Unstable angina was more prevalent in groups A and B₂ (P<0.0001), NYHA class III/IV in group A (versus B₁, P=0.001 and versus B₂, P=0.02), low ejection fraction in groups A and B₂ (P<0.0001), bilateral carotid stenosis in group B₁ (versus A, P=0.003 and versus B₂, P<0.0001), and ulcerated plaque in group B₁ (P<0.0001). These differences dictated the surgical strategy, which resulted in different protocols for clinical and operative management. Results: Early mortality for the entire group was 5.5% (11/201) 6.2% in group A, 7.8% in group B₁ and 0% in group B₂, respectively; (P>0.05). Serious morbidity occurred in 7.5% of patients (8.3% in group A, 7.8% in group B₁ and 6% in group B₂, respectively; P>0.05). Univariate analysis revealed only bilateral carotid stenosis to influence early outcome (P=0.04). Conclusion: Patients with concomitant coronary and carotid artery disease have relatively good immediate operative results, providing all existing lesions are corrected. Despite it did not reach the statistical significance, cardiac events were less frequent in groups A and B₂ indicating possible protective effect of prior CAS in patients with concomitant disease.     

Vascular calcification and atherosclerosis in hemodialysis patients: what can we learn from the routine clinical practice?

BACKGROUND: Hemodialysis (HD) patients are at increased risk for arterial intimal (AIC) and medial calcification (AMC). METHODS: In a cross-sectional study on 153 HD patients we evaluated the presence of AIC and AMC using plain radiography of the pelvis and the presence of atherosclerotic lesions using high-resolution B-mode ultrasonography of the common carotid arteries (CCA). RESULTS: The radiography of the pelvis confirmed the frequent presence of AIC (35.3%) and AMC (35.9%) in our HD patients. Arterial calcification was absent (non calcified-NC) in a minority of patients (28.8%). Patients with AIC had significantly higher prevalence of atherosclerotic plaques on CCA (78.6%) compared with both other groups and a higher number of documented atherosclerotic complications, such as cardiovascular (85.2%), cerebrovascular (33.3%) and peripheral arterial disease (38.9%) in comparison with the NC patients. According to the 1-year calculated data from patient records, there were no significant differences in the specific HD risks, such as the dose of prescribed calcium carbonate and vitamin D3, serum levels of calcium, phosphate, calcium-phosphate product and intact parathyroid hormone. All four bone metabolism markers within the range proposed by K/DOQI guidelines were achieved in 9.3%, 14.5% and 20.4% in the AIC, AMC and NC group, respectively. CONCLUSIONS: Patients with AIC and AMC are frequently found in the HD population. Screening for arterial calcifications in chronic kidney disease patients is suggested even in the early pre-dialysis period. The highest proportion of patients within the guidelines proposed range for bone and mineral metabolism markers was observed in the NC group. A longer period of data analysis is required in order to evaluate the possible role of some traditional and HD-specific risk factors for the development of arterial calcifications. The achievement of the K/DOQI guidelines is an important issue in the prevention of those conditions.     

Advantages and limitations of the autofluorescent diagnostics of the laryngeal cancer and precancerosis

Any endoscopic diagnostic procedure that is capable of giving exact information on laryngeal lesions without damaging the tissue has essential advantages over standard biopsy. Tissue autofluorescence is defined as a natural ability of tissue to fluoresce when exposed to a certain light wavelength. This feature is a consequence of the presence of fluorophores in the tissues, which are activated by a narrow wavelength range. However, due to their biochemical and biophysical characteristics, laryngeal precancerosis and cancer do not fluoresce when exposed to blue light. In the present study, we used Pentax’s System of Autofluorescent Endoscopy (SAFE 1000) to detect autofluorescence disturbances from laryngeal mucosa. Diagnostic parameters (sensitivity and specificity) of the microlaryngoscopy (MLS) and SAFE 1000 in the diagnosis of laryngeal precancerosis and carcinoma were compared and discussed. We have found that SAFE had a better sensitivity with regard to mentioned laryngeal pathology, but MLS had better specificity than SAFE. The overall diagnostic sensitivity in the diagnostics of laryngeal atypical hyperplasia and cancer with SAFE was 89%, as opposed to 73% with MLS. Diagnostic specificity of SAFE for all cases of laryngeal carcinomas and atypical hyperplasia was 78%. The specificity of MLS in diagnostics of laryngeal carcinomas cases was 98%, while that for cases of atypical hyperplasia was 100%. Many other conditions that have impact on autofluorescent features of laryngeal mucosa were also discussed.