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101.
Wlodarska EK Konka M Zaleska T Ploski R Cedro K Pucilowska B Bekiesinska-Figatowska M Rydlewska-Sadowska W Ruzyllo W Hoffman P 《International journal of cardiology》2005,105(2):126-133
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inheritant disease with an autosomal dominant mode of transmission with incomplete penetrance and variable expression. Linkage analysis in affected families succeeds in identifying 9 loci determining 9 subtypes of the disease. Genotype phenotype correlation is unclear and the influence of various environmental factors is discussed. OBJECTIVES: Genotype phenotype correlation in 2 pairs of monozygotic twins with ARVC and the role of environmental factors are analyzed. PATIENTS AND METHODS: Among 40 pts with ARVC and their 195 relatives there were 2 pairs of monozygotic twins: brothers, age 47 y; and sisters, age 48 y. History, ECG, Holter monitoring, 2D and Doppler Echo, and MRI were analyzed. RESULTS: Twin brothers: ARVC was diagnosed in the proband after the episode of VT with LBBB morphology (enlarged right ventricle, focal hypokinesia of apex, MR evidence of adipose tissue in RV wall). Identical morphology of RV was seen in asymptomatic twin brother. The patient presenting arrhythmia has been rowing for 4 years. Twin sisters: diagnosis was done during family screening. Both were asymptomatic. RV morphology typical for ARVC was found discrete in one of them (bulges adipose tissue in the RV apex); the latter showed changes suggesting RV abnormality (mild segmental dilatation of infundibulum, adipose tissue in a free wall of the RV). No differences in previous viral infections and sports involvement were observed. CONCLUSIONS: 1. Clinical picture of ARVC in monozygotic twins is not identical. 2. Strenuous effort may be a factor triggering the arrhythmia in pts with ARVC. 相似文献
102.
There are many places on the earth, where natural background radiation exposures are elevated significantly above about 2.5 mSv/year. The studies of health effects on populations living in such places are crucially important for understanding the impact of low doses of ionizing radiation. This article critically reviews some recent representative literature that addresses the likelihood of radiation-induced cancer and early childhood death in regions with high natural background radiation. The comparative and Bayesian analysis of the published data shows that the linear no-threshold hypothesis does not likely explain the results of these recent studies, whereas they favor the model of threshold or hormesis. Neither cancers nor early childhood deaths positively correlate with dose rates in regions with elevated natural background radiation. 相似文献
103.
Szyguła-Jurkiewicz B Wilczek K Szafron B Przybylski R Chudzik B Osuch M Zebala M Poloński L 《Polskie Archiwum Medycyny Wewn?trznej》2004,112(2):911-918
Acute coronary syndromes (ACS) without persistent ST-segment elevation are the main cause of hospitalization, morbidity and mortality. The objective of this study was to compare clinical and angiographic parameters as well as in-hospital results of treating 307 consecutive patients with ACS without persistent ST-segment elevation with either PCI or CABG. Inclusion criteria were: rest angina within the last 24 hours, ST-segment depression (> 0.5 mm), T-wave inversion (> 1 mm) in at least two leads, positive serum cardiac markers. PCI was performed in 75.9% of patients and 24.1% of patients underwent CABG. Both groups did not differ as to age, sex, history of diabetes, arterial hypertension, heart failure, smoking and ejection fraction. Positive troponin was significantly more frequent in the PCI group. 51% of PCI patients and 80% of CABG patients had complete revascularization (p = 0.00001). Independent predictors of in-hospital death in the CABG group were: inability to determine culprit vessel during coronary angiography due to lesions' severity (OR 13.65; 95% CI 9.40-15.20; p = 0.007) and heart failure (OR 15.58; 95% CI 12.29-18.01; p = 0.003). In the PCI group these independent predictors were: Braunwald's IIIC unstable angina (OR 5.48; 95% CI 3.10-7.17; p = 0.04) and diabetes (OR 2.22; 95% CI 1.07-3.90; p = 0.003). In-hospital mortality rate was significantly higher in the CABG group (8.1% vs 1.7% p < 0.01). Patients with multivessel coronary artery disease and ACS without ST-segment elevation treated with PCI have better in-hospital outcome than patients assigned to CABG, but the rate of complete revascularization is lower. 相似文献
104.
Deciphering principles of morphogenesis from temporal and spatial patterns on the integument
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Ang Li Yung‐Chih Lai Seth Figueroa Tian Yang Randall B. Widelitz Krzysztof Kobielak Qing Nie Cheng Ming Chuong 《Developmental dynamics》2015,244(8):905-920
Background : How tissue patterns form in development and regeneration is a fundamental issue remaining to be fully understood. The integument often forms repetitive units in space (periodic patterning) and time (cyclic renewal), such as feathers and hairs. Integument patterns are visible and experimentally manipulatable, helping us reveal pattern formative processes. Variability is seen in regional phenotypic specificities and temporal cycling at different physiological stages. Results: Here we show some cellular/molecular bases revealed by analyzing integument patterns. (1) Localized cellular activity (proliferation, rearrangement, apoptosis, differentiation) transforms prototypic organ primordia into specific shapes. Combinatorial positioning of different localized activity zones generates diverse and complex organ forms. (2) Competitive equilibrium between activators and inhibitors regulates stem cells through cyclic quiescence and activation. Conclusions: Dynamic interactions between stem cells and their adjacent niche regulate regenerative behavior, modulated by multi‐layers of macro‐environmental factors (dermis, body hormone status, and external environment). Genomics studies may reveal how positional information of localized cellular activity is stored. In vivo skin imaging and lineage tracing unveils new insights into stem cell plasticity. Principles of self‐assembly obtained from the integumentary organ model can be applied to help restore damaged patterns during regenerative wound healing and for tissue engineering to rebuild tissues. Developmental Dynamics 244:905–920, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
105.
106.
AIM
Drugs used for postoperative nausea and vomiting prophylaxis are believed to provoke torsadogenic changes in cardiac repolarization. The aim of this study was to assess the effect of small doses of droperidol on the parameters of cardiac repolarization, including the QTc interval and transmural dispersion of repolarization.METHODS
A total of 75 patients were randomly allocated to receive 0.625 or 1.25 mg droperidol or 8 mg ondansetron. The QTc interval was calculated using Bazett''s formula and the Framingham correction. The transmural dispersion of repolarization was determined as Tpeak–Tend time.RESULTS
Transient QT prolongation, corrected with both formulae, followed 1.25 mg of droperidol 10 min after administration. No change in the QTc value was observed in the other groups. When corrected with Bazett''s formula, QTc was prolonged above 480 ms in two patients receiving 1.25 mg droperidol (at the 10th and 20th minute of the study) and in one receiving ondansetron. No patients developed a QTcB prolongation over 500 ms. No increase above 480 ms was observed relative to the Framingham correction method. There were no significant differences in the Tpeak–Tend time either between or within the groups.CONCLUSION
In men without cardiovascular disorders small doses (1.25 mg) of droperidol prophylaxis induced transient QTc prolongation without changes in transmural dispersion of repolarization. The apparently low risk of the drug applies only in low risk male patients with a low pro-QTc score. 相似文献107.
Pieniazek P Kabłak-Ziembicka A Pasowicz M Przewłocki T Zmudka K Moczulski Z Tracz W 《Kardiologia polska》2002,57(10):322-30; discussion 331
Carotid artery stenosis is one of the main causes of stroke. Nowadays two techniques for treating carotid stenosis are available - surgical endarterectomy and percutaneous angioplasty combined with stent implantation at the site of stenosis. Cerebral protection devices during internal carotid stenting significantly decrease the incidence of periprocedural complications, however, during the introduction of protective devices the cerebral blood flow remains unprotected. Therefore, the quest for a system specifically protecting cerebral flow during the whole procedure is still underway. Temporary reversal of carotid flow during the procedure using the Parodi Anti-Emboli System seems a viable solution. The present study describes the first two patients who underwent internal carotid artery stenting using this technique in our institution. 相似文献
108.
Straburzyńska-Migaj E Ochotny R Wachowiak-Baszyńska A Straburzyńska-Lupa A Leśniewska K Wiktorowicz K Cieśliński A 《Kardiologia polska》2005,63(5):478-85; discussion 486-7
INTRODUCTION: Heart rate variability (HRV) analysis is a non-invasive method of assessment of the autonomic nervous system's effects on heart function. In chronic heart failure (CHF), decreased HRV correlates with the progression of the disease. It is also known that in CHF increased levels of proinflammatory cytokines are present. Because these molecules are believed to influence the nervous system at both the central and peripheral levels, their potential role in HRV reduction in the course of CHF has been proposed. AIM: The study was designed to verify potential relations between cytokines and HRV parameters in CHF patients. The concept of the study was driven by the recognition of controversies in this field and the paucity of published reports. METHODS: Forty-four patients with CHF and stable NYHA class I-IV symptoms and 15 healthy controls were enrolled in the study. Time-domain HRV analysis was performed based on of 24-hour Holter ECG monitoring. Plasma concentrations of soluble TNFalpha receptors sTNF-RI and sTNF-RII and interleukin 6 (IL-6) were measured using commercially available ELISA kits (Quantikine, RD Systems). RESULTS: In patients with CHF, HRV indices included in the analysis were significantly decreased, and the levels of cytokines increased in comparison with the control group. In the whole study population, both in the CHF patients and the control group, significant negative correlations were observed between sTNF-RI level and long-term HRV indices such as SDNN (r=-0.44; p=0.0006), SDANN (r=-0.44; p=0.0005) and short-time index SDNNI (r=-0.37; p=0.004). Similar negative correlations were found between sTNF-RII level and SDNN (r=-0.35; p=0.007), SDANN (r=-0.34; p=0.01), and SDNNI (r=-0.31; p=0.02), as well as between IL-6 level and SDNN (r=-0.41; p=0.001), SDANN (r=-0.44; p=0.0005) and SDNNI (r=-0.34; p=0.009). CONCLUSIONS: Significant negative correlations between TNF-alpha soluble receptors sTNF-RI, sTNF-RII and IL-6 levels and time-domain HRV parameters were observed in the study. Because the results of investigations conducted so far do not elucidate the cause-effect relationship, further studies are needed to clarify the mechanisms of HRV depression in CHF and the role of cytokines in this severe clinical condition. 相似文献
109.
Przybylski G Jarzemska A Czerniak J Siemiatkowska K Gadzińska A Cieśliński K 《Polskie Archiwum Medycyny Wewn?trznej》2008,118(3):143-147
Dermatomyositis (DM) is a connective tissue disease characterized by specific inflammatory lesions in muscle biopsy. It is caused by vasculitis determined by humoral factors with subsequent inflammatory cell accumulation, mainly T CD4+ and B cells, which infiltrate myocytes leading to its vacuolization and degeneration (mainly in the skeletal muscles, rarely in the smooth muscles). The incidence of DM is estimated at 1-10 per million in adults and at 1-3.2 per million in children. The autoimmune mechanism of disease induction is not fully recognized. Several lines of evidence showed the link between DM and neoplastic disease. The first report of dermatomyositis associated with stomach cancer, by Stertz, comes from 1916. In the same time, Kankeleit reported DM associated with breast cancer. Presumably, it is the result of immune reaction against antigens common for muscle and neoplastic cells or some paraneoplastic syndrome underlying mechanism. The report presents the case of a 52-year-old woman with DM (diagnosed according to the Bohan and Peter criteria) and with coexistent squamous lung cancer in situ. The left upper lobectomy was performed. No complications in postoperative period were observed. During more than 2 years of follow-up after the surgery, the patient remained in good condition, without DM symptoms, or cancer relapse. Considering that DM may be associated with lung cancer; extensive diagnostic work-up to exclude neoplastic lesions should be performed. Patients aged 40 years or more should be particularly screened. 相似文献
110.
Obstructive sleep apnea and hypertension 总被引:4,自引:0,他引:4
There is growing evidence of a causal relationship between obstructive sleep apnea (OSA) and hypertension. Untreated OSA may
have direct and deleterious effects on cardiovascular function and structure through several mechanisms, including sympathetic
activation, oxidative stress, inflammation, and endothelial dysfunction. OSA may contribute to or augment elevated blood pressure
levels in a large proportion of the hypertensive patient population. It is important to consider OSA in the differential diagnosis
of hypertensive patients who are obese. OSA should be especially considered in those hypertensive patients who respond poorly
to combination therapy with antihypertensive medications. 相似文献