Clinical and angiographic features of large left main coronary artery aneurysms

Coronary artery aneurysms are defined as coronary dilatations which exceed the diameter of normal adjacent segments by 1.5 times. Left main coronary artery (LMCA) is the least frequently involved artery with a prevalence of 0.1%. Majority of coronary artery aneurysms are atherosclerotic in origin. Their size and clinical presentation is variable. A number of complications have been reported to occur during the course of the disease including thrombosis and distal embolization, myocardial ischemia and/or infarction, dissection, vasospasm, calcification, fistulization and very rarely rupture. Large aneurysms of LMCA represent a potentially fatal condition even without concomitant atherosclerotic coronary disease. Because of rarity of coronary artery aneurysms, it is difficult to standardize treatment. In this article, we presented 4 cases of large LMCA aneurysms with various clinical and angiographic features.     

Effects of vitamin K in postmenopausal women: Mini review

Possible benefits of vitamin K on bone health, fracture risk, markers of bone formation and resorption, cardiovascular health, and cancer risk in postmenopausal women have been investigated for over three decades; yet there is no clear evidence-based universal recommendation for its use.     

Biaxial flexural strength and phase transformation of Ce-TZP/Al2O3 and Y-TZP core materials after thermocycling and mechanical loading

PURPOSE

The purpose of the present study was to evaluate the effect of thermocycling and mechanical loading on the biaxial flexural strength and the phase transformation of one Ce-TZP/Al₂O₃ and two Y-TZP core materials.

MATERIALS AND METHODS

Thirty disc-shaped specimens were obtained from each material. The specimens were randomly divided into three groups (control, thermocycled, and mechanically loaded). Thermocycling was subjected in distilled water for 10000 cycles. Mechanical loading was subjected with 200 N loads at a frequency of 2 Hz for 100000 times. The mean biaxial flexural strength and phase transformation of the specimens were tested. The Weibull modulus, characteristic strength, 10%, 5% and 1% probabilities of failure were calculated using the biaxial flexural strength data.

RESULTS

The characteristic strengths of Ce-TZP/Al₂O₃ specimens were significantly higher in all groups compared with the other tested materials (P<.001). Statistical results of X-ray diffraction showed that thermocycling and mechanical loading did not affect the monoclinic phase content of the materials. According to Raman spectroscopy results, at the same point and the same material, mechanical loading significantly affected the phase fraction of all materials (P<.05).

CONCLUSION

It was concluded that thermocycling and mechanical loading did not show negative effect on the mean biaxial strength of the tested materials.     

Epidemiology of COVID-19: What changed in one year?

A coronavirus brought the first pandemic attack of this century as a flu virus did a hundred years ago. This greatest pandemic of the century brings us new opportunities to understand and explore the dynamics of a contagious disease. Nearly two years later, we are still collecting the evidence to understand the disease. Some basic epidemiological properties are still urgently needed. Not only the origin of the virus but also Ro value, possible transmission routes, epidemiologic curves, case fatality rates, seasonality, severity and mortality risk factor, effects on the risk groups, differences between countries and so on still require strong evidence prior to making final suggestions. In this review, we tried to evaluate the epidemiological evidence to scrutinize where exactly we are in this pandemic.     

Fat-Secreted Ceramides Regulate Vascular Redox State and Influence Outcomes in Patients With Cardiovascular Disease

BackgroundObesity is associated with increased cardiovascular risk; however, the potential role of dysregulations in the adipose tissue (AT) metabolome is unknown.ObjectivesThe aim of this study was to explore the role of dysregulation in the AT metabolome on vascular redox signaling and cardiovascular outcomes.MethodsA screen was conducted for metabolites differentially secreted by thoracic AT (ThAT) and subcutaneous AT in obese patients with atherosclerosis (n = 48), and these metabolites were then linked with dysregulated vascular redox signaling in 633 patients undergoing coronary bypass surgery. The underlying mechanisms were explored in human aortic endothelial cells, and their clinical value was tested against hard clinical endpoints.ResultsBecause ThAT volume was associated significantly with arterial oxidative stress, there were significant differences in sphingolipid secretion between ThAT and subcutaneous AT, with C16:0-ceramide and derivatives being the most abundant species released within adipocyte-derived extracellular vesicles. High ThAT sphingolipid secretion was significantly associated with reduced endothelial nitric oxide bioavailability and increased superoxide generated in human vessels. Circulating C16:0-ceramide correlated positively with ThAT ceramides, dysregulated vascular redox signaling, and increased systemic inflammation in 633 patients with atherosclerosis. Exogenous C16:0-ceramide directly increased superoxide via tetrahydrobiopterin-mediated endothelial nitric oxide synthase uncoupling and dysregulated protein phosphatase 2 in human aortic endothelial cells. High plasma C16:0-ceramide and its glycosylated derivative were independently related with increased risk for cardiac mortality (adjusted hazard ratios: 1.394; 95% confidence interval: 1.030 to 1.886; p = 0.031 for C16:0-ceramide and 1.595; 95% confidence interval: 1.042 to 2.442; p = 0.032 for C16:0-glycosylceramide per 1 SD). In a randomized controlled clinical trial, 1-year treatment of obese patients with the glucagon-like peptide-1 analog liraglutide suppressed plasma C16:0-ceramide and C16:0-glycosylceramide changes compared with control subjects.ConclusionsThese results demonstrate for the first time in humans that AT-derived ceramides are modifiable regulators of vascular redox state in obesity, with a direct impact on cardiac mortality in advanced atherosclerosis. (The Interaction Between Appetite Hormones; NCT02094183)     

Diagnostic Value of Magnetic Resonance Imaging in Gynaecology

In this study 23 patients with various gynaecological pathologies were evaluated. Ultrasonography and magnetic resonance imaging were performed in all cases, but only 14 were evaluated with computed tomography. On the basis of ultrasonography, 4 patients were labelled as having malignant ovarian tumours, however, this diagnosis was confirmed by magnetic resonance imaging in only 1 of the 4. Magnetic resonance imaging also determined the correct diagnosis in a patient with endometrioma whereas computed tomography showed only a simple cyst, and ultrasonography diagnosed a subserous myoma. Tumour was demonstrated by magnetic resonance imaging in 2 patients with cervical carcinoma although computed tomography and ultrasonography had previously shown no tumour mass in these patients. It was concluded that magnetic resonance imaging is much superior to computed tomography and ultrasonography in gynaecological diagnosis. This advantage results from the correct detection of the contents of ovarian cysts, the number and localization of uterine leiomyomas in T2 scans, invasion of uterine malignancies and differential diagnosis of subserous uterine leiomyomas from ovarian tumours.     

Situs inversus and coronary artery disease

Situs inversus is a rare condition and there are few reports of myocardial revascularization in such patients. A 56-year-old woman with situs inversus totalis and coronary artery disease underwent successful anastomosis of the right internal mammary artery to the anterior descending coronary artery, and a saphenous vein graft to the right coronary artery.     

Video-assisted extracorporeal appendectomy

BACKGROUND: Despite many randomized controlled trials, there are still several important doubts about laparoscopic appendectomy. Longer operative time and greater cost are the two major disadvantages of the laparoscopic technique. PATIENTS AND METHODS: In current techniques of laparoscopic appendectomy, the appendix is ligated and divided within the abdominal cavity. We have performed 423 laparoscopic appendectomies using an extracorporeal technique during the last 8 years. In this technique, the appendix is delivered to the surface through the cannula, and appendectomy is carried out extracorporally. RESULTS AND CONCLUSION: The extracorporeal technique of appendix removal can be performed as safely and efficiently as the open technique. We report our data on the series of 423 operations, in which we had the encouraging experience that the video-assisted extracorporeal technique is a practical and reasonable alternative to the traditional laparoscopic technique.