Comparison and evaluation of experimental mediastinitis models: precolonized foreign body implants and bacterial suspension inoculation seems promising

Background  

Post-sternotomy mediastinitis (PSM) is a devastating surgical complication affecting 1–3% of patients that undergo cardiac surgery. Staphylococcus aureus is one of the most commonly encountered bacterial pathogen cultured from mediastinal samples obtained from patients with PSM. A component of the membrane of the gram positive bacteria, lipoteichoic acid, stimulates the blood monocytes and macrophages to secrete cytokines, radicals and nitrogen species leading to oxido-inflammatory damage. This seems to be responsible for the high mortality rate in PSM. For the evaluation of the pathogenesis of infection or for the investigation of alternative treatment models in infection, no standard model of mediastinitis seems to be available. In this study, we evaluated four mediastinitis models in rats.     

Aortic valve calcification: its significance and limitation as a marker for coronary artery disease

Aortic valve calcification (AVC) is correlated with atherosclerotic risk factors; however, its significance remains largely unknown. The aim of this study was to investigate whether AVC detected by transthoracic echocardiography can be a useful marker for the identification of significant coronary artery disease (CAD), particularly in elderly patients. The study included 432 consecutive patients with suspected CAD who were admitted for the first time for coronary angiography. Two-dimensional transthoracic echocardiography and selective coronary angiography were performed in all patients. Aortic valve calcification was defined as bright dense echoes of > 1 mm on one or more cusps and decreased mobility of the involved cusp. Aortic valve calcification was detected in 64 of the 337 patients with significant CAD, but only in 9 of 95 cases with normal or mildly stenotic coronary arteries (19% vs 9%, p < 0.001). The severity of coronary artery disease (defined as the number of obstructed vessels) was not related to the presence of AVC (p > 0.05). Stepwise multiple logistic regression analysis of the study patients revealed only age (p=0.003, odds ratio= 1.56) and AVC (p<0.001, odds ratio = 2.03) as independent predictors of CAD. When the study population was divided into two groups as those below (n = 338) and above (n = 94) 75 years old, AVC failed to be a predictor of CAD in those >75 years old (p > 0.05, odds ratio = 0.8) while it remained the most significant predictor of CAD (p<0.001, odds ratio=2.19 in patients aged <75 years. In conclusion, detection of AVC by transthoracic echocardiography may be a useful noninvasive marker for identification of significant CAD in patients younger than 75 years old. Its clinical usefulness is limited in elderly patients.     

Prevention of Pulmonary Complications of Pneumoperitoneum in Rats

Background  

Carbon dioxide (CO₂) pneumoperitoneum facilitates the visualization of abdominal organs during laparoscopic surgery. However, the associated increase in intra-abdominal pressure causes oxidative stress, which contributes to tissue injury.     

Psychological effects of tibolone and sequential estrogen-progestogen therapy in perimenopausal women.

OBJECTIVE: To investigate changes in psychological symptoms before and after continuous tibolone treatment and sequential estrogen-progestogen therapy in perimenopausal women. METHODS: In this prospective, randomized, controlled study, perimenopausal women were randomly allocated to treatment with either tibolone 2.5 mg/day for 28 days (n = 28), or 0.625 mg conjugated equine estrogens (CEE) for 25 days plus 5 mg medroxyprogesterone acetate (MPA) daily on days 16-25 (n = 33). The differences in Beck's depression scores and serum lipid profiles before and after 1 year of treatment with both regimens were compared. RESULTS: Both groups were similar with respect to demographic characteristics. The differences in Beck's depression scores before and after treatment were statistically significant in the tibolone group (21.3 vs 17.1, p = 0.038) and also in the group receiving standard sequential estrogen-progestogen treatment (15.7 vs. 13.0, p = 0.040). In the sequential estrogen-progesterone group, a statistically significant increase was measured in high-density lipoprotein (HDL)-cholesterol levels after treatment (49.1 vs. 56.8 mg/dl, p = 0.023). CONCLUSION: Tibolone is as effective as sequential estrogen-progesterone therapy in alleviating the psychological symptoms of the perimenopause. In addition, CEE + MPA induces favorable changes in HDL-cholesterol.     

The relation between impaired glucose tolerance and slow coronary flow

BACKGROUND: Impaired glucose tolerance is a preliminary stage in the development of type 2 diabetes mellitus and has been shown to increase the risk of cardiovascular morbidity and mortality in addition to causing endothelial dysfunction. In this study, we sought to determine if impaired glucose tolerance is related to slow coronary flow, an angiographic phenomenon caused by coronary micro and macrovascular endothelial dysfunction. METHODS: The population of this prospective study consisted of 28 patients with documented slow coronary flow, defined according to TIMI frame count method, [20 (71.4%) males; 51+/-9 years] and 30 patients with normal coronary flow [17 (56.6%) males; 47+/-6 years]. All study patients underwent an oral glucose tolerance test after 12 h of fasting. Lipid profile, hemoglobin A1c and systemic blood pressure were measured in all patients. RESULTS: There was no difference between two groups with respect to age, fasting plasma glucose, triglyceride, total cholesterol, high density lipoprotein, low density lipoprotein, hemoglobin A1c, systolic-diastolic blood pressure levels, history of smoking and alcohol consumption. Plasma glucose at 2 h of oral glucose tolerance test was significantly higher in slow coronary flow patients compared to control group (145+/-44 vs. 112+/-38 mg/dl, P = 0.001, respectively). In addition, the number of patients who met the criteria of impaired glucose tolerance was significantly higher in slow coronary flow patient group [16 (57%) vs. 7 (23%), P = 0.002, respectively). CONCLUSIONS: Our results suggest that impaired glucose tolerance may be an independent etiological factor for slow coronary flow phenomenon.     

Impairment of flow-mediated vasodilatation of brachial artery in patients with Cushing's Syndrome

Background Cushing’s Syndrome (CS) is associated with excess and premature cardiovascular disease. Endothelial dysfunction is the initiating event in the development of atherosclerosis. Endothelial function is assessed by flow-mediated dilatation (FMD) of brachial artery. The aim of this study was to assess FMD in patients with CS. Methods We prospectively evaluated 22 patients with CS (12 women, 10 men; aged 42 ± 11 years, serum cortisol 28.2 ± 14 μg/dl, 24-h urinary free cortisol (UFC) 269 ± 92 μg/day), and 23 control subjects (13 women, 10 men; aged 43 ± 10 years, serum cortisol 14 ± 4 μg/dl, 24 h cortisol 60 ± 22 μg/day). Endothelial function, measured as FMD of the brachial artery using ultrasound, was calculated in two groups. Endothelial function was evaluated by assessing 1-min postischemic FMD of the brachial artery. Results FMD was lower in patients with CS than that in those without (11.7 ± 4.8% vs. 15.8 ± 3.2%, P = 0.0001, respectively). There was no significant difference between two groups regarding baseline diameter of brachial artery. But, hyperemia diameter was lower in patients with CS than without CS (3.6 ± 0.22 mm vs. 3.9 ± 0.19 mm, P = 0.04, respectively) Conclusion Endothelium-dependent FMD may impair in patients with CS compared to controls. Measurement of endothelial function may identify high-risk individuals early and therapy to reduce or retard endothelial dysfunction in patients with CS may lead to decreased cardiovascular morbidity and mortality.     

Contact lenses in the correction of childhood aphakia.

PURPOSE: To evaluate the results of extended-wear silicone contact lenses (Silsoft, Bausch & Lomb, Rochester, NY, U.S.A) after congenital cataract extraction. METHOD: Case records of congenital cataract extraction performed between 1992-1999, in the Department of Ophthalmology, Dokuz Eylül University School of Medicine, were retrospectively reviewed. Convenient-power extended-wear silicone contact lenses (Silsoft) were prescribed for patients 5 to 12 days after surgery. Patients were scheduled for follow-up control visits once per month in the first year, bimonthly in the second year, and quarerly visits thereafter. Visual acuity, fixation, binocularity, and deviation were checked at each follow-up visit. Examination of the cornea and the contact lens surface was also performed at each visit. RESULTS: A total of 51 children (83 eyes) were included in the study. Mean age was 19.4 +/- 18 months. Mean duration of contact lens wear per lens was 26 +/- 11 weeks. Contact lens wear was discontinued for 11 eyes: 6 because of unstable lens, frequent loss, and financial problems, and 5 were discontinued because of recurrent irritation and corneal infiltration. Mean contact lens usage time per patient was 5.8 years, and mean contact lens loss was 0.98 per year. Visual acuity improved in 58 (69.8%) eyes and remained unaltered in the remaining 25 eyes. CONCLUSION: Extended-wear silicone contact lenses offer a safe, easy treatment option for childhood aphakia, providing prolonged wearing time and low rates of complications and drop out.