Characteristics of atherosclerotic plaque distribution in coronary artery bifurcations: an intravascular ultrasound analysis

OBJECTIVE: Vessel bifurcations are prone to atherosclerotic plaque accumulation. Using volumetric intravascular ultrasound analysis, we investigated atheroma distribution at human coronary bifurcations in vivo. METHODS: We analyzed plaque distribution in 49 left anterior descending coronary artery-diagonal and 20 left circumflex coronary artery-obtuse marginal bifurcations with <50% angiographic stenosis. Cross-sections were analyzed at 1 mm intervals in segments 5 mm proximal and distal from the bifurcation. Planimetry of the lumen and external elastic membrane (EEM) was performed and plaque thickness measured at four different points relative to the branch: 0 degrees, 90 degrees, 180 degrees and 270 degrees. EEM, lumen and plaque volume and percentage plaque burden (plaque volume/EEM volume) were calculated in the proximal and distal segments. The side-branch take-off angle was analyzed in the cross-sectional images. RESULTS: Volumetric analysis showed that EEM, lumen and plaque were larger (P<0.001) in proximal segments than distal segments, whereas percent plaque burden was similar in these segments. Plaque accumulated on the opposite wall to the flow divider. Plaque distribution tended to be more eccentric in distal segments (P=0.05) compared to proximal segments. In 26 of 69 lesions, an asymmetric side-branch take-off was found and was associated with asymmetric plaque distribution compared to those lesions that had a symmetric side-branch take-off (P<0.01). CONCLUSION: We found characteristic patterns of plaque distribution at coronary bifurcations. Proximal segments demonstrated larger plaque volume than distal segments, despite similar percentages of plaque burden. Plaque volume accumulated opposite to the flow divider, especially in distal segments. The side-branch take-off angle in the cross-sectional plane influenced the plaque distribution in bifurcation lesions.     

Evaluation of the thyroid disorders in children with familial Mediterranean fever

Clinical Rheumatology - Although it is well-known that autoimmune thyroid diseases are more common in most of the autoimmune connective tissue diseases, the relationship between autoinflammatory...     

Hemoperitoneum secondary to spontaneous rupture of metastatic gastric leiomyosarcoma of the liver: Report of a case.

Hepatic rupture with resulting hemoperitoneum due to metastatic cancer is uncommon. Reports in the literature have described a wide variety of neoplasms causing this usually fatal phenomenon. We describe a rare case of spontaneous rupture of hepatic metastases from gastric leiomyosarcoma. A 72-year-old male patient with sudden onset severe epigastric pain was rushed into emergency service. After examination, the patient underwent urgent operation withe possible diagnosis of perforated gastric or duodenal ulcer. During exploration, we determined bleeding mass on the diaphragmatic side of the left lobe of the liver and a mass on the posterior wall of the stomach. Hemostasis was provided.     

Melatonin protects against gentamicin-induced nephrotoxicity in rats

Acute renal failure is a major complication of gentamicin (GEN), which is widely used in the treatment of gram-negative infections. A large body of in vitro and in vivo evidence indicates that reactive oxygen metabolites (or free radicals) are important mediators of gentamicin nephrotoxicity. In this study we investigated the role of free radicals in gentamicin-induced nephrotoxicity and whether melatonin, a potent antioxidant could prevent it. For this purpose female Sprague-Dawley rats were given intraperitoneally either gentamicin sulphate (40 mg/kg), melatonin (10 mg/kg), gentamicin plus melatonin or vehicle (control) twice daily for 14 days. The rats were decapitated on the 15th day and kidneys were removed. Blood urea nitrogen (BUN) and creatinine levels were measured in the blood and malondialdehyde (MDA) and glutathione (GSH) levels, protein oxidation (PO) and myeloperoxidase (MPO) activity were determined in the renal tissue. Gentamicin was observed to cause a severe nephrotoxicity which was evidenced by an elevation of BUN and creatinine levels. The significant decrease in GSH and increases in MDA levels, PO and MPO activity indicated that GEN-induced tissue injury was mediated through oxidative reactions. On the other hand simultaneous melatonin administration protected kidney tissue against the oxidative damage and the nephrotoxic effect caused by GEN treatment.     

Single-Center Study of 72 Patients with Severe Combined Immunodeficiency: Clinical and Laboratory Features and Outcomes

Journal of Clinical Immunology - Severe combined immunodeficiency is an inborn error of immunity characterized by impairments in the numbers and functions of T and B lymphocytes due to various...     

Melatonin ameliorates chronic renal failure-induced oxidative organ damage in rats

Chronic renal failure (CRF) is associated with oxidative stress that promotes production of reactive oxygen species (ROS). Melatonin, the chief secretory product of the pineal gland, was recently found to be a potent free radical scavenger and antioxidant. The aim of this study was to examine the role of melatonin in protecting the aorta, heart, corpus cavernosum, lung, diaphragm, and kidney tissues against oxidative damage in a rat model of CRF, which was induced by five of six nephrectomy. Male Wistar albino rats were randomly assigned to either the CRF group or the sham-operated control group, which had received saline or melatonin (10 mg/kg, i.p.) for 4 wk. CRF was evaluated by serum blood urea nitrogen (BUN) level and creatinine measurements. Aorta and corporeal tissues were used for contractility studies, or stored along with heart, lung, diaphragm, and kidney tissues for the measurement of malondialdehyde (MDA, an index of lipid peroxidation), protein carbonylation (PC, an index for protein oxidation), and glutathione (GSH) levels (a key antioxidant). Plasma MDA, PC, and GSH levels and erythrocytic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in CRF. In the CRF group, the contraction and the relaxation of aorta and corpus cavernosum samples decreased significantly compared with controls (P < 0.05-0.001). Melatonin treatment of the CRF group restored these responses. In the CRF group, there were significant increases in tissue MDA and PC levels in all tissues with marked reductions in GSH levels compared with controls (P < 0.05-0.001). In the plasma, while MDA and PC levels increased, GSH, SOD, CAT, and GSH-Px activities were reduced. Melatonin treatment reversed these effects as well. In this study, the increase in MDA and PC levels and the concomitant decrease in GSH levels of tissues and plasma and also SOD, CAT, GSH-Px activities of plasma demonstrate the role of oxidative mechanisms in CRF-induced tissue damage, and melatonin, via its free radical scavenging and antioxidant properties, ameliorates oxidative organ injury. CRF-induced dysfunction of the aorta and corpus cavernosum of rats was reversed by melatonin treatment. Thus, supplementing CRF patients with adjuvant therapy of melatonin may have some benefit.     

Effect of alpha-interferon therapy on bone marrow fibrosis in hairy cell leukemia

Iliac crest trephine biopsy specimens from 16 patients treated with recombinant alpha 2-interferon (alpha-IFN) for hairy cell leukemia (HCL) were examined for reticulin and collagen content. These data were compared with the hairy cell index (HCl), the proportion of hairy cells to the overall cellularity of the bone marrow. Specimens were studied immediately before alpha-IFN therapy, at 6-month intervals during, and in six patients 6 months after cessation of therapy. All patients presented with increased bone marrow fibrosis ranging from focally increased reticulin to a diffuse increase in both reticulin and collagen content. This fibrosis was observed to decrease during alpha- IFN therapy inasmuch as the hairy cell population was diminished in the bone marrow in 13 patients. Regression analysis of HCl v bone marrow fibrosis showed a positive correlation (r = .73, P less than .02). Six patients demonstrated a reduction in bone marrow reticulin and collagen to normal levels during alpha-IFN therapy. Two of six patients demonstrated increased bone marrow fibrosis and HCl 6 months after cessation of alpha-IFN therapy. Three of 16 patients exhibited no decrease in bone marrow reticulin content during therapy despite a decreased bone marrow hairy cell population.