Polymorphism of ZuBeCa3 microsatellite and its association with mammary tumor in dogs

A study was conducted to explore the genetic polymorphism at ZuBeCa3 microsatellite and to estimate the association between microsatellite polymorphism and mammary cancer in dogs. Three genotypes namely AA, AB and BB were observed both in dogs affected by mammary cancer and in non-affected dogs. In the affected group, the frequency of genotype and allele was 0.63 for AA, 0.25 for AB and 0.12 for BB genotype, and 0.76 for A and 0.24 for B allele. In the nonaffected group, the frequency of AA, AB and BB genotype was 0.39, 0.38 and 0.23 and the frequency of A and B allele was 0.58 and 0.42, respectively. Histopathological observation classified the cancer-affected animals into three groups namely, malignant solid mammary carcinoma, malignant papillary adenocarcinoma and benign papillary adenoma in which the frequency of A allele was relatively more predominant in benign tumor group, which is more than 80%. Statistical tests showed significant differences (P < 0.01) of allelic distribution between tumor-affected and non-affected group, which reveals the effect of polymorphism on occurrences of mammary cancer in dogs. Besides, chi(2) test also reflected the significant effect of genotypes on occurrences of three groups of mammary cancer in dogs.     

Early postnatal exposure to allergen and ozone leads to hyperinnervation of the pulmonary epithelium

Airway injury in infant monkeys exposed to ozone and/or house dust mite allergen (HDMA) is associated with a loss of epithelial innervation. In this study, we evaluated for persistence/recovery of the altered epithelial innervation. Thirty-day-old rhesus monkeys were exposed to repeated episodes of HDMA and/or ozone from 1 to 6 months of age and subsequently allowed to recover for 6 months in the absence of further ozone exposure and/or minimal HDMA challenge (sufficient to maintain allergen sensitization). At 1 year of age, nerve density in intrapulmonary airways was immunohistochemically evaluated using antibodies directed against protein gene product 9.5. Hyperinnervation and irregular epithelial nerve distribution was observed in both HDMA- and ozone-exposed groups; most prominent alterations were observed in animals exposed to HDMA plus ozone. Therefore, while adaptive mechanisms exist that re-establish epithelial innervation following cessation or diminution of exposure to HDMA and/or ozone, the recovery is associated with persistent proliferative mechanisms that result in hyperinnervation of the airways.     

Sirolimus causes relaxation of human vascular smooth muscle: a novel action of sirolimus mediated via ATP-sensitive potassium channels

Little is known about the vasomotor effects of sirolimus, and preliminary studies using animal models have provided conflicting results. The present study was designed to determine the effects of sirolimus on vasomotor tone in human blood vessels. Human radial artery segments were cut into rings, denuded of endothelium, and placed into organ chambers for isometric tension recording. Sirolimus (10(-10) to 10(-6) M) caused concentration-dependent relaxation of human arteries contracted with U46619 (9,11-dideoxy-11alpha,9alpha-epoxymethano-prostaglandin F(2alpha); 10(-8) M) [-log (M) EC(50) (pD(2)) = 7.28 +/- 0.1; E(max) = 57 +/- 6%] or phenylephrine (10(-6) M) (pD(2) = 7.16 +/- 0.4; E(max) = 45 +/- 9%). Sirolimus-induced relaxation was unaffected by treatment with indomethacin (10(-5) M) but was nearly abolished in tissues contracted by depolarization with elevated K(+) (60 mM). In U46619-contracted rings, the response to sirolimus was markedly inhibited in the presence of the specific ATP-sensitive potassium (K(ATP)) channel blocker, glyburide (10(-6) M), but was unaffected by treatment with blockers of large conductance, calcium-activated potassium channel (iberiotoxin, 10(-7) M), small conductance, calcium-activated potassium channel (apamin, 10(-6) M), or voltage-gated potassium channel (4-aminopyridine, 10(-3) M). The K(ATP) channel opener, aprikalim (10(-7) to 10(-5) M), caused concentration-dependent relaxations that were inhibited by glyburide (10(-6) M) and abolished in tissues contracted with elevated K(+) (60 mM), thus confirming that K(ATP) channel opening causes relaxation of these arteries. These data suggest that sirolimus, at concentrations attained in vivo, causes relaxation of human arteries, and this effect is mediated by opening of K(ATP) channels in vascular smooth muscle. Reduced vasomotor tone is a heretofore unrecognized action of sirolimus that could potentially contribute to its efficacy in drug-eluting stents.     

Experimental evaluation of safety and efficacy of plasma-treated poly-ε-caprolactone membrane as a substitute for human amniotic membrane in treating corneal epithelial defects in rabbit eyes

Purpose:To evaluate biocompatibility and safety of plasma-treated poly-ε-caprolactone (pPCL) membrane compared to the human amniotic membrane in the healing of corneal epithelial defects in an experimental model.Methods:This is a prospective, randomized animal study including 12 rabbits. Circular epithelial injury measuring 6 mm in diameter was induced over the central cornea of one eye in twelve rabbits. The rabbits were randomized into two groups; in group A, the defect was covered with human amniotic membrane, while in group B, an artificial membrane made of bio-polymer plasma-treated poly-ε-caprolactone was grafted. Six rabbits were euthanized after 1 month and the other six after 3 months and the corneal epithelium was evaluated histopathologically and with immunohistochemistry.Results:Light microscopy of the corneal tissue performed after 1 month and 3 months demonstrated similar findings with no significant complications in either group. Immunohistochemistry with anti-CK-3 antibody showed characteristic corneal phenotype in the healed epithelium. In eyes grafted with pPCL membrane, epithelial healing as estimated by a decrease in size of the defect was significantly better than the group treated with the human amniotic membrane at all time periods monitored (P < 0.05), except day 1 (P = 0.83). The percentage reduction in the size of the epithelial defect was also significantly more in the pPCL membrane group as compared to the human amniotic membrane at all time periods (P < 0.05 at all observations) post-implantation except day 1 (P = 0.73).Conclusion:Plasma-treated poly-ε-caprolactone membrane is safe, biocompatible, and effective in the healing of corneal epithelial defects in rabbits.     

Aortic debranching for descending thoracic aortic aneurysm repair by stent grafts

Endovascular repair of a descending thoracic aortic aneurysm may result in covering the ostia of the left carotid or left subclavian artery for proper proximal landing zones, and the celiac artery or superior mesenteric artery ostia in the abdomen for distal landing zones. To prevent possible complications of occluding the ostia of these vessels, the authors performed an innominate to left common carotid and left subclavian artery bypass as the first procedure in one patient. In the second patient they performed an aortoceliac and aortomesenteric bypass before stent graft placement. The stent graft repair of the descending thoracic aortic aneurysm was performed subsequently in both patients. This aortic debranching provides subsequent proper placement of thoracic stent grafts.