Sarah Helgeson

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We established culture lines derived from the subendothelial region of the porcine aortic valve. These cells were isolated by extensive collagenase digestion of valvular tissue and were serially propagated with stable morphology. In sparse culture, valve subendothelial cells resembled skin fibroblasts. When confluent, the valve subendothelial cells formed(More)
Mammalian pro-melanin-concentrating hormone (PMCH) has previously been shown to affect feed intake in rodent species. The objectives of this study were to sequence the Bos taurus PMCH gene in order to identify any existing genetic variants and to evaluate whether these affected carcass traits. An A-to-T SNP was identified at position -134 relative to the(More)
Weekly topical application of equitoxic doses of N-nitrosobis(2-oxopropyl)amine (BOP) or N-nitroso(2-hydroxypropyl)(2-oxopropyl)amine (HPOP) to lip and/or vagina of female Syrian hamsters led to the development of papillomas and carcinomas of the lip, papillomas of the vagina, and tumors of internal organs. The relative incidence of the tumor types is(More)
We have previously reported that cultured porcine cardiac valve endothelial cells released less fibronectin into the culture supernatant when compared to other porcine endothelial cells. In this report we compared the spectrum of glycoproteins synthesized by cardiac valve endothelial cells to glycoproteins synthesized by comparison endothelial cells derived(More)
We examined the biosynthesis and surface expression of fibronectin, an adhesive glycoprotein, in several types of cultured porcine endothelial cells: pulmonary artery, thoracic aorta, coronary artery, aortic valve, and mitral valve. We used immunocytochemical staining to compare the levels of fibronectin present in these same tissues in vivo. Using(More)
Cardiac tissues show a propensity to develop nonbacterial thrombotic endocarditis, a meshwork of platelets and fibrin. This lesion may cause a predisposition to subsequent colonization by circulating microorganisms, leading to infective endocarditis. We measured platelet adherence in vitro to cultured endothelial cells derived from the porcine aortic valve(More)
Neisseria gonorrhoeae, a sexually-transmitted gram-negative bacterium, causes gonorrhoea in humans. The min genes of N. gonorrhoeae are involved in cell division site selection with oxyR co-transcribed with these genes. The mutation in min genes and oxy R cause aberrant cell morphology and aggregation patterns, respectively. Our objective was to assess the(More)
DNA damage was estimated in the liver, pancreas and salivary gland of Syrian hamsters given N-nitrosobis(2-oxopropyl)amine (BOP) by alkaline sucrose gradient centrifugation. A single BOP dose (10 mg/kg) produced in all 3 tissues extensive DNA damage that was largely repaired in the salivary gland by 4 weeks, while in the liver and pancreas, some DNA damage(More)
To examine the effect of cholecystokinin (CCK) on pancreatic carcinogenicity in the hamster model, two sets of experiments were carried out. In one study, CCK (20 IDU/kg body wt) was given 3 h before, simultaneously with or 3 h after a single dose (20 mg/kg body wt) of N-nitrosobis(2-oxopropyl)amine (BOP). In another experiment, hamsters were treated(More)
porB DNA sequence analysis and Neisseria gonorrhoeae multiantigen sequence typing (NG-MAST) methods were compared for their abilities to discriminate strains and to identify epidemiologically congruent pairs of N. gonorrhoeae. Both methods provided high-level discrimination of strains. NG-MAST further differentiated large porB-based clusters. However,(More)
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