Characterization of Methicillin-resistant Staphylococcus aureus isolated from public surfaces on a university campus, student homes and local community.

AIM: Isolation and characterization of methicillin-resistant Staphylococcus aureus (MRSA) from frequently touched nonhospital environmental surfaces at a large university, student homes and community sites. METHODS AND RESULTS: Twenty-four isolates from 21 (4·1%, n = 509) surfaces were MRSA positive and included 14 (58%, n = 24) SCCmec type IV, two (8%, n = 24) type I, and eight (33%, n = 24) were not type I-IV (NT). Six different multilocus sequencing types were identified by PCR and sequencing. PCR assays identified one (4·2%, n = 24) Panton-Valentine leukocidin (PVL) positive, 22 (92%, n = 24) arginine catabolic mobile element (ACME) positive and 23 (96%, n = 24) multidrug-resistant (kanamycin, macrolide, tetracycline) MRSA isolates. Eleven (46%, n = 24) USA300 isolates were determined by pulsed-field gel electrophoresis. CONCLUSION: The MRSA-positive environmental surfaces were identified in student homes (11·8%, n = 85), the community (2·3%, n = 130) and the university (2·7%, n = 294). USA300 strains were isolated from the university, student homes and community samples. This is the first report of the animal clone ST97 on urban environmental surfaces. SIGNIFICANCE AND IMPACT OF THE STUDY: The study highlights the distribution of USA300 on frequently touched surfaces. Whether contact with these MRSA contaminated environmental surfaces are associated with increased risk of transmission of MRSA to people needs further research.

Genetic variation in the pro-melanin-concentrating hormone gene affects carcass traits in Bos taurus cattle.

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 ATG start codon (g.-134A>T). The alleles at this SNP were significantly associated with average fat and grade fat in two crossbred populations of Bos taurus cattle. The g.-134T allele may introduce a binding site for the transcriptional repressor, adenovirus E4 promoter binding protein, which may contribute to this effect. The g.-134A allele occurred in 67% of cattle examined and was associated with higher fat levels.

State-coordinated services for traumatic brain injury survivors: toward a model delivery system.

Since 1985, the state of Minnesota, through a variety of advocacy, legislative, and interagency efforts, has made incremental gains in public policy and service development for persons with traumatic brain injury (TBI). This article reviews the roles and functions of select state programs and departments in coordinating TBI services. Key initiatives, as well as the current model of public policy and services, are outlined. Current and future service development and initiatives are discussed. Finally, specific implementation recommendations are proposed.

Fibronectin biosynthesis and cell-surface expression by cardiac and non-cardiac endothelial cells.

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 endogenous radiolabeling, we found that all cell types except aortic valve endothelial cells synthesized and released into the culture media substantial quantities of fibronectin. Using radioiodination of intact cells, we found that, whereas both thoracic aorta and pulmonary artery cells had measurable fibronectin on the surface, aortic valve, mitral valve, and coronary artery cells had little cell-surface fibronectin present. Immunocytochemical staining showed that all endothelial regions except aortic valve had substantial quantities of immunoreactive fibronectin in vivo. These data suggest that the aortic valve endothelium may be distinct from other endothelia. Such differences could be important for the pathogenesis of valvular disease.

Perioperative blood transfusion and determinants of survival after liver resection for metastatic colorectal carcinoma.

The authors reviewed their institutional experience with liver resection for metastatic colorectal carcinoma to (1) determine whether perioperative blood transfusion affects survival; (2) identify prognostic determinants; and (3) estimate the patient requirement for a prospective randomized trial designed to demonstrate efficacy of liver resection. Two hundred eighty consecutive patients treated by potentially curative liver resection between 1960 and 1987 were included. Data were obtained for all but 10 patients for at least 5 years after operation or through 1990. Actuarial survival curves related to potential prognostic determinants were analyzed with the log-rank test. Overall, survival was 47 +/- 3% at 3 years and 25 +/- 3% at 5 years, including 4% 60-day operative mortality rate. Eighty-one patients who did not receive blood 7 days before to 14 days after operation had 60 +/- 6% 3-year and 32 +/- 6% 5-year survival compared with 40 +/- 4% and 21 +/- 3% survival rates for 183 patients who received at least one unit (p = 0.03, operative deaths excluded). Extrahepatic disease (p = 0.015), extrahepatic lymph node involvement (p = 0.002), satellite configuration of multiple metastases (p = 0.0052), and initial detection by abnormal liver enzymes (p = 0.0005) were associated with poor survival rates. Synchronous presentation of metastatic and stage B primary disease was associated with a favorable prognosis (p = 0.003). The requirement for a prospective randomized trial estimated by an exponential survival model would be 36, 74, 168, or 428 patients if 5-year survival without resection were 1, 5, 10, or 15%. We conclude that (1) perioperative blood transfusion may be adversely associated with survival; (2) extrahepatic disease, extrahepatic lymph node involvement, satellite configuration, and initial detection by clinical examination or a liver enzyme abnormality portend a poor prognosis; and (3) a prospective randomized trial of liver resection is impractical because of the large patient requirement, at least by a single institution.

Platelet adherence to cardiac and noncardiac endothelial cells in culture: lack of a prostacyclin effect.

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 and ascending aorta. We found that valvular endothelial cells showed a twofold to threefold higher adherence than ascending aortic endothelial cells of chromium 51-labeled platelets in the presence of proteolytically active thrombin. This finding did not correlate with endothelial prostacyclin release: cardiac valve endothelial cells released more prostacyclin than did, ascending aortic cells, exogenous prostacyclin had no effect on thrombin-stimulated adherence, and aspirin inhibition of endothelial prostacyclin synthesis showed no effect on platelet adherence. Fixation of platelets abolished thrombin-stimulated adherence; fixation of endothelial cells had minimal effect. We suggest that these differences may contribute to the propensity of the cardiac valve to develop nonbacterial thrombotic endocarditis.

Glycoproteins synthesized by cultured cardiac valve endothelial cells: unique absence of fibronectin production.

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 from the ascending thoracic aorta. The cells were endogenously radiolabeled and extracted with detergent. Glycoproteins in the cell extracts were then isolated on wheat germ lectin-agarose and compared using autoradiography following polyacrylamide gel electrophoresis. Fibronectin was identified by immunoblotting with specific antibody. The results showed that the outstanding difference between the endothelial cell types was the virtual absence of fibronectin in the cardiac valve endothelial cell extract.

Effect of cholecystokinin on pancreatic carcinogenesis in the hamster model.

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 similarly except that both CCK (20 IDU/kg body wt) and BOP (2.5 mg/kg body wt) were given weekly for 20 weeks. The results showed that CCK in the first experiment (single BOP dose) inhibited pancreatic cancer induction in a statistically significant fashion when given either 3 h prior to (P less than 0.05) or simultaneously with BOP (P less than 0.0005); however, CCK, when administered after BOP did not alter the cancer incidence as compared with hamsters treated with BOP alone. In the second experiment (chronic BOP treatment) the pattern and the incidence of pancreatic tumors were not affected by CCK.

Porcine cardiac valvular subendothelial cells in culture: cell isolation and growth characteristics.

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 ridges and piles similar to vascular smooth muscle cells. Endogenous in vitro labeling experiments using 35S-methionine showed that valve subendothelial cells synthesized and released several proteins not observed in parallel experiments using porcine skin fibroblasts and smooth muscle cells. Mitogen assays using media conditioned by porcine aortic valvular endothelial cells showed that the valve subendothelial cells, when compared to skin fibroblasts and smooth muscle cells, were particularly avid responders to the growth factors released by valve endothelial cells in vitro. The valve subendothelial cells also released 10-fold more prostacyclin in response to arachidonate than did skin fibroblasts or smooth muscle cells. We conclude that valve subendothelial cells show features that distinguish them from other cultured mesenchymal cells, and that this culture system will be useful for studies of the cellular basis of valvular heart disease.

The persistence of DNA damage in the pancreas of syrian golden hamsters treated with N-nitrosobis(2-oxopropyl)-amine.

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 persisted until 4 weeks. When higher BOP doses (20 and 40 mg/kg) were used, considerable DNA damage was still evident in the pancreas, but not in the liver at 6 weeks. Greater damage persisted in hamsters given 40 mg/kg, compared with those administered 20 mg/kg.

Induction of benign and malignant lip tumors in Syrian hamsters by topical application of N-nitrosobis(2-oxopropyl)amine and N-nitroso(2-hydroxypropyl)(2-oxopropyl)amine.

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 affected by the dose of BOP or HPOP administered. BOP is excreted unchanged and as HPOP in the saliva of Syrian hamsters injected subcutaneously with BOP and pilocarpin. This result may help to explain preliminary observations that subcutaneously injected BOP and pilocarpin also lead to lip tumors.