Plesiomonas shigelloides pneumonia

Plesiomonas shigelloides is known to cause mild to cholera-like diarrhea in most infected persons. In immunocompromised patients extra-intestinal manifestations have been described. We report the first case of pneumonia caused by P. shigelloides in a 76-year-old woman who had undergone a curative gastrectomy and esophageal-jejunostomy due to a low differentiated adenocarcinoma of the stomach (pT2, pN1 pMx, G3, R0, Lauren: intestinal type). The patient was admitted in hospital with clinical signs of pulmonary infection. CT-scan revealed a cavernous lesion in the right upper pulmonary lobe. Bronchial lavage showed a granulocytic inflammation 105CFU/ml P. shigelloides. Although antibiotic treatment led to a decrease of inflammation parameters and decrease of the pulmonary infiltrate the patient died due to development of torsades de pointes tachycardia leading to ventricular fibrillation and hypoxic brain damage.

Intravenous injection of siRNA directed against hypoxia-inducible factors prolongs survival in a Lewis lung carcinoma cancer model

Different routes for the in vivo administration of synthetic siRNA complexes targeting lung tumors were compared, and siRNA complexes were administered for the inhibition of hypoxia-inducible factor (HIF-1alpha and HIF-2alpha). Intravenous jugular vein injection of siRNA proved to be the most effective means of targeting lung tumor tissue in the Lewis lung carcinoma (LLC1) model. In comparison, intraperitoneal injection of siRNA was not suitable for targeting of lung tumor and intratracheal administration of siRNA exclusively targeted macrophages. Inhibition of HIF-1alpha and HIF-2alpha by siRNA injected intravenously was validated by immunohistofluorescent analysis for glucose-transporter-1 (GLUT-1), a well-established HIF target protein. The GLUT-1 signal was strongly attenuated in the lung tumors of mice treated with siRNA-targeting HIF-1alpha and HIF-2alpha, compared with mice treated with control siRNA. Interestingly, injection of siRNA directed against HIF-1alpha and HIF-2alpha into LLC1 lung tumor-bearing mice resulted in prolonged survival. Immunohistological analysis of the lung tumors from mice treated with siRNA directed against HIF-1alpha and HIF-2alpha displayed reduced proliferation, angiogenesis and apoptosis, cellular responses, which are known to be affected by HIF. In conclusion, intravenous jugular vein injection of siRNA strongly targets the lung tumor and is effective in gene inhibition as demonstrated for HIF-1alpha and HIF-2alpha.

Creation of ventricular septal defects on the beating heart in a new pig model

BACKGROUND/AIMS

So far, surgical and interventional therapies for muscular ventricular septal defects (mVSDs) beyond the moderator band have had their limitations. Thus, alternative therapeutic strategies should be developed. We present a new animal model for the evaluation of such strategies.

METHODS

In a pig model (n = 9), anterolateral thoracotomy was performed for exposure of the left ventricle. mVSDs were created under two- and three-dimensional echocardiography with a 7.5-mm sharp punch instrument, which was forwarded via a left ventricular puncture without extracorporeal circulation.

RESULTS

Creation of mVSDs was successful in all animals (n = 9) confirmed by echocardiography, hemodynamic measurements and autopsy. The defects were located in the midmuscular (n = 4), apical (n = 1), inlet (n = 2) and anterior part (n = 2) of the muscular septum. All animals were hemodynamically stable for further procedures. The diameter and shunt volume of the mVSDs were 4.8-7.3 mm (mean: 5.9 mm) and 12.9-41.3% (mean: 22.1%), respectively. Autopsy confirmed in all animals the creation of a substantial defect.

CONCLUSION

The described new technique for creation of an mVSD on the beating heart in a pig model is suitable for the evaluation of new therapeutic strategies for mVSD closure.