Acquired heart block: A possible complication of patent ductus arteriosus in a preterm infant

A large patent ductus arteriosus (PDA) is a frequently encountered clinical problem in extremely low birth weight (ELBW) infants. It leads to an increased pulmonary blood flow and in a decreased or reversed diastolic flow in the systemic circulation, resulting in complications. Here we report a possible complication of PDA not previously published. On day 8 of life, a male ELBW infant (birth weight 650 g) born at a gestational age of 23 weeks and 3 days developed an atrioventricular block (AV block). The heart rate dropped from 168/min to 90/min, and the ECG showed a Wenckebach second-degree AV block and intraventricular conduction disturbances. Echocardiography demonstrated a PDA with a large left-to-right shunt and large left atrium and left ventricle with high contractility. Within several minutes after surgical closure of the PDA, the heart rate increased, and after 30 min the AV block had improved to a 1: 1 conduction ratio. Echocardiography after 2 h revealed a significant decrease of the left ventricular and atrial dimensions. Within 12 h, the AV block completely reversed together with the intraventricular conduction disturbances. We suggest that PDA with a large left-to-right shunt and left ventricular volume overload may lead to an AV block in an ELBW infant. Surgical closure of the PDA may be indicated. Copyright (C) 2007 S. Karger AG, Basel

Use Them for What They Are Good at: Mealworms in Circular Food Systems

Future food systems must provide more food produced on less land with fewer greenhouse gas emissions if the goal is to keep planetary boundaries within safe zones. The valorisation of agricultural and industrial by-products by insects is an increasingly investigated strategy, because it can help to address resource scarcities and related environmental issues. Thus, insects for food and feed have gained increasing attention as a sustainable protein production strategy in circular food systems lately. In this article, we provide an overview on by-products, which have already been fed to T. molitor (mealworms), a common edible insect species. In addition, we investigate other by-products in Austria, which can be suitable substrates for T. molitor farming. We also provide an overview and discuss different perspectives on T. molitor and link it with the circular economy concept. We identify several future research fields, such as more comprehensive feeding trials with other by-products, feeding trials with mealworms over several generations, and the development of a standardized framework for insect rearing trials. In addition, we argue that due to their ability to convert organic by-products from agricultural and industrial processes into biomass in an efficient way, T. molitor can contribute towards resource-efficient and circular food and feed production. However, several hurdles, such as legal frameworks, need to be adapted, and further research is needed to fully reap the benefits of mealworm farming

Future Proteins: Sustainable Diets for <i>Tenebrio molitor</i> Rearing Composed of Food By-Products

Since the human population is continuously growing, sufficient food with low environmental impact is required. Especially, the challenge of providing proteins will deepen and insects can contribute to a more sustainable and efficient source of protein for human consumption. Tenebrio molitor larvae are highly nutritious and rearing mealworms is more environmentally friendly compared to the production of traditional livestock meat. To use T. molitor as a more sustainable alternative to conventional proteins, it is essential to apply diets from a local and sustainable source. Therefore, the objective of this study was to find local by-products or leftovers which can be used in mass production of larvae as a main substrate. Feeding trials investigating twenty-nine different substrates were conducted to evaluate larval growth performance and adult reproduction by determining development times, survival rates, biomass, and fecundity. Several suitable by-products were identified that can be used in high quantities as single component diet for T. molitor rearing, revealing a high survival rate, short development time, high mean total biomass, and successful breeding. The most successful substrate—malt residual pellets—was found to be an alternative to the most used substrate, wheat bran. Furthermore, corn germ meal, sweet chestnuts, bread remains, soybeans, sweet potatoes, and wheat germs have been discovered to be suitable diets for T. molitor. Moreover, the findings of this study contribute towards using several substrates as supplements

Immunohistochemical and radiological characterization of wound healing in porcine liver after radiofrequency ablation

Background: Radiofrequency ablation (RFA) is a minimal invasive therapeutic option for patients with hepatocellular carcinoma or liver metastases. We investigated RFA-induced cellular changes in the liver of pigs. Material and Methods: Healthy pigs (n=18) were sacrificed between day 0 and 3 months after RFA. The wound healing process was evaluated by computed tomography (CT), chromotrope anilinblue (CAB) staining of large-scale and standard tissue sections. Immunohistochemistry (IHC) for heat shock protein 70, Caspase-3, Ki67, Reelin, Vinculin, Vimentin and αSMA was perfomed. Results: One day after RFA, CAB staining showed cell damage and massive hyperaemia. All IHC markers were predominantly expressed at the outer borders of the lesion, except Reelin, which was mainly detected in untreated liver regions. By staining for Hsp70, the heat stress during RFA was monitored, which was most distinct 1-2 days after RFA. CT revealed decreased lesion size after one week. Development of a Vimentin and α-SMA positive fibrotic capsule was observed. Conclusion: In the early phase signs of cell damage, apoptosis and proliferation are dominant. Reduced expression of Reelin suggests a minor role of hepatic stellate cells in the RFA zone. After one week myofibroblasts become prominent and contribute to the development of the fibrotic capsule. This elucidates the pathophysiology of RFA and could contribute to the future optimization of RFA procedures