A Comprehensive Review on the Surgical Aspect of Lung Transplant Models in Mice and Rats

Lung transplantation improves the outcome and quality of life of patients with end-stage pulmonary disease. However, the procedure is still hampered by the lack of suitable donors, the complexity of the surgery, and the risk of developing chronic lung allograft dysfunction. Over the past decades, translational experiments in animal models have led to a better understanding of physiology and immunopathology following the lung transplant procedure. Small animal models (e.g., rats and mice) are mostly used in experiments regarding immunology and pathobiology and are preferred over large animal models due to the ethical aspects, the cost-benefit balance, and the high throughput possibility. In this comprehensive review, we summarize the reported surgical techniques for lung transplantation in rodent models and the management of perioperative complications. Furthermore, we propose a guide to help identify the appropriate species for a given experiment and discuss recent experimental findings in small animal lung transplant models

Allogeneic Hematopoietic Stem Cell Transplantation After Prior Lung Transplantation for Hereditary Pulmonary Alveolar Proteinosis: A Case Report

Pulmonary alveolar proteinosis (PAP) is a rare, diffuse lung disorder characterized by surfactant accumulation in the small airways due to defective clearance by alveolar macrophages, resulting in impaired gas exchange. Whole lung lavage is the current standard of care treatment for PAP. Lung transplantation is an accepted treatment option when whole lung lavage or other experimental treatment options are ineffective, or in case of extensive pulmonary fibrosis secondary to PAP. A disadvantage of lung transplantation is recurrence of PAP in the transplanted lungs, especially in hereditary PAP. The hereditary form of PAP is an ultra-rare condition caused by genetic mutations in genes encoding for the granulocyte macrophage-colony stimulating factor (GM-CSF) receptor, and intrinsically affects bone marrow derived-monocytes, which differentiate into macrophages in the lung. Consequently, these macrophages typically display disrupted GM-CSF receptor-signaling, causing defective surfactant clearance. Bone marrow/hematopoietic stem cell transplantation may potentially reverse the lung disease in hereditary PAP. In patients with hereditary PAP undergoing lung transplantation, post-lung transplant recurrence of PAP may theoretically be averted by subsequent hematopoietic stem cell transplantation, which results in a graft-versus-disease (PAP) effect, and thus could improve long-term outcome. We describe the successful long-term post-transplant outcome of a unique case of end-stage respiratory failure due to hereditary PAP-induced pulmonary fibrosis, successfully treated by bilateral lung transplantation and subsequent allogeneic hematopoietic stem cell transplantation. Our report supports treatment with serial lung and hematopoietic stem cell transplantation to improve quality of life and prolong survival, without PAP recurrence, in selected patients with end-stage hereditary PAP

Bos op arme gronden

Onder arme groeiplaatsen worden vooral de zandgronden verstaan. In Nederland liggen ze in het oosten en het zuiden van het land en ze lopen door naar de zandgronden in het noorden van Vlaanderen. De duinengordel langs de Noordzeekust behoort ook tot deze categorie. Zandgronden kunnen verder ingedeeld worden volgens hun geologische ontstaanswijze. Er kan onderscheid gemaakt worden tussen afzettingen door zee, rivieren of de wind, die bovendien uit het tertiair of het quartair tijdvak kunnen dateren. Zowel in Vlaanderen als Nederland ligt het grootste deel van het huidige bosareaal op de arme zandgronden: in Vlaanderen is het 60% van het totale areaal (90.000 ha) en in Nederland 86% (270.000 ha)

Bosomvorming: noodzaak en praktijk van een effectgerichte maatregel tegen verzuring en vermesting

B

Allometric biomass equations for Scots pine (Pinus sylvestris L.) seedlings during the first years of establishment in dense natural regeneration

International audienceA dense natural regeneration of Scots pine (Pinus sylvestris L.) exhibits a considerable biomass build-up in the first four years, with amounts of 7.03 Mg ha-1 for aboveground biomass, and 0.88 Mg ha-1 for coarse root biomass (> 1 mm). Power equations were developed, which relate collar diameter (ranging from 0.3 to 2.7 cm) and height to total aboveground and coarse root biomass of two, three and four-year-old seedlings in a regeneration of 16 seedlings m-2 at one site in Belgium. During the first years of establishment, seedling allometry changes with age, whilst the density remains constant. Biomass equations developed for one of the three ages can produce biased predictions for the other ages. Even when an equation is based on data for all ages and information on height is included, age still has to be considered as a potential predictor variable. For pooled ages, linear regression after logarithmic transformation of the power equation, selected other predictors than weighted non-linear regression. The former approach indicated significant interactions between predictors, while the latter does not reveal interactions.Équations d'allométrie de biomasse pour semis de pin sylvestre (Pinus sylvestris L.) dans les premières années d'établissement d'une régénération naturelle dense. Une régénération naturelle dense de pin sylvestre (Pinus sylvestris L.) montre une accroissement considérable de biomasse dans les quatre premières années, avec des quantités de 7,03 Mg ha-1 pour la biomasse aérienne et 0,88 Mg ha-1 pour la biomasse des grosses racines (> 1 mm). Des équations de type puissance mettant en relation le diamètre au niveau du collet racinaire (intervalle de 0,3 à 2,7 cm) et la hauteur avec la biomasse aérienne et la biomasse des grosses racines de semis de pin sylvestre âgés de deux, trois et quatre ans ont été développées dans une régénération d'une densité de 16 semis m-2 sur un site en Belgique. Entre la deuxième et la quatrième année, à densité stationnaire, la relation d'allométrie des semis change avec l'âge. Les équations de biomasse développées pour les semis d'un même âge, peuvent produire des prédictions erronées pour les autres âges. Même en utilisant des donnés de tous les âges et la variable hauteur, l'âge doit être considéré comme une variable potentielle dans l'analyse de régression. En utilisant des donnés de tous les âges, l'analyse de régression linéaire a retenu différentes variables que l'analyse de régression non-linéaire pondérée. La première désignait des interactions significatives, tandis que la dernière ne considère pas les interactions

Pathways of stand development in ageing Pinus sylvestris forests

Question: What are the main pathways of long-term stand development in forest ecosystems on oligotrophic and acidic sandy soils? Location: Nine forest reserves at different locations in The Netherlands: all ageing Pinus sylvestris forests that are no longer managed and where massive regeneration of broad-leaved species is often reported. Methods: Agglomerative cluster analysis was used to define structural classes from forest reserve data. Sequences of structural classes, representing different trajectories of stand development, were constructed with the aid of a process based gap model. Results: Four main pathways of stand development could be distinguished. Three pathways are linked to gap dynamics, and lead towards dominance of Betula, Quercus or Fagus. They differ in light availability for regeneration and/or seed tree availability. The fourth pathway comprises of development patterns after major disturbances. Conclusions: The new methodological approach, combining the empirical strength of forest reserve data with the predictive ability of a process based model, made it possible to detail and quantify insights into structure and dynamics of forests on poor sandy soils. Some factors not included in the study can substantially influence pathways, especially those where Quercus and Fagus potentially play an important role