Lung transplantation in cystic fibrosis: Trends and controversies

This article is not an overview of all facets of lung transplantation in cystic fibrosis (CF), but rather it is intended as a review of current allocation controversies, as well as of trends in diagnostics and management in lung transplant recipients and in patients with end-stage lung disease. Despite changes in donor and recipient selection, long-term survival in pediatric lung transplant has continued to be limited by chronic lung allograft dysfunction (CLAD). Due to, in part, this short survival benefit, transplant continues to be an appropriate option for only a subset of pediatric patients with CF. The feasibility of transplant as a therapeutic option is also affected by the limited pediatric organ supply, which has moreover contributed to controversy over lung allocation. Debates over the allocation of this scarce resource, however, may also help to drive innovation in the field of lung transplant. Longer pretransplant survival—as aided by new lung bypass technologies, for example—could help to alleviate organ shortages, as well as facilitate the transport of organs to suitable pediatric recipients. Improved diagnosis and treatment for CLAD and for antibody-mediated rejection have the potential to extend survival in pediatric lung transplant. Regardless, the relative rarity of transplant could pose future challenges for pediatric lung transplant programs, which require adequate numbers of patients to maintain proper expertise

Towards a critical realist epistemology?

When critical realists consider epistemology they typically start from “epistemological relativism.” We find this position necessary, but we also find it insufficient because it lacks a critique of the highly unequal social relations among observers themselves—relations that shape the very production of knowledge. While it is indeed the case that all knowledge is fallible, it is also the case that all knowledge is positioned, with a particular standpoint. What is more, the social power relations between standpoints organize the production of truth in ways that produce systematic distortions. In this paper, we propose a critical realist social epistemology. We introduce feminist standpoint theory and postcolonial theory as our suggested interventions into critical realism and we use two case studies of existing work to highlight i) the social production of truth and the real, and ii) what is at stake for radicalizing epistemology in critical realism. In so doing, our paper emphasizes the epistemic complexities that continuously shape ontology, a commitment to subaltern voices or experiences, and a thorough interrogation of the relations between positions of knowledge production.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162717/2/jtsb12248_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162717/1/jtsb12248.pd

The impact of conventional and nonconventional inhalants on children and adolescents

AimInhalant abuse in the adolescent population is a growing concern for care givers, communities, physicians, and medical providers. The aim of this article is to provide a review of the literature about this new challenge. In addition, it raises awareness about recent health policy rulings.MethodsReview of the literature was done.ResultsIn this review article, the prevalence of different modes of inhalant use and abuse in children and young adults and their potential health implications will be examined: Cigarettes, ENDS (E Cigarettes), Hookah, Marijuana, and Huffing. Additionally, marketing and advertising tactics will be reviewed to understand how they target this population. A review of current health policy recommendations from the FDA, American Thoracic Society, and the American Academy of Pediatrics will also be discussed.ConclusionThe rapid rise in e‐cigarette and hookah use in school aged children should trigger a call to action in the medical and public health communities. Health policy recommendations need to be made to reduce the level of adolescent substance abuse.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142898/1/ppul23836_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142898/2/ppul23836.pd

Presence of matrix-specific antibodies in affinity-purified polyclonal antibodies

In general, antigen affinity columns made with commercially prepared activated affinity supports bind antibody specific for the coupled antigen. Nonetheless, in some cases affinity purification may yield antibodies to molecules other than the molecule of interest. In this report, we demonstrate such an occurrence: an antibody which adsorbs to an Affi-Prep 10 affinity matrix was found in the serum of sheep immunized against calmodulin. The contaminating antibody bound to cell nuclei and condensed chromosomes; the composition of the Affi-Prep 10 matrix suggests that the antibody may cross-react to the sugar-phosphate backbone of DNA. We were able to remove the contaminating antibody from the anti-calmodulin by passing the affinity-purified mixture over an antigen-free Affi-Prep 10 column.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29497/1/0000583.pd

Usefulness of gene expression profiling of bronchoalveolar lavage cells in acute lung allograft rejection.

BackgroundChronic lung allograft dysfunction (CLAD) is the main limitation to long-term survival after lung transplantation. Because effective therapies are lacking, early identification and mitigation of risk factors is a pragmatic approach to improve outcomes. Acute cellular rejection (ACR) is the most pervasive risk factor for CLAD, but diagnosis requires transbronchial biopsy, which carries risks. We hypothesized that gene expression in the bronchoalveolar lavage (BAL) cell pellet (CP) could replace biopsy and inform on mechanisms of CLAD.MethodsWe performed RNA sequencing on BAL CPs from 219 lung transplant recipients with A-grade ACR (n = 61), lymphocytic bronchiolitis (n = 58), infection (n = 41), or no rejection/infection (n = 59). Differential gene expression was based on absolute fold difference >2.0 and Benjamini-adjusted p-value ≤0.05. We used the Database for Annotation, Visualization and Integrated Discovery Bioinformatics Resource for pathway analyses. For classifier modeling, samples were randomly split into training (n = 154) and testing sets (n = 65). A logistic regression model using recursive feature elimination and 5-fold cross-validation was trained to optimize area under the curve (AUC).ResultsDifferential gene expression identified 72 genes. Enriched pathways included T-cell receptor signaling, natural killer cell-mediated cytotoxicity, and cytokine-cytokine receptor interaction. A 4-gene model (AUC = 0.72) and classification threshold defined in the training set exhibited fair performance in the testing set; accuracy was 76%, specificity 82%, and sensitivity 60%. In addition, classification as ACR was associated with worse CLAD-free survival (hazard ratio = 2.42; 95% confidence interval = 1.29-4.53).ConclusionsBAL CP gene expression during ACR is enriched for immune response pathways and shows promise as a diagnostic tool for ACR, especially ACR that is a precursor of CLAD

Pediatric Transplantation in the United States, 1995–2004

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72899/1/j.1600-6143.2006.01271.x.pd

Expression analysis of G Protein-coupled receptors in mouse macrophages

Background. Monocytes and macrophages express an extensive repertoire of G Protein-Coupled Receptors (GPCRs) that regulate inflammation and immunity. In this study we performed a systematic micro-array analysis of GPCR expression in primary mouse macrophages to identify family members that are either enriched in macrophages compared to a panel of other cell types, or are regulated by an inflammatory stimulus, the bacterial product lipopolysaccharide (LPS). Results. Several members of the P2RY family had striking expression patterns in macrophages; P2ry6 mRNA was essentially expressed in a macrophage-specific fashion, whilst P2ry1 and P2ry5 mRNA levels were strongly down-regulated by LPS. Expression of several other GPCRs was either restricted to macrophages (e.g. Gpr84) or to both macrophages and neural tissues (e.g. P2ry12, Gpr85). The GPCR repertoire expressed by bone marrow-derived macrophages and thioglycollate- elicited peritoneal macrophages had some commonality, but there were also several GPCRs preferentially expressed by either cell population. Conclusion. The constitutive or regulated expression in macrophages of several GPCRs identified in this study has not previously been described. Future studies on such GPCRs and their agonists are likely to provide important insights into macrophage biology, as well as novel inflammatory pathways that could be future targets for drug discovery