Blood transfusion during cardiac surgery is associated with inflammation and coagulation in the lung: a case control study

Blood transfusion is associated with increased morbidity and mortality in cardiac surgery patients, but cause-and-effect relations remain unknown. We hypothesized that blood transfusion is associated with changes in pulmonary and systemic inflammation and coagulation occurring in patients who do not meet the clinical diagnosis of transfusion-related acute lung injury (TRALI). We performed a case control study in a mixed medical-surgical intensive care unit of a university hospital in the Netherlands. Cardiac surgery patients (n = 45) were grouped as follows: those who received no transfusion, those who received a restrictive transfusion (one two units of blood) or those who received multiple transfusions (at least five units of blood). Nondirected bronchoalveolar lavage fluid (BALF) and blood were obtained within 3 hours postoperatively. Normal distributed data were analyzed using analysis of variance and Dunnett's post hoc test. Nonparametric data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests. Restrictive transfusion increased BALF levels of interleukin (IL)-1β and D-dimer compared to nontransfused controls (P < 0.05 for all), and IL-1β levels were further enhanced by multiple transfusions (P < 0.01). BALF levels of IL-8, tumor necrosis factor α (TNFα) and thrombin-antithrombin complex (TATc) were increased after multiple transfusions (P < 0.01, P < 0.001 and P < 0.01, respectively) compared to nontransfused controls, but not after restrictive transfusions. Restrictive transfusions were associated with increased pulmonary levels of plasminogen activator inhibitor 1 compared to nontransfused controls with a further increase after multiple transfusions (P < 0.001). Concomitantly, levels of plasminogen activator activity (PAA%) were lower (P < 0.001), indicating impaired fibrinolysis. In the systemic compartment, transfusion was associated with a significant increase in levels of TNFα, TATc and PAA% (P < 0.05). Transfusion during cardiac surgery is associated with activation of inflammation and coagulation in the pulmonary compartment of patients who do not meet TRALI criteria, an effect that was partly dose-dependent, suggesting transfusion as a mediator of acute lung injury. These pulmonary changes were accompanied by systemic derangement of coagulatio

Mechanical Ventilation and the Titer of Antibodies as Risk Factors for the Development of Transfusion-Related Lung Injury

Purpose. Onset of transfusion-related acute lung injury (TRALI) is suggested to be a threshold-event. Data is lacking on the relation between titer of antibodies infused and onset of TRALI. We determined whether onset of TRALI is dependent on the titer of MHC-I antibodies infused in a combined model of ventilator-induced lung injury and antibody-induced TRALl. Methods. BALB/c mice were ventilated for five hours with low (7.5 ml/kg) or high (15 ml/kg) tidal volume. After three hours of MV, TRALI was induced by infusion of 0.5 mg/kg, 2.0 mg/kg or 4.5 mg/kg MHC-I antibodies. Control animals received vehicle. After five hours of MV, animals were sacrificed. Results. MV with high tidal volumes resulted in increased levels of all markers of lung injury compared to animals ventilated with low tidal MV. In ventilator-induced lung injury, infusion of 4.5 mg/kg of antibodies further increased pulmonary wet-to-dry ratio, pulmonary neutrophil influx and pulmonary KC levels, whereas infusion of lower dose of antibodies did not augment lung injury. In contrast, mice ventilated with low tidal volumes did not develop lung injury, irrespective of the dose of antibody used. Conclusions. In the presence of injurious MV, onset of TRALI depends on the titer of antibodies infused

Suspected Lynch syndrome associated MSH6 variants: A functional assay to determine their pathogenicity

Lynch syndrome (LS) is a hereditary cancer predisposition caused by inactivating mutations in DNA mismatch repair (MMR) genes. Mutations in the MSH6 DNA MMR gene account for approximately 18% of LS cases. Many LS-associated sequence variants are nonsense and frameshift mutations that clearly abrogate MMR activity. However, missense mutations whose functional implications are unclear are also frequently seen in suspected-LS patients. To conclusively diagnose LS and enroll patients in appropriate surveillance programs to reduce morbidity as well as mortality, the functional consequences of these variants of uncertain clinical significance (VUS) must be defined. We present an oligonucleotide-directed mutagenesis screen for the identification of pathogenic MSH6 VUS. In the screen, the MSH6 variant of interest is introduced into mouse embryonic stem cells by site-directed mutagenesis. Subsequent selection for MMR-deficient cells using the DNA damaging agent 6-thioguanine (6TG) allows the identification of MMR abrogating VUS because solely MMR-deficient cells survive 6TG exposure. We demonstrate the efficacy of the genetic screen, investigate the phenotype of 26 MSH6 VUS and compare our screening results to clinical data from suspected-LS patients carrying these variant alleles

Personalized E-Coaching in Cardiovascular Risk Reduction: A Randomized Controlled Trial

Barts Charity for the HAPPY London study (grant number 437/1412

<i>ATP5PO </i>levels regulate enteric nervous system development in zebrafish, linking Hirschsprung disease to Down Syndrome

Hirschsprung disease (HSCR) is a complex genetic disorder characterized by the absence of enteric nervous system (ENS) in the distal region of the intestine. Down Syndrome (DS) patients have a &gt;50-fold higher risk of developing HSCR than the general population, suggesting that overexpression of human chromosome 21 (Hsa21) genes contribute to HSCR etiology. However, identification of responsible genes remains challenging. Here, we describe a genetic screening of potential candidate genes located on Hsa21, using the zebrafish. Candidate genes were located in the DS-HSCR susceptibility region, expressed in the human intestine, were known potential biomarkers for DS prenatal diagnosis, and were present in the zebrafish genome. With this approach, four genes were selected: RCAN1, ITSN1, ATP5PO and SUMO3. However, only overexpression of ATP5PO, coding for a component of the mitochondrial ATPase, led to significant reduction of ENS cells. Paradoxically, in vitro studies showed that overexpression of ATP5PO led to a reduction of ATP5PO protein levels. Impaired neuronal differentiation and reduced mitochondrial ATP production, were also detected in vitro, after overexpression of ATP5PO in a neuroblastoma cell line. Finally, epistasis was observed between ATP5PO and ret, the most important HSCR gene. Taken together, our results identify ATP5PO as the gene responsible for the increased risk of HSCR in DS patients in particular if RET variants are also present, and show that a balanced expression of ATP5PO is required for normal ENS development.</p

Fine mapping of the 9q31 Hirschsprung’s disease locus

Hirschsprung’s disease (HSCR) is a congenital disorder characterised by the absence of ganglia along variable lengths of the intestine. The RET gene is the major HSCR gene. Reduced penetrance of RET mutations and phenotypic variability suggest the involvement of additional modifying genes in the disease. A RET-dependent modifier locus was mapped to 9q31 in families bearing no coding sequence (CDS) RET mutations. Yet, the 9q31 causative locus is to be identified. To fine-map the 9q31 region, we genotyped 301 tag-SNPs spanning 7 Mb on 137 HSCR Dutch trios. This revealed two HSCR-associated regions that were further investigated in 173 Chinese HSCR patients and 436 controls using the genotype data obtained from a genome-wide association study recently conducted. Within one of the two identified regions SVEP1 SNPs were found associated with Dutch HSCR patients in the absence of RET mutations. This ratifies the reported linkage to the 9q31 region in HSCR families with no RET CDS mutations. However, this finding could not be replicated. In Chinese, HSCR was found associated with IKBKAP. In contrast, this association was stronger in patients carrying RET CDS mutations with p = 5.10 × 10−6 [OR = 3.32 (1.99, 5.59)] after replication. The HSCR-association found for IKBKAP in Chinese suggests population specificity and implies that RET mutation carriers may have an additional risk. Our finding is supported by the role of IKBKAP in the development of the nervous system