Elevated inflammation markers in pheochromocytoma compared to other forms of hypertension

OBJECTIVE: To investigate the effect of long-term catecholamine excess in pheochromocytoma on leukocyte and platelet count and on proteins of acute-phase response. METHODS: Fifteen subjects with pheochromocytoma, 16 with primary aldosteronism, 18 with essential hypertension and 17 healthy controls were studied. Sixteen subjects with pheochromocytoma were investigated after tumor removal. Leukocyte, neutrophil and platelet count, as well as C-reactive protein were measured in all subjects, while fibrinogen, alpha(1)-antitrypsin, alpha(2)-macroglobulin, orosomucoid, transferrin and prealbumin were only measured in subjects with pheochromocytoma, primary aldosteronism and essential hypertension. RESULTS: Subjects with pheochromocytoma showed significantly higher leukocyte [7.5 +/- 0.9 10(9)/l, p < 0.001 vs. primary aldosteronism (5.4 +/- 0.9 10(9)/l) and healthy controls (5 +/- 0.9 10(9)/l), p = 0.04 vs. essential hypertension (6.3 +/- 1.6 10(9)/l)], neutrophil (p < 0.001 vs. primary aldosteronism and healthy subjects) and platelet counts (p < 0.001 vs. primary aldosteronism; p = 0.01 vs. essential hypertension) compared to the other groups of subjects. Similar results were obtained for positive proteins of acute-phase response in subjects with pheochromocytoma [C-reactive protein: 0.62 +/- 0.52 mg/dl, p < 0.001 vs. healthy subjects (0.08 +/- 0.08 mg/dl), p = 0.001 vs. primary aldosteronism (0.17 +/- 0.19 mg/dl), p = 0.04 vs. essential hypertension (0.31 +/- 0.26 mg/dl); fibrinogen: p = 0.02 vs. primary aldosteronism; orosomucoid: p = 0.005 vs. primary aldosteronism; alpha(2)-macroglobulin: p = 0.009 vs. primary aldosteronism]. No significant differences were found in plasma levels of alpha(1)-antitrypsin, transferrin and prealbumin. Tumor removal led to a significant decrease in leukocyte (p = 0.004), neutrophil (p = 0.007) and platelet count (p = 0.003) and also to a significant decrease in acute-phase proteins (C-reactive protein: p = 0.03, fibrinogen: p = 0.008, alpha(1)-antitrypsin: p = 0.003, orosomucoid: p = 0.04). CONCLUSIONS: Chronic catecholamine excess in pheochromocytoma is accompanied by an increase in inflammation markers which was reversed by the tumor removal.     

The relationship of eosinophil granule proteins to ions in the sputum of patients with cystic fibrosis

Increased sputum levels of eosinophil granule proteins have been reported despite normal eosinophil numbers in peripheral blood and in the lung in cystic fibrosis (CF). Mechanisms of eosinophil priming and activation are still unclear in CF. In the present study we investigated whether ion concentrations in the sputa of CF patients are related to eosinophil activity. We assessed concentrations of eosinophil cationic protein (ECP), eosinophil protein X (EPX), major basic protein (MBP) and ions (Na+, Cl-, Ca2+, Mg2+) in sputum samples of 29 children with CF as well as in 10 controls with bronchial asthma. Patients with CF demonstrated significantly higher levels of ECP, Na+, Cl- and Ca2+ levels than asthmatics (P < 0.04, P < 0.0001, P < 0.0001, P < 0.02). No differences were seen between concentrations of EPX and Mg2+ in the two groups. In CF, eosinophil granule proteins correlated significantly with Ca2+ and Mg2+ concentrations (ECP, P < 0.0001, r = 0.65, P < 0.0001, r = 0.66; MBP, P < 0.03, r = 0.41, P < 0.03, r = 0.42), furthermore inversely with Cl- concentrations (ECP, P < 0. 0003, r = - 0.63; EPX, P < 0.02, r = - 0.45; MBP, P < 0.03, r = - 0. 41) but not with Na+ levels. ECP, Na+ and Cl- were also correlated with lung function variables (FVC, P < 0.04, r = - 0.38, P < 0.02, r = 0.44, P < 0.03, r = 0.41; FEV1, P < 0.007, r = - 0.49, P < 0.006, r = 0.5, P < 0.008, r = 0.48; MEF50, P < 0.003, r = - 0.54, NS, P < 0.03, r = 0.42; MEF25, P < 0.039, r = - 0.4, P < 0.005, r = 0.51, P < 0.05, r = 0.37). Our results demonstrated a significant relationship of eosinophil degranulation and ions in CF, indicating that ion composition in CF sputa may be at least partly be responsible for high levels of eosinophil products despite low eosinophil numbers.     

Importance of extrasegmental vessels for spinal cord blood supply in a chronic porcine model.

OBJECTIVE: Our purpose was to investigate the interaction of the important components of spinal cord blood supply in the pig model to enable its use for future studies of spinal cord protection. METHODS: Twenty-five juvenile pigs (20-22 kg) underwent serial intercostal (IC) or lumbar artery (LA) ligation until disappearance of motor evoked potentials (MEPs). Pigs underwent sequential craniocaudal IC/LA ligation alone (n=5); following clamping of both subclavian arteries (n=4), or clamping of the median sacral artery (MSA, n=4). Animals also underwent serial caudocranial clamping of LA/IC alone (n=4); preceded by clamping of the subclavian arteries (n=4), or of the MSA (n=4). Results were verified by Tarlov's scores and perioperative angiography. RESULTS: All animals with MEP loss suffered postoperative paraplegia. Groups were equivalent with regard to stable arterial pressures (64.6+/-3.1 degrees C) throughout the experiment, temperature (36+/-1.1 degrees C) and other physiological parameters. Mean number of clamped IC/LA before MEP loss for cranio-caudal clamping direction was 12.8+/-0.8 for segmental arteries isolated, 9+/-0.8 if both subclavian arteries were ligated previously and only 4.3+/-0.5 IC if the median sacral artery was clamped before. Mean number of clamped LA for caudo-cranial clamping direction was 5.8+/-0.9 for segmental lumbar arteries, 5.5+/-0.6 LA if both subclavian arteries were ligated previously and 3.5+/-0.6 if the median sacral artery was clamped before. CONCLUSION: This study confirms the importance of lumbar and MSA arteries to cord viability. It documents the interaction of the subclavian and MSA (roughly equivalent to the hypogastric arteries in humans) with segmental vessels in providing spinal cord blood supply. It also provides the physiologic basis for use of the pig model for studies of spinal cord protection in aortic surgery.     

Der Einsatz von menschlichen Herzklappen (?Homografts“) in der Therapie von Herzklappenerkrankungen— Eine übersicht

Seit dem ersten erfolgreichen Ersatz einer Aortenklappe mit Hilfe einer mechanischen Prothese in Jahre 1960 hat es eine rasante Entwicklung neuer Materialien und Techniken gegeben. Dennoch weisen alle herkömmlichen Klappen Probleme auf. Wesentlich sind hier thrombembolische oder hämorrhagische Komplikationen, Klappenendokarditis und ein nicht physiologisches Flussprofil. Der Einsatz menschlicher kryokonservierter Herzklappentransplantate (Homografts) hat sich in der Therapie von Herzklappenerkrankungen bis heute zu einem sicheren Verfahren in der Kardiochirurgie etabliert. Obwohl der ideale Herzklappenersatz noch definiert werden muss, kommt der humane Homograft diesem im Vergleich zu den mechanischen oder biologischen Ventilen am nächsten. Homografts gewährleisten eine nahezu normale Anatomie mit guten hämodynamischen Eigenschaften in Ruhe und unter Belastung. Aufgrund des sehr geringen Auftretens thrombembolischer Ereignisse ist eine Antikoagulanzientherapie in der Regel nicht notwendig. Besonders bei Endokarditis haben sich Homografts wegen ihrer niedrigen Reinfektionsrate als besonders resistent gegenüber Infektionen gezeigt. Homografts sind jedoch entsprechend dem Organspendermangel in der gesamten Transplantationsmedizin nur begrenzt verfügbar, besitzen ein immunologisches Potenzial, unterliegen durch Verkalkung erneut degenerativen Prozessen und haben daher beschränkte Langzeitfunktion. Zusammenfassend kann gesagt werden, dass Homografts für eine bestimmte Gruppe von Patienten attraktivere Alternativen zu den mechanischen oder xenobiologischen Prothesen darstellen. Die behandelnden Ärzte sollten über die verfügbaren Implantate, die Operationsmethoden und die zu erwartenden Ergebnisse informiert sein.     

Ketoprofen and prednisolone do not modulate neutrophil CR1, CR3 and Fc gamma RIII expression in healthy volunteers.

We assessed the effect of ketoprofen and prednisolone on the complement receptors (CR1 and CR3) and Fc gamma RIII expression on polymorphonuclears in an ex vivo study, using a randomized, single-blind, placebo-controlled, parallel design. Twenty-four healthy, male, Caucasian volunteers received either oral ketoprofen 100 mg twice daily, or prednisolone 5 mg twice daily, or placebo twice daily for 7.5 days. CR1, CR3 and Fc gamma RIII on unstimulated and FMLP-, C5a-, LTB4-, and GM-CSF-stimulated neutrophils were assessed using specific monoclonal antibodies and flow cytometry. No statistically significant drug effect was found for CR1, CR3, and Fc gamma RIII expression on polymorphonuclears. An in vitro study also yielded negative results. These findings do not support the hypothesis that the effect of non-steroidal antiinflammatory drugs on neutrophils is due to CR1, CR3, or Fc gamma RIII modulation.     

Explorative two-locus linkage analysis suggests a multiplicative interaction between the 7q32 and 16p13 myoclonic seizures-related photosensitivity loci

In traits suspected to be governed by at least two loci, linkage analysis incorporating the joint action of both loci may improve the power to detect linkage, increase the precision of estimating locus positions and provide insight into the underlying etiological mechanism. Recently, we mapped two susceptibility loci for epilepsy-related photosensitivity (or photoparoxysmal response, PPR) at regions 7q32 (PPR1) and 16p13 (PPR2) in PPR families with prominent myoclonic seizures background (MS-related PPR). To follow-up these results and evaluate interaction effects between these regions, we conducted two-locus (2L) linkage analyses using parametric and non-parametric methods. The 2L linkage was calculated under a multiplicative (MULT) epistasis model, encompassing models where each locus is necessary but not sufficient for MS-related PPR and a heterogeneity (HET) model, encompassing models in which each locus is by itself sufficient but not necessary for MS-related PPR expression. We found maximal 2L linkage under the (MULT) model, which was significantly better than the 2L linkage under the (HET) model (P = 0.001). The 2L analyses gave no increase in power to detect linkage over the single-locus analyses nor did they improve location estimates at PPR1 and PPR2, as expected under a best-fit 2L (MULT) model in an affecteds-only analysis. Our findings suggest that the genes underlying the PPR1 and PPR2 susceptibility loci may have similar functions or act in the same biochemical pathway.     

Extracorporeal membrane oxygenation in spina bifida and (H1N1)-induced acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is characterized as an acute hypoxemic and/or hypercapnic respiratory failure seen in critically ill patients and is still, although decreased over the past few years, associated with high mortality. Furthermore, ARDS may be a life-threatening complication of H1N1 pneumonia. We report on a 45-year-old spina bifida patient with confirmed H1N1 influenza virus infection causing acute respiratory failure, who was successfully weaned from 42-day veno-venous extracorporeal membrane oxygenation (vv-ECMO) treatment with an excellent outcome. Due to the physical constitution of spina bifida patients, we experienced challenges concerning cannula positioning and mechanical ventilation settings during weaning.     

Discovery of a novel amino acid racemase through exploration of natural variation in Arabidopsis thaliana

Plants produce diverse low-molecular-weight compounds via specialized metabolism. Discovery of the pathways underlying production of these metabolites is an important challenge for harnessing the huge chemical diversity and catalytic potential in the plant kingdom for human uses, but this effort is often encumbered by the necessity to initially identify compounds of interest or purify a catalyst involved in their synthesis. As an alternative approach, we have performed untargeted metabolite profiling and genome-wide association analysis on 440 natural accessions of Arabidopsis thaliana. This approach allowed us to establish genetic linkages between metabolites and genes. Investigation of one of the metabolite–gene associations led to the identification of N-malonyl-d-allo-isoleucine, and the discovery of a novel amino acid racemase involved in its biosynthesis. This finding provides, to our knowledge, the first functional characterization of a eukaryotic member of a large and widely conserved phenazine biosynthesis protein PhzF-like protein family. Unlike most of known eukaryotic amino acid racemases, the newly discovered enzyme does not require pyridoxal 5′-phosphate for its activity. This study thus identifies a new d-amino acid racemase gene family and advances our knowledge of plant d-amino acid metabolism that is currently largely unexplored. It also demonstrates that exploitation of natural metabolic variation by integrating metabolomics with genome-wide association is a powerful approach for functional genomics study of specialized metabolism.Plants have the ability to create over 200,000 small compounds known as secondary or specialized metabolites (1). These chemically diverse compounds help mediate plant adaptation to their environment and play important roles in plant defense mechanisms, pigmentation, and development. In addition, many of these metabolites are desirable to humans as medicinal and nutritional compounds. Therefore, furthering our understanding of plant specialized metabolism will have profound impacts on various applications from crop improvement to human health.To date, only a small fraction of the chemical and catalytic space in plant specialized metabolism has been explored. Even in the best-studied model plant Arabidopsis thaliana, there are still many uncharacterized metabolites, and the vast majority of genes encoding enzymes implied to be involved in specialized metabolism do not have known associations with any metabolites. Several studies of Arabidopsis natural accessions (individuals collected from wild populations) revealed considerable qualitative and quantitative variation in the accumulation of various compounds such as glucosinolates, terpenoids, and phenylpropanoids (2–4). This extensive metabolite variation can be attributed to genetic variation in genes encoding enzymes and regulatory factors of the pathways involved; quantitative trait locus (QTL) mapping has successfully uncovered several genes involved in the production of these metabolites (3–7). Liquid chromatography–mass spectrometry (LC-MS)–based untargeted metabolic profiling has further extended such analysis to unknown metabolites, finding genetic contribution to the variation in at least three-fourths of detected mass peaks (8).Here we describe an integrated transdisciplinary platform, combining metabolomics, genetics, and genomics, to exploit the biochemical and genetic diversity of natural accessions of the model plant A. thaliana to uncover associations between genes and metabolites. Using this platform, we linked a differentially accumulating metabolite, identified through chemical analysis as N-malonyl-d-allo-isoleucine (NMD-Ile), to a previously uncharacterized gene identified as an amino acid racemase through reverse genetics and biochemical analysis.Amino acids exist in two forms; l-amino acids, the proteogenic form, and their enantiomorphs, d-amino acids. d-amino acids also play important structural and physiological roles in diverse life systems. In bacteria, d-amino acids confer cell-wall protease resistance and regulate cell-wall remodeling (9–11). d-amino acids were also found to be involved in signaling mechanisms in animal nervous systems and plant pollination (12, 13). Enzymes that catalyze the conversion of l-amino acids to d-amino acids are a class of isomerases known as amino acid racemases (14). Amino acid racemases are categorized into pyridoxal 5′ phosphate (PLP)-dependent and PLP-independent families. PLP-dependent racemases include AlaR, SerR, ArgR, and AspR and are found in both bacteria and eukaryotes, including mammals and plants. PLP-independent amino acid racemases include bacterial ProR, GluR, AspR, and diaminopimelate (DAP) epimerase. Except for DAP epimerase, which is required for the biosynthesis of Lys in bacteria and plants, ProR in Trypanosoma cruzi, the protozoan parasite responsible for Chagas disease, has been the only known eukaryotic PLP-independent racemase (15). The Arabidopsis amino acid racemase that we describe in this paper is a new member of the PLP-independent family, making its identification a significant addition to this class of enzymes.