Transmission-mode MALDI-2 mass spectrometry imaging of cells and tissues at subcellular resolution.

Matrix-assisted laser desorption-ionization mass spectrometry imaging in transmission-mode geometry (t-MALDI-MSI) can provide molecular information with a pixel size of 1 µm and smaller, which makes this label-free method highly interesting for characterizing the chemical composition of tissues and cells on a (sub)cellular level. However, a major hindrance for wider use of the technology is the reduced ion abundance at small pixel sizes. Here we mitigate this problem by use of laser-induced post-ionization (MALDI-2) and by adapting a t-MALDI-2 ion source to an Orbitrap mass analyzer. We demonstrate the crucial sensitivity and accuracy boosts that are achieved with this combination by visualizing the distribution of numerous phospho- and glycolipids in mouse cerebellum and kidney slices, and in cultured Vero B4 cells. With brain tissue, a pixel size of 600 nm was achieved. Our method could constitute a valuable new tool for research in cell biology and biomedicine.

Transplanted human cord blood-derived unrestricted somatic stem cells improve left-ventricular function and prevent left-ventricular dilation and scar formation after acute myocardial infarction.

OBJECTIVE: Functional improvement after acute myocardial ischaemia (MI) has been achieved by transplantation of different adult stem and progenitor cell types. It is controversial whether these cell types are able to form novel functional myocardium. Alternatively, graft-related or immune-related paracrine mechanisms may preserve existing myocardium, improve neovascularisation, affect tissue remodelling or induce endogenous de novo formation of functional myocardium. We have applied an alternative somatic cell type, human cord-blood-derived unrestricted somatic stem cells (USSCs) in a porcine model of acute MI. METHODS: USSCs were transplanted into the acutely ischaemic lateral wall of the left ventricle (LV). LV dimension and function were assessed by transoesophageal echocardiography (TEE) pre-MI, immediately post-MI, 48 hours and 8 weeks after USSC injection. Additionally, apoptosis, mitosis and recruitment of macrophages were examined 48 hours post-engraftment. RESULTS: Gender-specific and species-specific FISH/immunostaining failed to detect engrafted donor cells 8 weeks post-MI. Nevertheless, cell treatment effectively preserved natural myocardial architecture. Global left ventricular ejection fraction (LVEF) before MI was 60% (7%). Post-MI, LVEF decreased to 34% (8%). After 8 weeks, LVEF had further decreased to 27% (6%) in the control group and recovered to 52% (2%) in the USSC group (p<0.01). Left-ventricular end-diastolic volume (LVEDV) before MI was 28 (2) ml. 8 weeks post-MI, LVEDV had increased to 77 (4) ml in the control group. No LV dilation was detected in the USSC group (LVEDV: 26 (2) ml, p<0.01). Neither apoptosis nor recruitment of macrophages and mitosis were different in either groups. CONCLUSIONS: Transplantation of USSCs significantly improved LV function and prevented scar formation as well as LV dilation. Since differentiation, apoptosis and macrophage mobilisation at infarct site were excluded as underlying mechanisms, paracrine effects are most likely to account for the observed effects of USSC treatment.

[Suspicion of a newly appearing hypertrophic obstructive cardiomyopathy in a patient treated for hepatocellular carcinoma]. / Verdacht auf neu aufgetretene hypertrophe obstruktive Kardiomyopathie bei hepatozellulärem Karzinom.

HISTORY AND ADMISSION FINDINGS: A 42-year-old women presented with shortness of breath, tachycardia and weakness to our department. Five years ago she had been diagnosed with hepatocellular carcinoma for which an extended hemihepatectomy had been performed. INVESTIGATIONS, DIAGNOSIS AND TREATMENT: The clinical examination revealed a systolic murmur over the artic region. Echocardiography showed an hypertrophed interventricular septum with signs like those in hypertrophic obstructive cardiomyopathy. Ultrasound demonstrated a cystic mass in the pelvis highly suspicious of a metastasis of a hepatocellular carcinoma. Fine needle biopsy confirmed the diagnosis of a metastatic lesion of hepatocellular carcinoma. Computed tomography demonstrated metastase in the lung and a space-occupying in the interventricular septum. The patients underwent resection of the lung and pelvic metastasis and died a few weeks later. CONCLUSION: This case demonstrates the rare occurence of a metastasis to the heart, imitating obstructive cardiac myopathy, in a patient with hepatocellular carcinoma.

Clinically applicable 7-Tesla magnetic resonance visualization of transplanted human adult stem cells labeled with CliniMACS nanoparticles.

BACKGROUND: Intra-myocardial transplantation of bone marrow derived cells is currently under clinical evaluation as a therapy for heart failure. A major limitation of all clinical studies for myocardial restoration through cell transfer is the inability to track the fate of the transplanted cells. We present a clinically applicable technique using advanced ultra high-field 7-Tesla (7T) magnetic resonance imaging (MRI) of nanoparticle-labeled transplanted human EPCs in porcine ischemic hearts. METHODS: CD133 positive cells were isolated from bone marrow by magnetic bead selection. Positive cells (5 - 8 x 10 (6) cells) were transplanted into porcine ischemic myocardium (n = 8). Control animals (n = 3) received a medium injection. MRI on a 7T scanner was performed to demonstrate the distribution of the EPCs. RESULTS: CD133+ cells were identified on gradient echo images (T(1)-weighted) within the myocardium 4 weeks after transplantation. CONCLUSIONS: Magnetically labeled EPCs transplanted for therapeutic neovascularization or reduction of infarct size in myocardial ischemia can be visualized by MRI at high-field strengths.

Atrial reentrant tachycardia after surgery for congenital heart disease: endocardial mapping and radiofrequency catheter ablation using a novel, noncontact mapping system.

BACKGROUND: The purpose of the present study was to determine the role of a novel, noncontact mapping system for assessing a variety of atrial reentrant tachycardias (ART) in patients after the surgical correction of congenital heart disease. METHODS AND RESULTS: In 14 patients, an electrophysiological study using the Ensite 3000 system was performed to assess ARTs resistant to medical treatment. Sixteen different forms of ART were inducible in the 14 patients studied. The reentrant circuit of all ARTs could be characterized and localized with respect to anatomic landmarks such as atriotomy scars, intraatrial patches/baffles, and cardiac structures. In 15 of the 16 ARTs (in 13 of the 14 patients), a target area of the reentrant circuit for radiofrequency current application (ie, an area of conduction between 2 anatomical obstacles such as surgical barriers and cardiac structures of electrical isolation) could be localized within the systemic venous atrium. Nine patients exhibited macroreentry, and 4 showed microreentry. In 12 patients, ART could be terminated by creating linear radiofrequency current lesions (75 degrees C, 180 to 390 s). Completeness of linear lesions after radiofrequency current delivery was proven by analyzing color-coded isopotential maps of atrial activation while applying atrial pacing techniques. The mean duration of the procedures was 286 minutes (range, 130 to 435 minutes); fluoroscopy time ranged from 7 to 33.8 minutes (mean, 17.4 minutes). CONCLUSIONS: In patients with ART after the surgical correction of congenital heart disease, the use of the noncontact mapping system allows for characterization of the tachycardia and guidance for effective radiofrequency current delivery.

Noninvasive diagnosis in patients with undocumented tachycardias: value of the adenosine test to predict AV nodal reentrant tachycardia.

INTRODUCTION: Patients with symptoms suggestive of paroxysmal supraventricular tachycardia (PSVT) but no tachycardia documentation often undergo diagnostic electrophysiologic study. In dual AV node physiology with AV node reentrant tachycardia (AVNRT), the anterograde fast pathway is more sensitive than the slow pathway to the effects of adenosine. The purpose of the study was to test the hypothesis that adenosine can be used as a bedside test for the diagnosis of dual AV node physiology and hence for AVNRT. METHODS AND RESULTS: During electrophysiologic study, 37 patients without prior documentation but symptoms indicative for PSVT received incremental dosages of adenosine during sinus rhythm until second-degree or greater AV block was observed. Suggestive signs of dual AV node physiology on the surface ECG (sudden jump of PQ interval > or = 50 msec) were found in 13 (76%) of 17 patients with inducible AVNRT but in only 1 (5%) of the remaining patients (P < 0.01). In the AVNRT group, the maximal increase of the PQ interval between two beats was greater (88+/-45 msec) than in the remaining 20 patients (17+/-11 msec) (P < 0.01). CONCLUSION: Careful evaluation of surface ECG during administration of adenosine helps to identify patients prone to AVNRT. The adenosine test is a valuable noninvasive adjunct in patients with undocumented palpitations suggestive of PSVT.

Utility of a rapid fecal latex agglutination test detecting the neutrophil protein, lactoferrin, for diagnosing inflammatory causes of chronic diarrhea.

OBJECTIVE: The utility of tests for fecal neutrophils in the setting of chronic diarrhea has not been established. The purpose of this study was to determine the causes of chronic diarrhea associated with fecal neutrophils. METHODS: One fecal specimen from each of 10 normal subjects, 26 patients with known microscopic colitis, 13 with celiac sprue, eight with Crohn's disease, four with ulcerative colitis, and 103 with chronic diarrhea of unknown origin, as well as 10 fecal specimens from a patient with chronic nongranulomatous enterocolitis were analyzed blindly for the presence of a neutrophil granule protein called lactoferrin using a commercial latex agglutination kit. Diagnostic evaluation of the 103 patients with chronic diarrhea was carried out to determine the diagnostic accuracy of this test for chronic inflammatory bowel disease. RESULTS: None of the normal control subjects, three of 39 patients with microscopic colitis or celiac sprue, all 10 specimens from the patient with enterocolitis, and all 12 control patients with ulcerative colitis or Crohn's disease had a positive fecal lactoferrin test. Eleven of 103 patients with chronic diarrhea presenting without a diagnosis had a positive test, and all were diagnosed with an inflammatory condition of the colon (five-, ulcerative colitis; four-, Crohn's disease; one-, ischemic colitis; and one-, microscopic colitis). Only one patient with inflammatory bowel disease had a negative lactoferrin test. The sensitivity, specificity, and positive and negative predictive values of the fecal lactoferrin test for ulcerative or Crohn's colitis were 90%, 98%, 82%, and 99%, respectively. CONCLUSION: The major cause of fecal neutrophils in patients with chronic diarrhea is chronic inflammatory bowel disease of the colon. The latex agglutination test for fecal lactoferrin offers a highly sensitive, specific, and simple means for detection of fecal neutrophils in these patients.