4 research outputs found
Improved Resolution of Magnetic Resonance Microscopy in Examination of Skin Tumors
Magnetic resonance imaging has become increasingly important for visualization and tissue differentiation of internal organs. Because of limited resolution, investigation of skin has been of little diagnostic value so far. We combined a homogeneous magnetic field of 9.4 T, as used in magnetic resonance spectroscopy, with gradient fields of 11.7 G/cm and an imaging unit to obtain a voxel resolution of 40 × 40 × 300 μm3. With this magnetic resonance microscopy unit, we studied normal skin, 12 nevocellular nevi, 20 basal cell carcinomas, 8 melanomas, and 8 seborrheic keratoses after excision in vitro. The specimens were visualized in spin-echo images. The proton relaxation times T1 and T2 were determined for the different skin layers and tumor tissues. Interpretation of the spin-echo images was based on comparison with the correlating histology. Epidermis, dermis, subcutaneous tissue, and hair follicle complexes could be distinguished. Stratum corneum and hairs emitted no signal. All tumors presented as distinct, signal-rich, homogeneous structures within the dark, signal-poor dermis. Their shape corresponded to their outline in the histologic sections. Buds of superficial basal cell carcinomas could be resolved. The proton relaxation times T1 and T2 were significantly different among all skin layers and tumors. Our results demonstrate that with sufficient resolution, differentiation of skin tumors is possible using magnetic resonance imaging
NMR-Based Screening for Inborn Errors of Metabolism: Initial Results from a Study on Turkish Neonates
Ors, Rahmi/0000-0002-9089-1067WOS: 000376979100015PubMed: 25012580Approximately 1 in 400 neonates in Turkey is affected by inherited metabolic diseases. This high prevalence is at least in part due to consanguineous marriages. Standard screening in Turkey now covers only three metabolic diseases (phenylketonuria, congenital hypothyroidism, and biotinidase deficiency). Once symptoms have developed, tandem-MS can be used, although this currently covers only up to 40 metabolites. NMR potentially offers a rapid and versatile alternative. We conducted a multi-center clinical study in 14 clinical centers in Turkey. Urine samples from 989 neonates were collected and investigated by using NMR spectroscopy in two different laboratories. The primary objective of the present study was to explore the range of variation of concentration and chemical shifts of specific metabolites without clinically relevant findings that can be detected in the urine of Turkish neonates. The secondary objective was the integration of the results from a healthy reference population of neonates into an NMR database, for routine and completely automatic screening of congenital metabolic diseases. Both targeted and untargeted analyses were performed on the data. Targeted analysis was aimed at 65 metabolites. Limits of detection and quantitation were determined by generating urine spectra, in which known concentrations of the analytes were added electronically as well as by real spiking. Untargeted analysis involved analysis of the whole spectrum for abnormal features, using statistical procedures, including principal component analysis. Outliers were eliminated by model building. Untargeted analysis was used to detect known and unknown compounds and jaundice, proteinuria, and acidemia. The results will be used to establish a database to detect pathological concentration ranges and for routine screening
Lipoprotein and Metabolic Profiles Indicate Similar Cardiovascular Risk of Liver Steatosis and NASH
: Nonalcoholic fatty liver disease (NAFLD) affects about 25% of the global population, with no reliable noninvasive tests to diagnose nonalcoholic steatohepatitis (NASH) and to differentiate between NASH and nonalcoholic fatty liver (NAFL) (steatosis alone). It is unclear if NAFL and NASH differ in cardiovascular risk for patients. Here, we compared obese NAFLD patients with a healthy cohort to test whether cholesterol compounds could represent potential noninvasive markers and to estimate associated risks.
Serum samples of 46 patients with histologically confirmed NAFLD (17 NAFL, 29 NASH) who underwent bariatric surgery were compared to 32 (9 males, 21 females) healthy controls (HCs). We analyzed epidemiological data, liver enzymes, cholesterol and lipid profile, and amino acids. The latter were analyzed by nuclear magnetic resonance spectroscopy.
Total serum and high-density lipoprotein (HDL) cholesterol were significantly lower in the NAFLD group than in HCs, with a stronger reduction in NASH. Similar observations were made for sub-specification of HDL-p, HDL-s, SHDL-p, and LHDL-p cholesterols. Low-density lipoprotein (LDL)-s and LLDL-p cholesterol were significantly reduced in NAFLD groups. Interestingly, SLDL-p cholesterol was significantly higher in the NAFL group with a stronger elevation in NASH than in HCs. The amino acids alanine, leucin, and isoleucine were significantly higher in the NAFL and NASH groups than in HCs.
We show in this study that cholesterol profiles, apolipoproteins, and amino acids could function as a potential noninvasive test to screen for NAFLD or even NASH in larger populations. However, few differences in cholesterol profiles were identified between the NAFL and NASH groups, indicating similar cardiovascular risk profiles