Functional beta-cells derived from umbilical cord blood mesenchymal stem cells for curing rats with streptozotocin-induced diabetes mellitus

INTRODUCTIONThis study aimed to investigate the therapeutic response to injected human umbilical cord blood mesenchymal stem cells (UCBMSCs) among albino rats with streptozotocin (STZ)-induced diabetes mellitus.METHODSControl group (GI; n = 25) rats were fed with standard rat diet. Rats with STZ-induced diabetes mellitus without (GII; n = 25) and with (GIII; n = 25) differentiated human UCBMSCs implantation were the test groups. Rats were sacrificed in Week 11 following implantation. Liver biopsies were sectioned and stained in order to highlight both the presence and function of impregnated cells in the liver tissue.RESULTSHaematoxylin and eosin-stained sections in GI and GII rats showed normal liver architecture while GIII rats showed presence of cell clusters inside the liver tissue and around the central veins. Cell clusters with blue cytoplasm were present in sections in GIII rats but absent in GI and GII rats, indicating the presence of injected differentiated human UCBMSCs. The anti-human insulin immunostaining of GIII rats showed clusters of cells within the liver parenchyma and around central veins, indicating that these cells were active and secreting insulin.CONCLUSIONUCBMSCs are proficient in differentiating into insulin-producing cells in vivo under specific conditions and, when transplanted into the liver of albino rats with STZ-induced diabetes mellitus, were able to secrete insulin and partially control the status of diabetes mellitus in rats.     

Alignment of 3-dimensional cardiac structures in O-15-labeled water PET emission images with mutual information.

BACKGROUND: The aim of this study was to develop a method to correct the heart position between two oxygen 15-labeled water cardiac positron emission tomography (PET) image sets to be able to use the equivalent regions of interest for the quantification of the perfusion values in the same myocardial segments. METHODS AND RESULTS: Independent component analysis was applied to the dynamic image sets (simulated phantom and 6 rest-pharmacologic stress and 10 rest-rest image sets of healthy female volunteers) acquired at different time points to separate the cardiac structures (ventricles and myocardium). The separated component images from independent component analysis from the 2 studies of the same individual were aligned with a normalized mutual information-based registration method. The alignment parameters were applied to position the regions of interest in the floating image sets for calculation of the myocardial blood flow values. In the rest case the mean myocardial blood flow value was 0.76 +/- 0.12 mL x g(-1) x min(-1) for the manual method and 0.79 +/- 0.10 mL x g(-1) x min(-1) for the proposed method (by use of the right ventricle component in the alignment), and in the stress case these values were 3.39 +/- 0.70 mL x g(-1) x min(-1) and 4.01 +/- 0.71 mL x g(-1) x min(-1), respectively. No statistically significant difference was found between the methods. CONCLUSION: In the tests with the phantom and patient images the alignment of cardiac structures was shown to be successful. The alignment could be done without the use of information from the myocardial compartment.     

Use of plant- and period-specific job-exposure matrices in studies on occupational cancer

Job-exposure matrices were constructed and applied in the estimation of past exposures in a case-referent study nested within a cohort of Finnish woodworkers. The objective was to avoid bias in the risk estimates because of a misclassification of exposures. The matrices were constructed separately for each plant under study and each calendar year of follow-up. The level of exposure was incorporated in the matrices, since rather comprehensive data on exposures were available. The individual work histories were converted to exposure histories by a computer program which calculated several exposure indicators (eg, level and dose, with and without allowance for a latency period). The comparison between several indicators was thought to provide additional information for the final evaluation of results. The use of the plant- and period-specific job exposure matrices may be considered in cohort and nested case-referent studies on occupational hazards as an alternative to other procedures used in the estimation of exposures. Specific matrices may find broader applicability along with the increasing availability of detailed hygienic data.     

Expression of c-erbB-2 protein in keratinocytes of oral mucosal lichen planus and subsequent squamous cell carcinoma

Oral mucosal lichen planus (OMLP) is a well recognized mucosal disease with unknown etiology. Considerable controversy exists as to whether OMLP is intrinsically premalignant, or if the disorder facilitates the development of oral mucosal squamous cell carcinoma (OMSCC) by external factors. The aim of the present study was to investigate the expression of c-erbB-2 protein in the keratinocytes of initial biopsies of oral mucosal disorders diagnosed as OMLP with no evidence of epithelial dysplasia. and to compare the results with the expression of c-erbB-2 protein in subsequent biopsies obtained from the same patients. These results were compared with the findings from control groups (patients with dysplasia with no evidence of OMLP, patients with OMSCC with no evidence of OMLP and normal oral mucosa). The expression of the c-erbB-2 protein was evaluated by immunohistochemical staining of the gene product with the avidin-biotin-complex method using paraffin-embedded tissue sections. Five of the initial biopsies from patients with OMLP expressed the c-erhB-2 protein and one did not. None of the OMLP cases that subsequently showed evidence of dysplasia expressed the c-erhB-2 protein, and of the three OMSCC specimens from the patients with OMLP. two were negative and one expressed c-erbB-2 protein. The specimens from the control groups all expressed the c-erhB-2 protein. The results indicated the probability of the absence of c-erbB-2 staining being an indication of a potential for neoplastic transformation in OMLP with dysplastic changes.     

Mobility and percussion sound of healthy upper incisors and canines.

In order to evaluate the correlation between mobility and percussion sound, 126 upper incisors and canines in 21 student volunteers were measured by means of the Periotest (Siemens), by evaluating the percussion sound subjectively and by analyzing its spectrum. The attenuation time and frequency of the sound were measured for each tooth. A logical mobility and percussion sound existed in accordance with the sizes of the teeth. Spearman correlation coefficients close to 1.00 were noted in individual cases between the Periotest and the three other tests describing the percussion sounds.     

Contribution of cytoplasmic polypeptides to the 1H NMR spectrum of developing rat cerebral cortex.

In the present study the contribution of cytoplasmic polypeptides thymosins beta 4 and beta 10 to the 1H NMR spectrum during the maturation of the rat cerebral cortex was assessed. In the proton spectrum intense broad peaks at 0.9, 1.22, and 1.40 ppm from thymosins decreased in size relative to the signal at 2.02 ppm in parallel to the reciprocal increase in the concentration of N-acetyl aspartate. Levels of thymosins beta 4 and beta 10 were under developmental regulation. It is concluded that peaks from thymosins may provide extended information for an NMR spectroscopist and thus they have to be taken into account in the interpretation of the newborn cerebral 1H NMR spectrum.     

Ca2+-dependent and Ca2+-independent glutamate release, energy status and cytosolic free Ca2+ concentration in isolated nerve terminals following metabolic inhibition: possible relevance to hypoglycaemia and anoxia

Hypoglycaemia and anoxia both cause massive release of glutamate from the brain in vivo, and the nature of this release was investigated using guinea-pig cerebral-cortical synaptosomes and iodoacetate and rotenone to simulate the energetic consequences of these conditions. Glutamate release (by continuous fluorimetry), cytoplasmic free Ca2+ (by fura-2), membrane potentials, ATP, ADP and creatine phosphate were determined in parallel, following the addition of iodoacetate or rotenone, alone or in combination. Ca2+-dependent glutamate release had a high energy requirement which could only be satisfied by aerobic glycolysis. Respiration using endogenous substrates, or anaerobic glycolysis following rotenone, caused a progressive inhibition of Ca2+-dependent release, correlating with a decline in the total ATP/ADP ratio and creatine phosphate. With rotenone, an increase in Ca2+-independent glutamate release was observed, correlating with a decline in plasma membrane potential. Only a slight increase in free Ca2+ was seen. Rotenone plus iodoacetate caused an almost immediate collapse of ATP/ADP ratio and a parallel loss of Ca2+-dependent glutamate release before free Ca2+ had risen to a level sufficient for exocytosis. In contrast, Ca2+-independent glutamate release increased. The Ca2+-dependent release of L-glutamate had the characteristics of an exocytotic transmitter release mechanism, being energy-dependent and triggered by elevated cytoplasmic free Ca2+ concentration. A distinct Ca2+-independent release of cytoplasmic glutamate occurred by reversal of the Na+-coupled uptake carrier, which was accelerated by a decline in the Na+ gradient. It is concluded that the Ca2+-independent release of cytoplasmic glutamate may make the major contribution to the excitotoxic release of glutamate in hypoglycaemic and anoxic conditions.     

Mycobacterium malmoense-specific nested PCR based on a conserved sequence detected in random amplified polymorphic DNA fingerprints

Mycobacterium malmoense is an opportunistic human pathogen of increasing clinical importance. Since it is difficult to detect and identify the organism by conventional techniques, it was decided to seek a nucleic acid amplification method specific for M. malmoense. The method was based on detection of a conserved band in random amplified polymorphic DNA (RAPD) fingerprints of 45 M. malmoense strains. This band was a 1,046-bp product which was proven to be M. malmoense specific in dot blot hybridization analysis with a panel of mycobacterial strains belonging to 39 other species. The fragment was sequenced, and oligonucleotide primers were synthesized to evaluate the specificity of the PCR. Two primer pairs were found to be specific and sensitive in the nested PCR that was developed. All 49 M. malmoense strains analyzed produced a PCR product of the expected size. In contrast, no strains belonging to the other mycobacterial species tested produced amplicons with these primers under specified reaction conditions. The results of the electrophoresis were confirmed by the hybridization with the M. malmoense-specific oligonucleotide probe. This method could be applied to the analysis of clinical or environmental samples, permitting the rapid detection of M. malmoense.