Apoptotic potential of the concentrated effective microorganism fermentation extract on human cancer cells

The effective microorganism fermentation extract (EM-X, the first generation) was claimed to possess strong anti-oxidation property. On the other hand, we have shown that the second generation of the effective microorganism fermentation extract (EM-X2) possessed growth inhibition on human cancer cells involving MDA-MB231 breast cancer and K-562 chronic myelogenous leukaemia cells. Elevation of super oxide dismutase activity from EM-X2 treated cancer cell extract was observed. However, the possible anti-cancer activity of the first generation of the EM-X was not reported. Here we demonstrate that the concentrated form of the EM-X from its original fluid also possess antiproliferation ability together with induction of apoptosis on the human cancer cell lines including Hep3B hepatocellular carcinoma (HCC) and KG1a acute myelogenous leukaemia (AML). Similar effect could also be demonstrated on primary cultured bone marrow samples isolated from patients with AML. Morphological inspection revealed that common apoptotic feature was found on these concentrated EM-X treated cancer cells. Both the anchorage-dependent clonogenicity assay on Hep3B HCC and methyl-cellulose colony formation assay on KG1a cells and bone marrow cells from AML patients further revealed the ability of the concentrated EM-X on reducing their colony formation ability. Incubating KG1a with concentrated EM-X readily induced apoptosis as demonstrated by flow cytometric analysis. Interestingly, few growth inhibition effect of the concentrated EM-X was observed on both the SV40 transformed THLE-2 liver epithelial cells and primary cultured non-malignant haematological disordered bone marrow. Collectively, this concentrated EM-X is effective in inducing cell death and reducing the regeneration potential of both Hep3B HCC and KG1a AML cells in vitro.     

Pro-oxidative effects of tea and polyphenols, epigallocatechin-3-gallate and epigallocatechin, on G6PD-deficient erythrocytes in vitro

Glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects are vulnerable to chemical-induced hemolysis if exposed to oxidative agents. Recent studies reported that green tea and its constituents might act as pro-oxidants. Our objective was to investigate effects of tea and its polyphenolic components on the oxidative status of human G6PD-deficient erythrocytes. Erythrocytes of G6PD-deficient (n = 8) and normal (n = 8) subjects were incubated with water extracts of 3 types of tea samples (black tea, green tea and decaffeinated green tea extract) and 6 polyphenols. The resulting levels of reduced glutathione (GSH) and glutathione disulphide (GSSG), methemoglobin and plasma hemoglobin were quantified by HPLC and biochemical assays. The tea extracts significantly reduced GSH and increased GSSG levels in G6PD-deficient erythrocytes in a dose-dependent manner (0.5-10 mg/ml), but not in normal erythrocytes. Similar dose-dependent responses to (-)-epigallocatechin (EGC) and (-)-epigallocatechin-3-gallate (EGCG), but not to the other polyphenols, were observed. In G6PD-deficient cells, GSH was reduced by 43.3% (EGC at 0.05 mg/ml) and 33.3% (EGCG at 0.5 mg/ml), compared with pre-challenged levels. The concentration of methemoglobin was increased significantly when challenged with tea extracts, and EGC. Plasma hemoglobin levels were higher in G6PD-deficient samples after exposure to tea extracts, EGCG, EGC and gallic acid, compared with those in normal blood. Tea extracts and polyphenols significantly altered the oxidative status of G6PD-deficient erythrocytes in vitro as demonstrated by the decrease of GSH, and increased GSSG, methemoglobin and plasma hemoglobin. Our data caution against the excessive consumption of concentrated tea polyphenolic products by G6PD-deficient subjects.     

Antiangiogenic activity of a concentrated effective microorganism fermentation extract

We have previously demonstrated the possible growth inhibitory activity of both first generation of the effective microorganism fermentation extract (EM-X) as well as the second generation (EM-X2) on cancer cell lines in vitro. The possible anti-angiogenic potential of EM-X has not been reported. Herein we show that using the concentrated EM-X, the growth of human umbilical cord endothelial cells (HUCE) was significantly inhibited in vitro. Enzyme linked immunosorbent assay suggested that the concentrated EM-X is able to reduce the level of vascular endothelial growth factor (VEGF) from Hep3B hepatocellular carcinoma (HCC) cells. The conditioned culture medium obtained from the concentrated EM-X incubated Hep3B HCC cells possessed significant antiproliferative effect on the HUCE cells. Moreover, in vivo chick chorioallantoic membrane assay further demonstrated that the concentrated EM-X is able to greatly inhibit the basic fibroblast growth factor induced angiogenesis from chick embryo experiment. We speculate that the anti-cancer potential of this concentrated EM-X involved growth inhibition on cancer cell and antiangiogenic effect on HUCE cells.     

Longitudinal MRI and cognitive change in healthy elderly

Cross-sectional studies of normal aging indicate an association between memory and hippocampal volume, and between executive functioning and subcortical-frontal circuits. Much less is known, however, about the relationship between longitudinal MRI changes and cognitive decline. The authors hypothesized that longitudinal change in memory would be best predicted by change in hippocampal volumes, whereas change in executive functioning would be best predicted by cortical atrophy and progression of MRI markers of cerebrovascular disease. For this study, 50 healthy elderly subjects underwent structural MRI and cognitive testing at baseline and again at follow-up, with a mean follow-up interval of 45 months. Volumetric MRI measures were hippocampus, cortical gray matter, white matter signal hyperintensity (WMSH), and lacunae. Neuropsychological measures were psychometrically robust composite scores of episodic memory (MEM) and executive functioning (EXEC). Hierarchical multiple regression indicated that a decrease in hippocampus was associated with a decline in MEM, whereas decreased cortical gray matter and increased WMSH were independently associated with a decline in EXEC. Results suggest that in normal aging, cognitive functioning declines as cortical gray matter and hippocampus decrease, and WMSH increases. The association between WMSH and EXEC further highlights the cognitive sequealae associated with cerebrovascular disease in normal elderly.     

Integrating spatial fuzzy clustering with level set methods for automated medical image segmentation

The performance of the level set segmentation is subject to appropriate initialization and optimal configuration of controlling parameters, which require substantial manual intervention. A new fuzzy level set algorithm is proposed in this paper to facilitate medical image segmentation. It is able to directly evolve from the initial segmentation by spatial fuzzy clustering. The controlling parameters of level set evolution are also estimated from the results of fuzzy clustering. Moreover the fuzzy level set algorithm is enhanced with locally regularized evolution. Such improvements facilitate level set manipulation and lead to more robust segmentation. Performance evaluation of the proposed algorithm was carried on medical images from different modalities. The results confirm its effectiveness for medical image segmentation.     

Shiga-toxigenic Escherichia coli detection in stool samples screened for viral gastroenteritis in Alberta, Canada

Shiga-toxigenic Escherichia coli (STEC) is an important cause of diarrheal disease. The most notorious STEC serotype is O157:H7, which is associated with hemorrhagic colitis and hemolytic-uremic syndrome (HUS). As a result, this serotype is routinely screened for in clinical microbiology laboratories. With the bias toward the identification of the O157 serogroup in routine diagnostic processes, non-O157 STEC has been largely underrepresented in the epidemiology of STEC infections. This diagnostic bias is further complicated by the fact that many non-O157 STEC infections cause nonspecific gastroenteritis symptoms reminiscent of enteric viral infections. In this study, real-time PCR was used to amplify Shiga toxin genetic determinants (stx(1) and stx(2)) from enriched stool samples that were initially submitted for the testing of enteric viruses in patients with suspected viral gastroenteritis between May and September of 2006, 2007, and 2008 (n = 2,702). Samples were submitted from the province of Alberta, Yukon, the Northwest Territories, and Nunavut, Canada. A total of 38 samples (1.4%) tested positive for Shiga toxin genes, and 15 isolates were cultured for further characterization. Several of the serotypes identified (O157:H7, O26:HNM, O26:H11, O103:H25, O121:H19, and O145:HNM) have been previously associated with outbreaks and HUS. This study outlines the importance of combining molecular methods with classical culture techniques to enhance the detection of emerging non-O157 as well as O157 serotypes in diarrheal stool samples. Furthermore, atypical diarrhea disease caused by non-O157 STEC can be routinely missed due to screening only for viral agents.     

Vestibular modulation of muscle sympathetic nerve activity by the utricle during sub-perceptual sinusoidal linear acceleration in humans

We assessed the capacity for the vestibular utricle to modulate muscle sympathetic nerve activity (MSNA) during sinusoidal linear acceleration at amplitudes extending from imperceptible to clearly perceptible. Subjects (n = 16) were seated in a sealed room, eliminating visual cues, mounted on a linear motor that could deliver peak sinusoidal accelerations of 30 mG in the antero-posterior direction. Subjects sat on a padded chair with their neck and head supported vertically, thereby minimizing somatosensory cues, facing the direction of motion in the anterior direction. Each block of sinusoidal motion was applied at a time unknown to subjects and in a random order of amplitudes (1.25, 2.5, 5, 10, 20 and 30 mG), at a constant frequency of 0.2 Hz. MSNA was recorded via tungsten microelectrodes inserted into muscle fascicles of the common peroneal nerve. Subjects used a linear potentiometer aligned to the axis of motion to indicate any perceived movement, which was compared with the accelerometer signal of actual room movement. On average, 67 % correct detection of movement did not occur until 6.5 mG, with correct knowledge of the direction of movement at ~10 mG. Cross-correlation analysis revealed potent sinusoidal modulation of MSNA even at accelerations subjects could not perceive (1.25–5 mG). The modulation index showed a positive linear increase with acceleration amplitude, such that the modulation was significantly higher (25.3 ± 3.7 %) at 30 mG than at 1.25 mG (15.5 ± 1.2 %). We conclude that selective activation of the vestibular utricle causes a pronounced modulation of MSNA, even at levels well below perceptual threshold, and provides further evidence in support of the importance of vestibulosympathetic reflexes in human cardiovascular control.     

Mirizzi综合征的误诊临床分析

目的 总结临床经验，提高Mirizzi综合征术前诊断率，提高疗效。方法 对1983年至2002年我院收治胆道手术病入中，术前误诊Mirzzi综合征15例，总结相关资料，做进一步总结分析。结果 15例术中诊断证实，手术试采用胆囊切除，胆囊大部切除加胆总管或肝总管探查，胆管修补，及胆肠吻合术。1例出现胆瘘，半月后自愈，1例因合并急性肾功能衰竭。结论 提高对Mirizzi综合征的认识，采用合理的诊断手段，术中精心操作，可减少Mirizzi误诊，提高疗效。     

Influence of electron-beam radiation on the hydrolytic degradation behaviour of poly(lactide-co-glycolide) (PLGA)

The purpose of this study is to examine the effect of electron-beam (e-beam) radiation on the hydrolytic degradation of poly(lactide-co-glycolide) (PLGA) films. PLGA films were irradiated and observed to undergo radiation-induced degradation through chain scission, as observed from a drop in its average molecular weight with radiation dose. Irradiated (5, 10 and 20 Mrad) and non-irradiated (0 Mrad) samples of PLGA were subsequently hydrolytically degraded in phosphate-buffered saline solution at 37.0 degrees C over a span of 12 weeks. It was observed that the natural logarithmic molecular weight (lnMn) of PLGA decreases linearly with hydrolytic degradation time. The rate of water uptake is higher for samples irradiated at higher radiation dose (e.g. 20 Mrad) and subsequently causing an earlier onset of mass loss. It is postulated that the increase in water uptake is due to the presence of more hydrophilic end groups, which results in the formation of microcavities because of an increase in osmotic pressure. A relationship between radiation dose and the rate of hydrolytic degradation of PLGA films, through its molecular weight was also established. This relationship allows a more accurate and precise control of the life span of PLGA through the use of e-beam radiation.