Protective effects of peroxiredoxin 6 overexpression on amyloid β-induced apoptosis in PC12 cells

Oxidative stress triggered by amyloid beta (Aβ) accumulation contributes substantially to the pathogenesis of Alzheimer's disease (AD). In the present study, we examined the involvement of the antioxidant activity of peroxiredoxin 6 (Prdx 6) in protecting against Aβ25-35-induced neurotoxicity in rat PC12 cells. Treatment of PC12 cells with Aβ25-35 resulted in a dose- and time-dependent cytotoxicity that was associated with increased accumulation of intracellular reactive oxygen species (ROS) and mitochondria-mediated apoptotic cell death, including activation of Caspase 3 and 9, inactivation of poly ADP-ribosyl polymerse (PARP), and dysregulation of Bcl-2 and Bax. This apoptotic signaling machinery was markedly attenuated in PC12 cells that overexpress wild-type Prdx 6, but not in cells that overexpress the C47S catalytic mutant of Prdx 6. This indicates that the peroxidase activity of Prdx 6 protects PC12 cells from Aβ25-35-induced neurotoxicity. The neuroprotective role of the antioxidant Prdx 6 suggests its therapeutic and/or prophylactic potential to slow the progression of AD and limit the extent of neuronal cell death caused by AD.

A strong magnetic field around the supermassive black hole at the centre of the Galaxy

Earth's nearest candidate supermassive black hole lies at the centre of the Milky Way. Its electromagnetic emission is thought to be powered by radiatively inefficient accretion of gas from its environment, which is a standard mode of energy supply for most galactic nuclei. X-ray measurements have already resolved a tenuous hot gas component from which the black hole can be fed. The magnetization of the gas, however, which is a crucial parameter determining the structure of the accretion flow, remains unknown. Strong magnetic fields can influence the dynamics of accretion, remove angular momentum from the infalling gas, expel matter through relativistic jets and lead to synchrotron emission such as that previously observed. Here we report multi-frequency radio measurements of a newly discovered pulsar close to the Galactic Centre and show that the pulsar's unusually large Faraday rotation (the rotation of the plane of polarization of the emission in the presence of an external magnetic field) indicates that there is a dynamically important magnetic field near the black hole. If this field is accreted down to the event horizon it provides enough magnetic flux to explain the observed emission--from radio to X-ray wavelengths--from the black hole.

Effect of DA-9701, a novel prokinetic agent, on stress-induced delayed gastric emptying and hormonal changes in rats

BACKGROUND

DA-9701 is a novel prokinetic agent formulated with Pharbitis Semen and Corydalis Tuber. This study aimed to evaluate the effect of DA-9701 on stress-induced delay in gastric emptying and changes in plasma adrenocorticotropic hormone and ghrelin levels in rats.

METHODS

Changes in gastric emptying in response to different durations of stress were evaluated. Gastric emptying was compared between the following groups: (i) nonstressed vehicle- or DA-9701-treated group, (ii) nonstressed vehicle- or mosapride-treated group, (iii) 2-h stressed vehicle- or DA-9701-treated group, and (iv) 2-h stressed vehicle- or mosapride-treated group. Water immersion restraint stress was used as the stressor. DA-9701 or mosapride at 3 mg kg(-1) was administered to the rats after subjecting them to 2-h stress, and then gastric emptying was measured using the phenol red method.

KEY RESULTS

Gastric emptying was significantly delayed in the 2-h stressed group compared with the nonstressed group. Mosapride administration resulted in significant recovery from the stress-induced delay in gastric emptying. Gastric emptying in the rats that underwent 2-h stress followed by DA-9701 administration was not significantly different from that in the nonstressed group. The plasma adrenocorticotropic hormone and active ghrelin levels in the 2-h stressed group were significantly higher than those in the nonstressed group. These increases were significantly inhibited by DA-9701.

CONCLUSIONS & INFERENCES

The administration of DA-9701 improved delayed gastric emptying and inhibited the hormonal changes induced by stress, suggesting that DA-9701 can be used as a gastroprokinetic agent for the treatment of delayed gastric emptying, particularly that associated with stress.

Effects of dietary supplementation of inosine monophosphate on growth performance, innate immunity and disease resistance of olive flounder (Paralichthys olivaceus)

This study was investigated to examine the effects of dietary inosine monophosphate (IMP) supplementation on growth performance, feed utilization, innate immunity, hematological parameters and disease resistance of juvenile olive flounder. Five experimental diets were formulated to contain IMP at levels of 0, 0.1, 0.2, 0.4 and 1.0%. All diets were maintained isonitrogenous (48% crude protein) and isocaloric (20.7 MJ/kg diet). Triplicate groups of olive flounder (initial body weight, 7.5 ± 0.02 g) were fed one of the experimental diets to apparent satiation (twice a day) for 14 weeks. Final body weight of fish fed 0.1-0.2% IMP were significantly higher than that of fish fed the 1.0% IMP. Groups of fish fed 0.2 or 0.4% IMP diet had significantly higher myeloperoxidase and lysozyme activities than fish fed the control diet. However, nitro-blue-tetrazolium and superoxide dismutase activities were not significantly different among all treatments. In the challenge test against Streptococcus iniae, cumulative mortality of fish fed IMP supplemented diets was significantly lower (15%, 4%, 4% and 9% for 0.1%, 0.2%, 0.4% and 1.0% IMP, respectively) than that of fish fed the control group (87%). The results suggest that IMP supplementation of 0.46-1.84 g into a kg of fish meal based diet (0.1-0.4% IMP product) can enhance innate immunity and disease resistance of olive flounder.

Comparison of Growth Performance and Whole-body Amino Acid Composition in Red Seabream (Pagrus major) Fed Free or Dipeptide Form of Phenylalanine

This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish (1.46±0.001 g) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.

Proteomic characterization of Kunitz trypsin inhibitor variants, Tia and Tib, in soybean [Glycine max (L.) Merrill]

The soybean Kunitz trypsin inhibitor (KTi) has several polymorphic variants. Of these, Tia and Tib, which differ by nine amino acids, are the two main types. In this study, differences in KTi proteome between Tia and Tib were investigated using three soybean cultivars and three mutant lines. Two cultivars, Baekwoon (BW) and Paldal (PD), and one mutant line, SW115-24, were Tia type, whereas one soybean cultivar, Suwon115 (SW115), and two mutant lines, BW-7-2 and PD-5-10, were Tib type. Protein from the six soybean lines was extracted and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), non-denaturing polyacrylamide gel electrophoresis (non-denaturing PAGE), and two-dimensional polyacrylamide gel electrophoresis (2-DE). By SDS-PAGE, there was no difference between soybean cultivars and mutant lines, except for SW115-24. Western blot analysis revealed that, in comparison with Tia, Tib type accumulated relatively low amounts of KTi. By non-denaturing PAGE, the three soybean lines of Tib type were characterized by slower mobility than the three soybean lines of Tia type. Zymography detected eight distinct zones of trypsin inhibitory activity among which Tia and Tib lacked the fifth and sixth zone, respectively. By two-dimensional native polyacrylamide gel electrophoresis (2-DN), the spots related to trypsin inhibitory activity showed different mobilities, whereas only one KTi (21.5 kDa) spot was resolved by 2-DE. By two-dimensional zymography (2-DZ), Tib showed a broader activity zone (pI 4-7) in comparison with Tia (pI 4-5). The results indicate that the genotypes with a different type of KTi present different proteomic profiles and trypsin inhibitory activities.

Efficacy of ramosetron in the treatment of male patients with irritable bowel syndrome with diarrhea: a multicenter, randomized clinical trial, compared with mebeverine

BACKGROUND

The 5-HT(3) receptor antagonists are known to be effective for the treatment of diarrhea-predominant irritable bowel syndrome (IBS), but not widely used yet. The aim of this study was to compare the efficacy and safety of ramosetron, a 5-HT(3) receptor antagonist, and mebeverine in male patients with IBS with diarrhea (IBS-D).

METHODS

This study was performed in a multicenter, randomized, open-label design. Data of 343 male patients with IBS-D who were randomized to either a 4-week treatment of ramosetron 5μg once daily or a 4-week treatment of mebeverine 135 mg three times daily were analyzed by the intent-to-treat analysis. The primary efficacy parameter was the proportion of patients with adequate relief of IBS symptoms at the last week of treatment. The secondary endpoints were changes in each symptom score and the safety profiles.

KEY RESULTS

The responder rates for global IBS symptoms, abdominal pain/discomfort and abnormal bowel habits in the ramosetron and mebeverine groups significantly increased during the treatment period. The severity scores of abdominal pain/discomfort and urgency, the stool form score, and the stool frequency in both treatment arms were significantly reduced, compared with the baselines. There were no significant differences in the responder rates (37%vs 38% on ITT analysis) and adverse event profiles between the ramosetron and mebeverine groups. Neither severe constipation nor ischemic colitis was reported by ramosetron-treated patients.

CONCLUSIONS & INFERENCES

Ramosetron 5μg once daily is as effective as mebeverine three times daily in male patients with IBS-D.

Prognostic factors for idiopathic pulmonary fibrosis: clinical, physiologic, pathologic, and molecular aspects

BACKGROUND

Previous studies identified clinical and physiologic factors of idiopathic pulmonary fibrosis (IPF) that are related to an increased risk of mortality. But there are few studies about histologic and molecular approach.

OBJECTIVE

We investigated whether the C-reactive protein (CRP), fibroblastic foci, phosphorylated Smad2/3 (p-Smad2/3), tumor growth factor-beta (TGF-beta), TGF-beta receptor II (TbetaRII), and the polymorphism of the TGF-beta1 codon 10 are associated with the progression of IPF patients.

DESIGN

Eighty-six IPF patients who underwent surgical lung biopsies were examined. For each patient, clinical and physiologic parameters were investigated, and we performed immunohistochemical staining for p-Smad2/3 and TbetaRII, and genotyping of the TGF-beta1 codon 10 polymorphism.

RESULTS

Age at diagnosis, gender, symptom duration, and smoking status did not show a significant association. However, the amount of smoking (p = 0.002), severe reduction in the percentages of predicted forced vital capacity (p = 0.013) and diffusion lung capacity of carbon monoxide (p = 0.023), CRP (p = 0.009) at diagnosis, and fibroblastic foci (p = 0.026) were associated with a poor prognosis. Cellularity, fibrosis, expression level of p-Smad2/3 and TbetaRII, and genotype of the TGF-beta1 codon 10 polymorphism did not have a statistically significant association with the prognosis.

CONCLUSION

This study confirmed the amount of smoking, abrupt decrease in follow-up pulmonary function parameters, fibroblastic foci, and increased levels of CRP concentration at diagnosis were significantly associated with poor survival. Larger studies are required to confirm all prognostic factors including CRP.

EHR/EMR: "Meaningful use," stimulus money, and the Serenity Prayer

Theologian Reinhold Niebuhr said, “God, grant me the serenity to accept the things I cannot change; courage to change the things I can; and wisdom to know the difference.”

Meaningful use of electronic health records in otolaryngology: recommendations from the American Academy of Otolaryngology--Head and Neck Surgery Medical Informatics Committee

Under the Health Information Technology for Economic and Clinical Health (HITECH) Act, passed as a part of the American Recovery and Reinvestment Act of 2009, the US Congress implemented new regulations to encourage the adoption of electronic health records (EHRs). The federal government will expend up to $27 billion in incentive payments to physicians and hospitals to increase adoption and implement "meaningful use" of EHRs. Otolaryngologists may receive as much as $44,000 under Medicare or $63,750 under Medicaid as part of this law. In July 2010, the US Department of Health and Human Services announced final rules to support "meaningful use." This commentary discusses recommendations from the American Academy of Otolaryngology--Head and Neck Surgery Medical Informatics Committee for implementing "meaningful use" of EHRs to improve safety, quality, and efficiency of patient care and receiving incentive payments as defined by these new regulations.

Rapid and simple detection of the invA gene in Salmonella spp. by isothermal target and probe amplification (iTPA)

AIMS

Salmonella spp. are an important cause of food-borne infections throughout world, and the availability of rapid and simple detection techniques is critical for the food industry. Salmonella enterica serovars Enteritidis and Typhimurium cause the majority of human gastroenteritis infections, and there are a reported 40,000 cases of salmonellosis in the United States each year.

METHODS AND RESULTS

A novel rapid and simple isothermal target and probe amplification (iTPA) assay that rapidly amplifies target DNA (Salmonella invA gene) using a FRET-based signal probe in an isothermal environment was developed for detection Salmonella spp. in pre-enriched food samples. The assay was able to specifically detect all of 10 Salmonella spp. strains without detecting 40 non-Salmonella strains. The detection limit was 4 x 10¹ CFU per assay. The iTPA assay detected at an initial inoculum level of <10 CFU in the pre-enriched food samples (egg yolk, chicken breast and peanut butter).

CONCLUSIONS

This detection system requires only a water bath and a fluorometer and has great potential for use as a hand-held device or point-of-care-testing diagnostics. The iTPA assay is sensitive and specific and has potential for rapid screening of Salmonella spp. by food industry.

Identification of Kunitz trypsin inhibitor mutations using SNAP markers in soybean mutant lines

The Kunitz trypsin inhibitor (KTi) in soybean has several polymorphic types that are controlled by multiple alleles, which behave in a co-dominant fashion. Of these, Tia and Tib, which differ by nine amino acids, are the predominant types. In order to develop a single nucleotide amplified polymorphism (SNAP) marker for the classification of the predominant KTi types, Tia and Tib, and evaluate KTi activities by differing KTi type total 451 soybean mutant lines (M(12)-M(16) generation) were incorporated in this study. Among 451 soybean mutants, 144 and 13 mutant lines showed decreased and increased trypsin inhibitor activity when compared with the original cultivars, respectively. To identify the KTi type, we designed a SNAP marker. Among 451 mutant lines from 12 soybean cultivars and landraces, 8 mutant lines derived from cvs. Baekwoon, Paldal and Suwon115 showed a change in KTi type when compared with the original cultivars using the SNAP marker. Five mutant lines in Suwon115 changed from Tib to Tia, while two mutant lines derived from cv. Baekwoon and one mutant line derived from cv. Paldal were changed from Tia to Tib. These changes of KTi types were confirmed by sequencing of the KTi genes and non-denaturing polyacrylamide gel electrophoresis of the KTi proteins. To identify the effect of KTi activity based on the change in KTi type, we measured the KTi activity using the three cultivars and eight mutant lines that showed changes in KTi type. Two mutant lines (BW-1 and 7-2) derived from cv. Baekwoon and one mutant line (PD-5-10) from cv. Paldal that changed from Tia to Tib showed lower activity than the original cultivar. In cv. Suwon115, five mutant lines that changed from Tib to Tia showed higher activity than the original cultivar. These results indicate that the designed SNAP marker was capable of identifying the KTi type and that Tia activity was higher than Tib activity in soybean.

Immune regulatory effects of simvastatin on regulatory T cell-mediated tumour immune tolerance

Statins are potent inhibitors of hydroxyl-3-methylglutaryl co-enzyme A (HMG-CoA) reductase, and have emerged as potential anti-cancer agents based on preclinical evidence. In particular, compelling evidence suggests that statins have a wide range of immunomodulatory properties. However, little is known about the role of statins in tumour immune tolerance. Tumour immune tolerance involves the production of immunosuppressive molecules, such as interleukin (IL)-10, transforming growth factor (TGF)-beta and indoleamine-2,3-dioxygenase (IDO) by tumours, which induce a regulatory T cell (T(reg)) response. In this study, we investigated the effect of simvastatin on the production of IL-10, TGF-beta and IDO production and the proliferation of T(regs) using several cancer cell lines, and Lewis lung cancer (3LL) cells-inoculated mouse tumour model. Simvastatin treatment resulted in a decrease in the number of cancer cells (3LL, A549 and NCI-H292). The production of the immune regulatory markers IL-10, TGF-beta in 3LL and NCI-H292 cells increased after treatment with simvastatin. The expression of IDO and forkhead box P3 (FoxP3) transcription factor was also increased in the presence of simvastatin. In a murine 3LL model, there were no significant differences in tumour growth rate between untreated and simvastatin-treated mice groups. Therefore, while simvastatin had an anti-proliferative effect, it also exhibited immune tolerance-promoting properties during tumour development. Thus, due to these opposing actions, simvastatin had no net effect on tumour growth.

Beta amyloid-independent role of amyloid precursor protein in generation and maintenance of dendritic spines

Synapse loss induced by amyloid beta (Abeta) is thought to be a primary contributor to cognitive decline in Alzheimer's disease. Abeta is generated by proteolysis of amyloid precursor protein (APP), a synaptic receptor whose physiological function remains unclear. In the present study, we investigated the role of APP in dendritic spine formation, which is known to be important for learning and memory. We found that overexpression of APP increased spine number, whereas knockdown of APP reduced spine density in cultured hippocampal neurons. This spine-promoting effect of APP required both the extracellular and intracellular domains of APP, and was accompanied by specific upregulation of the GluR2, but not the GluR1, subunit of AMPA receptors. In an in vivo experiment, we found that cortical layers II/III and hippocampal CA1 pyramidal neurons in 1 year-old APP-deficient mice had fewer and shorter dendritic spines than wild-type littermates. In contrast, transgenic mice overexpressing mutant APP exhibited increased spine density compared to control animals, though only at a young age prior to overaccumulation of soluble amyloid. Additionally, increased glutamate synthesis was observed in young APP transgenic brains, whereas glutamate levels were decreased and GABA levels were increased in APP-deficient mice. These results demonstrate that APP is important for promoting spine formation and is required for proper spine development.

Altered intestinal microbiota in irritable bowel syndrome

Recent studies have suggested that alterations in the composition of the intestinal microbiota may play an important role in irritable bowel syndrome (IBS) symptoms. However, an association between the composition of the intestinal microbiota and IBS symptoms has not been clearly demonstrated. In the current issue of the Journal, Tana et al. suggest that altered intestinal microbiota contributes to the symptoms of IBS through increased levels of organic acids. In fecal samples, IBS patients had significantly higher numbers of Veillonella and Lactobacillus than healthy controls. They also showed significantly higher levels of acetic acid and propionic acid. Furthermore, IBS patients with high acetic acid or propionic acid levels presented more severe symptoms, impaired quality of life and negative emotions. These results are in accordance with the concept that the gut microbiota influences the sensory, motor and immune system of the gut and interacts with higher brain centers. Small intestinal bacterial overgrowth observed in a subset of IBS patients describes quantitative changes in the small intestinal microbiota. Data on qualitative changes in the gut microbiota in IBS patients are lacking. Different members of gut bacteria may have different influence on gut function. The concepts identified here may lead to the development of novel therapeutic strategies for IBS using manipulation of the intestinal microbiota.

Effects of aerobic exercise training on cognitive function and cortical vascularity in monkeys

This study examined whether regular exercise training, at a level that would be recommended for middle-aged people interested in improving fitness could lead to improved cognitive performance and increased blood flow to the brain in another primate species. Adult female cynomolgus monkeys were trained to run on treadmills for 1 h a day, 5 days a week, for a 5 month period (n=16; 1.9+/-0.4 miles/day). A sedentary control group sat daily on immobile treadmills (n=8). Half of the runners had an additional sedentary period for 3 months at the end of the exercise period (n=8). In all groups, half of the monkeys were middle-aged (10-12 years old) and half were more mature (15-17 years old). Starting the fifth week of exercise training, monkeys underwent cognitive testing using the Wisconsin General Testing Apparatus (WGTA). Regardless of age, the exercising group learned to use the WGTA significantly faster (4.6+/-3.4 days) compared to controls (8.3+/-4.8 days; P=0.05). At the end of 5 months of running monkeys showed increased fitness, and the vascular volume fraction in the motor cortex in mature adult running monkeys was increased significantly compared to controls (P=0.029). However, increased vascular volume did not remain apparent after a 3-month sedentary period. These findings indicate that the level of exercise associated with improved fitness in middle-aged humans is sufficient to increase both the rate of learning and blood flow to the cerebral cortex, at least during the period of regular exercise.