Multi-modal brain magnetic resonance imaging database covering marmosets with a wide age range.

Magnetic resonance imaging (MRI) is a non-invasive neuroimaging technique that is useful for identifying normal developmental and aging processes and for data sharing. Marmosets have a relatively shorter life expectancy than other primates, including humans, because they grow and age faster. Therefore, the common marmoset model is effective in aging research. The current study investigated the aging process of the marmoset brain and provided an open MRI database of marmosets across a wide age range. The Brain/MINDS Marmoset Brain MRI Dataset contains brain MRI information from 216 marmosets ranging in age from 1 and 10 years. At the time of its release, it is the largest public dataset in the world. It also includes multi-contrast MRI images. In addition, 91 of 216 animals have corresponding high-resolution ex vivo MRI datasets. Our MRI database, available at the Brain/MINDS Data Portal, might help to understand the effects of various factors, such as age, sex, body size, and fixation, on the brain. It can also contribute to and accelerate brain science studies worldwide.

Food Additives (Hypochlorous Acid Water, Sodium Metabisulfite, and Sodium Sulfite) Strongly Affect the Chemical and Biological Properties of Vitamin B12 in Aqueous Solution.

Food additives, such as hypochlorous acid water, sodium metabisulfite, and sodium sulfite, strongly affect the chemical and biological properties of vitamin B12 (cyanocobalamin) in aqueous solution. When cyanocobalamin (10 µmol/L) was treated with these compounds, hypochlorous acid water (an effective chlorine concentration of 30 ppm) rapidly reacted with cyanocobalamin. The maximum absorptions at 361 and 550 nm completely disappeared by 1 h, and vitamin B12 activity was lost. There were no significant changes observed in the absorption spectra of cyanocobalamin for 0.01% (w/v) sodium metabisulfite; however, a small amount of the reaction product was formed within 48 h, which was subsequently identified as sulfitocobalamin through high-performance liquid chromatography. Similar results were shown for sodium sulfite. The effects of these food additives on the vitamin B12 content of red shrimp and beef meats were determined, revealing no significant difference in vitamin B12 content of shrimp and beef meats with or without the treatment even in hypochlorous acid water. The results suggest that these food additives could not react with food vitamin B12 in food, as most of this vitamin present in food is its protein-bound form rather than the free form.

Cooperative Regulation of the Mucosal Mast Cell-Specific Protease Genes Mcpt1 and Mcpt2 by GATA and Smad Transcription Factors.

Mouse mast cell proteases (mMCP)-1 and -2 are specifically expressed in mucosal mast cells (MCs). However, the transcriptional regulation mechanism of the Mcpt1 and Mcpt2 genes induced in mucosal MCs is largely unknown. In the current study, we found that TGF-ß stimulation drastically induced upregulation of Mcpt1 and Mcpt2 mRNA in mouse bone marrow-derived MCs (BMMCs). TGF-ß-induced expression of Mcpt1 and Mcpt2 was markedly suppressed by transfection with small interfering RNA targeting Smad2 or Smad4 and moderately reduced by Smad3 small interfering RNA. We next examined the roles of the hematopoietic cell-specific transcription factors GATA1 and GATA2 in the expression of Mcpt1 and Mcpt2 and demonstrated that knockdown of GATA1 and GATA2 reduced the mRNA levels of Mcpt1 and Mcpt2 in BMMCs. The recruitment of GATA2 and acetylation of histone H4 of the highly conserved GATA-Smad motifs, which were localized in the distal regions of the Mcpt1 and Mcpt2 genes, were markedly increased by TGF-ß stimulation, whereas the level of GATA2 binding to the proximal GATA motif was not affected by TGF-ß. A reporter assay showed that TGF-ß stimulation upregulated GATA2-mediated transactivation activity in a GATA-Smad motif-dependent manner. We also observed that GATA2 and Smad4 interacted in TGF-ß-stimulated BMMCs via immunoprecipitation and Western blotting analysis. Taken together, these results demonstrate that TGF-ß induced mMCP-1 and -2 expression by accelerating the recruitment of GATA2 to the proximal regions of the Mcpt1 and Mcpt2 genes in mucosal MCs.

Urinary trimethyl tin reflects blood trimethyl tin in workers recycling organotins.

AIM: Our recent case report of organotin intoxication showed higher ratio of urinary trimethyl tin (TMT) to dimethyl tin (DMT) than those of the previous cases exposed to only DMT, suggesting co-exposure to DMT and TMT occurred. The present study investigated how urinary TMT and DMT reflect blood TMT and DMT, respectively, to evaluate them as biomarkers for TMT/DMT exposure. METHODS: DMT and TMT from blood collected at different time points from three patients intoxicated with organotins were measured with HPLC-ICP/MS. Previously published data of urinary DMT and TMT were used for comparison. Regression analyses were conducted with dependent variable of blood DMT and TMT and independent variable of urinary DMT and TMT, respectively. Multiple regression analysis with dummy variables of individual was also conducted. RESULTS: Regression analysis did not show significant relation of urinary TMT to blood TMT or relation of urinary DMT to blood DMT, although the former was marginal. Multiple regression analysis showed significantly positive relation of urinary TMT to blood TMT. CONCLUSIONS: The study shows that urinary TMT reflects blood TMT. In co-exposure to TMT and DMT, urinary TMT can be an internal exposure marker of TMT, which might be not only derived from external exposure to TMT but also converted from DMT in human body.

A sialo-oligosaccharide-rich mucin-like molecule specifically detected in the submandibular glands of aged mice.

OBJECTIVES: Mucins are heavily glycosylated large glycoproteins produced in the salivary glands that contribute to salivary viscosity. This study aimed to characterize age-related changes in mucin production in mouse submandibular salivary gland (SMG). METHODS: The paraffin sections of the SMGs of the young and aged mice were stained with HE or Alcian blue (AB). SMGs mucins derived from the young and aged mice were separated using supported molecular matrix electrophoresis (SMME). After SMME, the membranes were stained with AB and subsequent glycan analysis or subjected to immunoblotting. The expression of 18 mucin genes and 4 sialyltransferase genes in the young and aged SMGs were determined by qPCR. The neuraminidase activity in the SMG homogenates was determined using Neuraminidase Assay Kit. RESULTS: The mouse SMG is more strongly stained by AB with increasing age. On SMME, a characteristic band not found in the young SMG is detected in aged SMG. Based on migration position and the MALDI MS, the band that appeared specifically with aging was determined to be acidic mucin. Additionally, most glycans of this acidic mucin were sialo-oligosaccharides. Furthermore, there was an increase in the expression of sialyltransferase genes ST6GalNAc I and ST6GalNAc II, but not a decrease in neuraminidase activity, in the SMG of aged mice. CONCLUSION: A sialomucin or sialylated mucin-like molecule not found in the SMGs of young WT mice is expressed in aged WT mice. The increase in the sialo-oligosaccharide content in this aging-associated molecule may be attributed to the increased expression of the sialyltransferase genes.

Magnetic resonance imaging of leukoencephalopathy in amnestic workers exposed to organotin.

We report the clinical and neuroimaging findings of 4 men who worked in the production of inorganic metal tin ingot from organotin scrap who presented with similar episodes of reversible amnesia. T2-weighted-fluid-attenuated inversion recovery magnetic resonance imaging (FLAIR MRI) scans in 3 of the patients showed symmetric hyperintensity in the frontoparietal periventricular white matter and the corpus callosum, and reduced apparent diffusion coefficients (ADCs) based on diffusion weighted imaging (DWI). One patient had symmetric faint hyperintensity in the parietal periventricular white matter only in the FLAIR images. The patients had elevated urinary levels of dimethyltin (DMT) and trimethyltin (TMT), but these concentrations decreased following cessation of exposure. Triethyltin, however, was not detected in urine. We diagnosed the present cases with organotin intoxication based on 5 lines of evidence. First, all patients were workers in the same tin-processing industry, complained of similar clinical symptoms, and had similar neuroimaging results. Second, the clinical features are compatible with a diagnosis of organotin encephalopathy. Third, all 4 workers were exposed to organotin for several days, and had high urinary concentrations of DMT and TMT. Fourth, the clinical features and brain MRI results ruled out other cerebral diseases. Fifth, MRI findings support a diagnosis of organotin encephalopathy.

Switching from Twice-Daily Basal Insulin Injections to Once-Daily Insulin Degludec Injection for Basal-Bolus Insulin Regimen in Japanese Patients with Type 1 Diabetes: A Pilot Study.

The aim of this study was to investigate the efficacy of insulin degludec used for basal-bolus insulin regimen after switching from twice-daily basal insulin in Japanese patients with type 1 diabetes mellitus. The subjects were 22 type 1 diabetes patients treated with basal-bolus insulin regimen with twice-daily basal insulin. Basal insulin was switched to once-daily injection of insulin degludec with 10% dose reduction. HbA1c and fasting plasma glucose (FPG) were measured before and 12 weeks after switching. The frequency of hypoglycemic episodes, standard deviation (SD) of blood glucose, and mean of daily difference (MODD) were evaluated by continuous glucose monitoring (CGM) before and 4 weeks after switching. HbA1c and FPG before and 12 weeks after switching were comparable (HbA1c 8.5 ± 1.4 versus 8.7 ± 1.6%, P = 0.28; FPG 203.2 ± 81.2 versus 206.5 ± 122.4 mg/dL, P = 0.91). The frequency of hypoglycemia during nighttime was not significantly different at 4 weeks after switching (14.4 ± 17.0 versus 11.1 ± 15.0%, P = 0.45). In addition, SD and MODD before and 4 weeks after switching were also comparable. In conclusion, glycemic control under once-daily insulin degludec injection was almost comparable to that under twice-daily basal insulin injections in Japanese type 1 diabetes patients. This study was registered with ID: UMIN000010474.

Dysregulation of the Bmi-1/p16(Ink4a) pathway provokes an aging-associated decline of submandibular gland function.

Bmi-1 prevents stem cell aging, at least partly, by blocking expression of the cyclin-dependent kinase inhibitor p16(Ink4a) . Therefore, dysregulation of the Bmi-1/p16(Ink4a) pathway is considered key to the loss of tissue homeostasis and development of associated degenerative diseases during aging. However, because Bmi-1 knockout (KO) mice die within 20 weeks after birth, it is difficult to determine exactly where and when dysregulation of the Bmi-1/p16(Ink4a) pathway occurs during aging in vivo. Using real-time in vivo imaging of p16(Ink4a) expression in Bmi-1-KO mice, we uncovered a novel function of the Bmi-1/p16(Ink4a) pathway in controlling homeostasis of the submandibular glands (SMGs), which secrete saliva into the oral cavity. This pathway is dysregulated during aging in vivo, leading to induction of p16(Ink4a) expression and subsequent declined SMG function. These findings will advance our understanding of the molecular mechanisms underlying the aging-related decline of SMG function and associated salivary gland hypofunction, which is particularly problematic among the elderly.

Endothelial cellular senescence is inhibited by liver X receptor activation with an additional mechanism for its atheroprotection in diabetes.

Senescence of vascular endothelial cells leads to endothelial dysfunction and contributes to the progression of atherosclerosis. Liver X receptors (LXRs) are nuclear receptors whose activation protects against atherosclerosis by transcriptional regulation of genes important in promoting cholesterol efflux and inhibiting inflammation. Here we found that LXR activation with specific ligands reduced the increase in senescence-associated (SA) ß-gal activity, a senescence marker, and reversed the decrease in telomerase activity, a replicative senescence marker, in human endothelial cells under high glucose. This effect of LXR activation was associated with reduced reactive oxygen species and increased endothelial NO synthase activity. A series of experiments that used siRNAs indicated that LXRß mediates the prevention of endothelial cellular senescence, and that sterol regulatory element binding protein-1, which was up-regulated as a direct LXRß target gene, may act as a brake of endothelial cellular senescence. Although oral administration of the LXR ligand led to severe fatty liver in diabetic rats, concomitant therapy with metformin avoided the development of hepatic steatosis. However, the preventive effect of the LXR ligand on SA ß-gal-stained cells in diabetic aortic endothelium was preserved even if metformin was coadministered. Taken together, our studies demonstrate that an additional mechanism, such as the regulation of endothelial cellular senescence, is related to the antiatherogenic properties of LXRs, and concomitant treatment with metformin may provide a clinically useful therapeutic strategy to alleviate an LXR activation-mediated adverse effects on liver triglyceride metabolism.

Development of taxon-specific sequences of common wheat for the detection of genetically modified wheat.

Qualitative and quantitative Polymerase Chain Reaction (PCR) systems aimed at the specific detection and quantification of common wheat DNA are described. Many countries have issued regulations to label foods that include genetically modified organisms (GMOs). PCR technology is widely recognized as a reliable and useful technique for the qualitative and quantitative detection of GMOs. Detection methods are needed to amplify a target GM gene, and the amplified results should be compared with those of the corresponding taxon-specific reference gene to obtain reliable results. This paper describes the development of a specific DNA sequence in the waxy-D1 gene for common wheat (Triticum aestivum L.) and the design of a specific primer pair and TaqMan probe on the waxy-D1 gene for PCR analysis. The primers amplified a product (Wx012) of 102 bp. It is indicated that the Wx012 DNA sequence is specific to common wheat, showing homogeneity in qualitative PCR results and very similar quantification accuracy along 19 distantly related common wheat varieties. In Southern blot and real-time PCR analyses, this sequence showed either a single or a low number of copy genes. In addition, by qualitative and quantitative PCR using wx012 primers and a wx012-T probe, the limits of detection of the common wheat genome were found to be about 15 copies, and the reproducibility was reliable. In consequence, the PCR system using wx012 primers and wx012-T probe is considered to be suitable for use as a common wheat-specific taxon-specific reference gene in DNA analyses, including GMO tests.

Applicability of the quantification of genetically modified organisms to foods processed from maize and soy.

The applicability of quantifying genetically modified (GM) maize and soy to processed foods was investigated using heat treatment processing models. The detection methods were based on real-time quantitative polymerase chain reaction (PCR) analysis. Ground seeds of insect resistant GM maize (MON810) and glyphosate tolerant Roundup Ready (RR) soy were dissolved in water and were heat treated by autoclaving for various time intervals. The calculated copy numbers of the recombinant and taxon specific deoxyribonucleic acid (DNA) sequences in the extracted DNA solution were found to decrease with time. This decrease was influenced by the PCR-amplified size. The conversion factor (Cf), which is the ratio of the recombinant DNA sequence to the taxon specific DNA sequence and is used as a constant number for calculating GM% at each event, tended to be stable when the sizes of PCR products of two DNA sequences were nearly equal. The results suggested that the size of the PCR product plays a key role in the quantification of GM organisms in processed foods. It is believed that the Cf of the endosperm (3n) is influenced by whether the GM originated from a paternal or maternal source. The embryos and endosperms were separated from the F1 generation seeds of five GM maize events, and their Cf values were measured. Both paternal and maternal GM events were identified. In these, the endosperm Cf was lower than that of the embryo, and the embryo Cf was lower than that of the endosperm. These results demonstrate the difficulties encountered in the determination of GM% in maize grains (F2 generation) and in processed foods from maize and soy.

Distinct conformation-mediated functions of an active site loop in the catalytic reactions of NAD-dependent D-lactate dehydrogenase and formate dehydrogenase.

The three-dimensional structures of NAD-dependent D-lactate dehydrogenase (D-LDH) and formate dehydrogenase (FDH), which resemble each other, imply that the two enzymes commonly employ certain main chain atoms, which are located on corresponding loop structures in the active sites of the two enzymes, for their respective catalytic functions. These active site loops adopt different conformations in the two enzymes, a difference likely attributable to hydrogen bonds with Asn97 and Glu141, which are also located at equivalent positions in D-LDH and FDH, respectively. X-ray crystallography at 2.4-A resolution revealed that replacement of Asn97 with Asp did not markedly change the overall protein structure but markedly perturbed the conformation of the active site loop in Lactobacillus pentosus D-LDH. The Asn97-->Asp mutant D-LDH exhibited virtually the same k(cat), but about 70-fold higher K(M) value for pyruvate than the wild-type enzyme. For Paracoccus sp. 12-A FDH, in contrast, replacement of Glu141 with Gln and Asn induced only 5.5- and 4.3-fold increases in the K(M) value, but 110 and 590-fold decreases in the k(cat) values for formate, respectively. Furthermore, these mutant FDHs, particularly the Glu141-->Asn enzyme, exhibited markedly enhanced catalytic activity for glyoxylate reduction, indicating that FDH is converted to a 2-hydroxy-acid dehydrogenase on the replacement of Glu141. These results indicate that the active site loops play different roles in the catalytic reactions of D-LDH and FDH, stabilization of substrate binding and promotion of hydrogen transfer, respectively, and that Asn97 and Glu141, which stabilize suitable loop conformations, are essential elements for proper loop functioning.