Effects of vitamin E and selenium administration on transportation stress in pregnant dairy heifers.

We investigated the effects of road transportation and administration of the vitamin E and selenium (ESe) on circulating cortisol, haptoglobin, blood metabolites, oxidative biomarkers, white blood cell profiles, and behaviors in pregnant dairy heifers. Forty pregnant Holstein heifers were randomly assigned to one of 4 treatments: no transportation and no ESe administration, no transportation and ESe administration, transportation and no administration, and transportation and ESe administration. The ESe (70 IU/kg dry matter feed of dl-α-tocopheryl acetate and 0.3 mg/kg dry matter feed of sodium selenite) was orally delivered once a day from 7 d before transportation to 3 d after transportation. The heifers were transported in trucks designed for cattle transportation. Blood was collected 1 h before transportation, immediately after transportation (IAT), and at 6, 24, and 48 h after transportation. Behaviors were recorded using a video camera for 2 consecutive days after transportation. Transported/non-ESe-administered heifers had greater cortisol at IAT, haptoglobin at 6 and 24 h after transportation, total oxidative status at 6 h after transportation, and nonesterified fatty acid levels, white blood cell numbers, and neutrophil percentages at IAT and 6 h after transportation in the blood than nontransported heifers. Transported/non-ESe-administered heifers had lower total antioxidative status levels at 48 h after transportation and lymphocyte percentages at IAT and 6 h after transportation than nontransported heifers. Lying time was shorter in transported heifers than nontransported/non-ESe-administered heifers. Transported/ESe-administered heifers had lower cortisol, total oxidative status, nonesterified fatty acid levels at IAT, and haptoglobin concentrations at 6 and 24 h after transportation than transported/non-ESe-administered heifers. Transported/ESe-administered heifers had greater total antioxidative status levels at 48 h after transportation than transported/non-ESe-administered heifers. No ESe administration effects were observed for white blood cell number and neutrophil and lymphocyte percentages and lying time. In conclusion, road transportation caused temporary oxidative stress. Administrating ESe partially alleviated the stress, suggesting that ESe administration could be a viable strategy to reduce stress in transported pregnant heifers, providing a novel role of vitamin E and selenium for improving animal welfare.

Effects of genomic estimated breeding value and dietary energy to protein ratio on growth performance, carcass trait, and lipogenic gene expression in Hanwoo steer.

"Genome-based precision feeding" is a concept that involves the application of customised diets to different genetic groups of cattle. We investigated the effects of the genomic estimated breeding value (gEBV) and dietary energy to protein ratio (DEP) on growth performance, carcass traits, and lipogenic gene expression in Hanwoo (Korean cattle) steers. Forty-four Hanwoo steers (BW = 636 kg, age = 26.9 months) were genotyped using the Illumina Bovine 50 K BeadChip. The gEBV was calculated using genomic best linear unbiased prediction. Animals were separated into high gEBV of marbling score or low-gMS groups based on the upper and lower 50% groupings of the reference population, respectively. Animals were assigned to one of four groups in a 2 × 2 factorial arrangement: high gMS/high DEP (0.084 MJ/g), high gMS/low DEP (0.079 MJ/g), low gMS/high DEP, and low gMS/low DEP. Steers were fed concentrate with a high or low DEP for 31 weeks. The BW tended to be higher (0.05 < P < 0.1) in the high-gMS groups compared to the low-gMS groups at 0, 4, 8, 12, and 20 weeks. The average daily gain (ADG) tended to be lower (P = 0.08) in the high-gMS group than in the low-gMS group. Final BW and measured carcass weight (CW) were positively correlated with the gEBV of carcass weight (gCW). The DEP did not affect ADG. Neither the gMS nor the DEP affected the MS and beef quality grade. The intramuscular fat (IMF) content in the longissimus thoracis (LT) tended to be higher (P = 0.08) in the high-gMS groups than in the low-gMS groups. The mRNA levels of lipogenic acetyl-CoA carboxylase and fatty acid binding protein 4 genes in the LT were higher (P < 0.05) in the high-gMS group than in the low-gMS group. Overall, the IMF content tended to be affected by the gMS, and the genetic potential (i.e., gMS) was associated with the functional activity of lipogenic gene expression. The gCW was associated with the measured BW and CW. The results demonstrated that the gMS and the gCW may be used as early prediction indexes for meat quality and growth potential of beef cattle.

TRIENNIAL GROWTH AND DEVELOPMENT SYMPOSIUM: Molecular mechanisms related to bovine intramuscular fat deposition in the longissimus muscle.

The intramuscular fat (IMF) content of the LM, also known as marbling, is particularly important in determining the price of beef in Korea, Japan, and the United States. Deposition of IMF is influenced by both genetic (e.g., breed, gender, and genotype) and nongenetic factors (e.g., castration, nutrition, stressors, animal weight, and age). Castration of bulls markedly increases deposition of IMF, resulting in improved beef quality. Here, we present a comparative gene expression approach between bulls and steers. Transcriptomic and proteomic studies have demonstrated that the combined effects of increases in lipogenesis, fatty acid uptake, and fatty acid esterification and decreased lipolysis are associated with increased IMF deposition in the LM. Several peripheral tissues (LM, adipose tissues, and the liver) are involved in lipid metabolism. Therefore, understanding the significance of the tissue network in lipid metabolism is important. Here, we demonstrate that lipid metabolism in LM tissues is crucial for IMF deposition, whereas lipid metabolism in the liver plays only a minor role. Metabolism of body fat and IMF deposition in bovine species has similarities with these processes in metabolic diseases, such as obesity in humans and rodents. Extensive studies on metabolic diseases using epigenome modification (DNA methylation, histone modification, and microRNA), microbial metagenomics, and metabolomics have been performed in humans and rodents, and new findings have been reported using these technologies. The importance of applying "omics" fields (epigenomics, metagenomics, and metabolomics) to the study of IMF deposition in cattle is described. New information on the molecular mechanisms of IMF deposition may be used to design nutritional or genetic methods to manipulate IMF deposition and to modify fatty acid composition in beef cattle. Applying nutrigenomics could maximize the expression of genetic potential of economically important traits (e.g., marbling) in animals.

Effects of Ambient Temperature on Growth Performance, Blood Metabolites, and Immune Cell Populations in Korean Cattle Steers.

Exposure to cold may affect growth performance in accordance with the metabolic and immunological activities of animals. We evaluated whether ambient temperature affects growth performance, blood metabolites, and immune cell populations in Korean cattle. Eighteen Korean cattle steers with a mean age of 10 months and a mean weight of 277 kg were used. All steers were fed a growing stage-concentrate diet at a rate of 1.5% of body weight and Timothy hay ad libitum for 8 weeks. Experimental period 1 (P1) was for four weeks from March 7 to April 3 and period 2 (P2) was four weeks from April 4 to May 1. Mean (8.7°C) and minimum (1.0°C) indoor ambient temperatures during P1 were lower (p<0.001) than those (13.0°C and 6.2°C, respectively) during P2. Daily dry matter feed intake in both the concentrate diet and forage groups was higher (p<0.001) during P2 than P1. Average daily weight gain was higher (p<0.001) during P2 (1.38 kg/d) than P1 (1.13 kg/d). Feed efficiency during P2 was higher (p = 0.015) than P1. Blood was collected three times; on March 7, April 4, and May 2. Nonesterified fatty acids (NEFA) were higher on March 7 than April 4 and May 2. Blood cortisol, glucose, and triglyceride concentrations did not differ among months. Blood CD4+, CD8+, and CD4+CD25+ T cell percentages were higher, while CD8+CD25+ T cell percentage was lower, during the colder month of March than during May, suggesting that ambient temperature affects blood T cell populations. In conclusion, colder ambient temperature decreased growth and feed efficiency in Korean cattle steers. The higher circulating NEFA concentrations observed in March compared to April suggest that lipolysis may occur at colder ambient temperatures to generate heat and maintain body temperature, resulting in lower feed efficiency in March.

Time-resolved laser fluorescence spectroscopy of UO2(CO3)3(4-).

The objective of the present study is to examine the luminescence characteristics of UO2(CO3)3(4-) in detail using time-resolved laser fluorescence spectroscopy. The peak wavelengths and lifetime of UO2(CO3)3(4-) were determined at room temperature using the two excitation laser wavelengths of 266 and 448 nm. The peak wavelengths in the luminescence spectrum exhibited hypsochromic shifts compared with those of UO2(2+). The lifetime determined from several samples containing various uranium concentrations was 8.9 ± 0.8 ns. Explanations for the hindrance to the observation of the luminescence spectrum of UO2(CO3)3(4-) in previous investigations are discussed. The representative experimental parameters, which might interrupt the measurement of weak luminescence, are the insertion delay time of the detection device, the overlapped luminescence of the background materials and the primary inner filter effect in the sample solution.

Effects of Dietary Restriction on the Expression of Lipid Metabolism and Growth Hormone Signaling Genes in the Longissimus dorsi Muscle of Korean Cattle Steers.

This study determined the effects of dietary restriction on growth and the expression of lipid metabolism and growth hormone signaling genes in the longissimus dorsi muscle (LM) of Korean cattle. Thirty-one Korean cattle steers (average age 10.5 months) were allocated to normal (N; n = 16) or dietary restriction (DR; n = 15) groups. The feeding trial consisted of two stages: for the 8-month growing period, the DR group was fed 80% of the food intake of the normal diet, and for the 6-month growth-finishing period, the DR group was fed a DR total mixed ration with 78.4% of the crude protein and 64% of the net energy for gain of the normal diet. The LM was biopsied 5 months (period 1 [P1] at 15.5 months of age) and 14 months (period 2 [P2] at 24.5 months of age) after the start of feeding. The mRNA levels were determined using real-time polymerase chain reaction. Body weight, daily feed intake, average daily gain, and feed efficiency were lower in the DR group compared with the normal group at both P1 and P2. At P1, the lipogenic fatty acid synthase (FASN) mRNA levels were lower (p<0.05) in the DR group compared with the normal group. The DR group tended (p = 0.06) to have higher of levels of growth hormone receptor (GHR) mRNA than the normal group. At P2, the DR group tended to have lower (p = 0.06) androgen receptor (AR) mRNA levels than the normal group. In conclusion, our results demonstrate that dietary restriction partially decreases the transcription of lipogenic FASN and growth hormone signaling AR genes, but increases transcription of the GHR gene. These changes in gene transcription might affect body fat accumulation and the growth of the animals.

Seasonal variation in carcass characteristics of korean cattle steers.

Climate temperature affects animal production. This study was conducted to evaluate whether climatic conditions affect beef carcass characteristics of Korean cattle steers. The monthly carcass characteristics of Korean cattle steers (n = 2,182,415) for 8 yr (2006 through 2013) were collected from the Korean Institute for Animal Products Quality Evaluation. Daily climate temperature (CT) and relative humidity (RH) data were collected from the Korean Meteorological Administration. Weather conditions in South Korea during summer were hot and humid, with a maximum temperature of 28.4°C and a maximum RH of 91.4%. The temperature-humidity index (THI), calculated based on CT and RH, ranges from 73 to 80 during summer. Winter in South Korea was cold, with a minimum temperature of -4.0°C and a wind-chill temperature of -6.2°C. Both marbling score (MS) and quality grade (QG) of Korean cattle steer carcasses were generally best (p<0.05) in autumn and worst in spring. A correlation analysis showed that MS and QG frequencies were not associated (p>0.05) with CT. Yield grade (YG) of Korean cattle steer carcasses was lowest (p<0.05) in winter (November to January) and highest in spring and summer (May to September). A correlation analysis revealed that YG frequency was strongly correlated (r≥0.71; p<0.01) with CT and THI values. The rib eye area, a positive YG parameter, was not associated with CT. Backfat thickness (BT), a negative YG factor, was highest in winter (November and December). The BT was strongly negatively correlated (r≤-0.74; p<0.01) with CTs. Therefore, the poor YG during winter is likely due in part to the high BT. In conclusion, YG in Korean cattle steer carcasses was worst in winter. QGs were not associated with winter or summer climatic conditions.

Association of DNA Methylation Levels with Tissue-specific Expression of Adipogenic and Lipogenic Genes in Longissimus dorsi Muscle of Korean Cattle.

Epigenetic factors, such as DNA methylation status, may regulate adipogenesis and lipogenesis, thus affecting intramuscular fat (IMF) deposition in longissimus dorsi muscle (LM) of beef cattle. In Korean cattle steers, the LM consists mainly of muscle tissue. However, the LM tissue also contains IMF. We compared the gene expression levels between the IMF and muscle portions of the LM after tissue separation. Real-time polymerase chain reaction analysis showed that the mRNA levels of both adipogenic peroxisome proliferator-activated receptor gamma isoform 1 (PPARG1) and lipogenic fatty acid binding protein 4 (FABP4) were higher (p<0.01) in the IMF than in the muscle portion of the LM. We determined DNA methylation levels of regulatory regions of the PPARG1 and FABP4 genes by pyrosequencing of genomic DNA. DNA methylation levels of two of three CpG sites in the PPARG1 gene promoter region were lower (p<0.05) in the IMF than in the muscle portion of the LM. DNA methylation levels of all five CpG sites from the FABP4 gene promoter region were also lower (p<0.001) in the IMF than in the muscle portion. Thus, mRNA levels of both PPARG1 and FABP4 genes were inversely correlated with DNA methylation levels in regulatory regions of CpG sites of the corresponding gene. Our findings suggest that DNA methylation status regulates tissue-specific expression of adipogenic and lipogenic genes in the IMF and muscle portions of LM tissue in Korean cattle.

An intrauterine catch-up growth regimen increases food intake and post-natal growth in rats.

Nutritional conditions during the intrauterine stage are an important developmental programming factor that can affect the growth and metabolic status during foetal development and permanently alter the phenotypes of newborn offspring and adults. This study was performed to examine the effects of intrauterine catch-up growth (IUCG) on food intake, post-natal body growth and the metabolic status of offspring and growing rats. Control pregnant rats were fed ad libitum during the entire gestation period. For the IUCG regimen, pregnant rats were fed 50% of the food of the controls from pregnancy days 4 through 11 (8 days), followed by ad libitum feeding from pregnancy days 12 through parturition. The birth weight of offspring was not affected by the IUCG regimen. At weaning, offspring from each treatment group were assigned to two groups and given either a normal diet or high-fat diet (HFD) for 12 weeks until 103 days of age. In the normal diet group, the IUCG offspring showed a 9.0% increase (P < 0.05) in total food intake, were 11.2% heavier (p < 0.05) at 103 days of age and had an 11.0% greater (p < 0.05) daily weight gain compared with control offspring. The IUCG regimen did not affect body glucose and lipid metabolism. After exposure to the HFD, the IUCG regimen has not exacerbated metabolic disorders. In conclusion, our findings suggest that the IUCG nutritional regimen during pregnancy can increase the food intake and post-natal body growth of offspring without inducing metabolic disorders such as obesity and insulin resistance. The IUCG nutritional regimen might be used to improve the food intake and post-natal body growth of domestic animals.

Severe dietary lysine restriction affects growth and body composition and hepatic gene expression for nitrogen metabolism in growing rats.

Dietary lysine restriction may differentially affect body growth and lipid and nitrogen metabolism, depending on the degree of lysine restriction. This study was conducted to examine the effect of dietary lysine restriction on growth and lipid and nitrogen metabolism with two different degree of lysine restriction. Isocaloric amino acid-defined diets containing 1.4% lysine (adequate), 0.70% lysine (50% moderate lysine restriction) and 0.35% lysine (75% severe lysine restriction) were fed from the age of 52 to 77 days for 25 days in male Sprague-Dawley rats. The 75% severe lysine restriction increased (p < 0.05) food intake, but retarded (p < 0.05) growth, increased (p < 0.05) liver and muscle lipid contents and abdominal fat accumulation, increased (p < 0.05) blood urea nitrogen levels and mRNA levels of the serine-synthesizing 3-phosphoglycerate dehydrogenase gene, but decreased (p < 0.05) urea cycle arginase gene mRNA levels. In contrast, the 50% lysine restriction did not significantly (p > 0.05) affect body growth and lipid and nitrogen metabolism. Our results demonstrate that severe 75% lysine restriction has detrimental effects on body growth and deregulate lipid and nitrogen metabolism.

Transcriptome changes favoring intramuscular fat deposition in the longissimus muscle following castration of bulls.

Castration increases intramuscular fat (IMF) deposition, improving beef quality in cattle. The present study was performed to determine the global transcriptome changes following castration of bulls and to identify genes associated with IMF deposition in the longissimus dorsi (LM) of Korean cattle. A customized bovine CombiMatrix oligonucleotide microarray was constructed, and transcriptome changes following castration were determined by microarray hybridization. Transcriptome comparison between bulls and steers indicated that 428 of 8,407 genes were differentially expressed in the LM by greater than two fold (P < 0.05). Gene expression profiling indicated alterations in several pathways, including adipogenesis, fatty acid oxidation, tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OP), following castration. Castration upregulated transcription of adipogenic perilipin 2 (PLIN2) and visfatin, lipogenic fatty acid synthase, fatty acid esterification 1-acylglycerol-3-phosphate O-acyltransferase 5, and many fatty acid oxidation-related genes. Many TCA cycle and OP genes were also transcriptionally upregulated. Correlation analysis indicated that the IMF content in the LM was highly correlated with mRNA levels of PLIN2 (r = 0.70, P < 0.001), adenosine triphosphatase (ATPase), H(+)-transporting, lysosomal 42 kDa, V1 subunit C1 (ATP6V1C1: r = 0.66, P < 0.001), and cytochrome c oxidase assembly homolog 11 (COX11: r = 0.72, P < 0.001) genes in a pooled animal group of steers plus bulls, and significant correlations in the steer-alone group were maintained in the 3 genes, PLIN2 (r = 0.47, P < 0.05), ATP6V1C1 (r = 0.50, P < 0.05), and COX11 (r = 0.60, P < 0.01). In conclusion, our study provided evidence that castration shifts transcription of lipid metabolism genes, favoring IMF deposition by increasing adipogenesis, lipogenesis, and triglyceride synthesis. This study also indicated that castration increases transcription of genes involved in fatty acid oxidation and subsequent energy production (TCA and OP genes). Our microarray analysis provided novel information that castration alters the transcriptome associated with lipid/energy metabolism, favoring IMF deposition in the LM.

Wnt/ß-catenin signaling and adipogenic genes are associated with intramuscular fat content in the longissimus dorsi muscle of Korean cattle.

Intramuscular fat (IMF) is an important trait that influences beef quality. In two studies, we examined the possible involvement of the Wnt/ß-catenin signaling pathway in IMF deposition in Korean cattle. In study 1, using a group of bulls and steers, we found that castration, a non-genetic factor, decreased (P < 0.01) the expression of both the WNT10B and CTNNB1 genes, whereas it increased the expression of the Wnt antagonist secreted frizzled-related proteins 4 (SFRP4, P < 0.001) and the adipogenic CCAAT/enhancer binding protein (C/EPB), alpha (CEBPA, P < 0.001) and peroxisome proliferator-activated receptor gamma (PPARG, P < 0.05) genes in longissimus dorsi muscle (LM) tissue. The WNT10B and CTNNB1 mRNA levels showed strong (P < 0.001) negative correlations (r = -0.68 and r = -0.73 respectively) with the IMF content, whereas the SFRP4, CEBPA and PPARG mRNA levels showed strong (P < 0.01) positive correlations (r = 0.70, 0.70 and 0.64 respectively) with the IMF content. Large variation still exists in the IMF content of steers, implying that genetic factors affect IMF deposition. Using a different group of steers, a correlation analysis in study 2 also showed that the expression of the WNT10B and CTNNB1 genes, and SFRP4 and adipogenic genes was negatively and positively associated with the IMF content respectively. Our findings suggest that downregulation of the Wnt/ß-catenin signaling pathway genes, but upregulation of Wnt antagonist SFRP4 and adipogenic gene expression following castration, contributes to increased IMF deposition in the LM. Our results demonstrate that both non-genetic factors (castration) and genetic variation within the steer group affect the gene expression pattern of the Wnt/ß-catenin signaling pathway.

Expression of fat deposition and fat removal genes is associated with intramuscular fat content in longissimus dorsi muscle of Korean cattle steers.

Intramuscular fat (IMF) in cattle is an important component of traits that influence meat quality. We measured carcass characteristics and gene expression in Korean steers to clarify the molecular mechanism(s) underlying IMF deposition in LM tissue by determining the correlation between IMF content and gene expression abundance and by developing models to predict IMF content using gene expression abundance. The deposition of IMF is determined by a balance between fat deposition and fat removal in the LM. We measured mRNA abundance of lipid metabolic genes including lipogenesis [acetyl CoA carboxylase (ACC), fatty acid synthase (FASN)], fatty lipid uptake [lipoprotein lipase (LPL), fatty acid translocase (CD36), fatty acid transport protein 1 (FATP1)], fatty acid esterification [glycerol-3-phosphate acyltransferase 1 (GPAT1), acylglycerol phosphate acyltransferase 1 (AGPAT1), diacylglycerol acyltransferase 1 (DGAT1), DGAT2], lipolysis [adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), monoglyceride lipase (MGL)], and fatty acid oxidation [carnitine palmitoyl transferase 1B, very long-chain acyl-CoA dehydrogenase (VLCAD), medium-chain acyl-CoA dehydrogenase (MCAD)] in the LM. The mRNA abundance of the GPAT1 gene showed the greatest correlation (r = 0.74; P < 0.001) with IMF content among 9 fat deposition genes. The gene expression abundance of other fat deposition genes including ACC, FASN, LPL, CD36, FATP1, AGPAT1, DGAT1, and DGAT2 also exhibited significant positive correlations (P < 0.05) with IMF content in the LM. Conversely, ATGL mRNA abundance showed the greatest negative correlation (r = -0.68; P < 0.001) with IMF content in the LM among 6 fat removal genes. The expression of other fat removal genes including MGL, VLCAD, and MCAD showed significant negative correlations (P < 0.05) with IMF content. Our findings show that the combined effects of increases in lipogenesis, fatty acid uptake, fatty acid esterification, and of decreases in lipolysis and fatty acid oxidation contribute to increasing IMF deposition in Korean steers. The multiple regression analysis revealed that the mRNA abundance of the GPAT1 gene in the LM was the first major variable predicting IMF content (54%) among 15 lipid metabolic genes. The second was mRNA abundance of ATGL (11%). In conclusion, these results suggest that GPAT1 and ATGL genes could be used as genetic markers to predict IMF deposition in the LM.

Chemical structure and physical properties of mung bean starches isolated from 5 domestic cultivars.

Chemical structure and physical properties of starches isolated from 5 domestic mung bean cultivars (Gyungsun, Geumsung, Sunhwa, Eohul, and Jangan) were examined. The granules were jelly bean like in shape and smooth on surface, and the size was within 10 to 30 microm. Mung bean starches displayed a C(A)-type crystalline structure when judged by the X-ray diffraction patterns. Branch chain-length distribution patterns of amylopectin (AP) revealed that peak chain length of APs was at either DP (degree of polymerization) 12 or DP13. Apparent amylose contents of 5 cultivars by iodine affinity test were 31.7% to 33.8%. Mung bean APs showed a unique molecular size distribution that has not been observed from other plant-derived starches. Two distinct peaks of AP fraction were identified on the size-exclusion chromatogram, and the ratios of these 2 peaks were different depending on the mung bean cultivars. Weight-average chain length (CL(avg)) of APs was in the range of 16.9 (Eohul) and 17.5 (Geumsung). The onset temperature (T(o)) and enthalpy change (DeltaH(gel)) of starch gelatinization were 54.6 to 60.2 degrees C and 11.6 to 13.2 J/g. The DeltaH of the retrograded mung bean starches was 5.5 to 6.6 J/g, which indicated 44.5% to 52.7% of recrystallization. The pasting temperature, peak viscosity, and setback were 66.1 to 69.2 degrees C, 510 to 579 Rapid Visco Unit (RVU), and 66 to 90 RVU, respectively.

Effects of glycerol and moisture gradient on thermomechanical properties of white bread.

The thermomechanical properties of breadcrumb were investigated using dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). The main transition (T(1), near 0 degrees C) shifted to lower temperature with added glycerol due to freezing point depression. The low-temperature transition (T(3), approximately -50 degrees C), found only in high-glycerol (8.8%) bread, suggested that of excess or phase-separated glycerol. The high-temperature transition (T(2), 60-85 degrees C) appeared only in aged breadcrumbs; its temperature range was correlated well with the amylopectin melting transition (DSC) but its tan delta amplitude did not correlate well with the amylopectin melting enthalpy (r(2) = 0.72). On the other hand, the change of E' ' (viscous behavior) suggested that T(2) might be related to the change in the amorphous region. Domain-to-domain (amorphous) and crumb-to-crust moisture migrations are two critical phenomenological changes associated with aging and could lead to significant local dehydration of some amorphous regions contributing to mechanical firming during storage.

Synthesis, structure, and electronic properties of monomeric and dimeric trispyrazolylborate platinum(II) hydride complexes.

Tp'PtMe(H)2 (2) [Tp' = hydridotris(3,5-dimethylpyrazolyl)borate] has been prepared from Tp'PtMe(CO) (1) via reaction with water in a basic acetone/water mixture. Protonation of 2 at one of the pyrazole nitrogen atoms induces methane elimination, and the resulting platinum(II) monohydride solvent intermediate (3) can be trapped by added ligand. Two chiral cationic platinum(II) monohydride complexes of the type [kappa(2)-((Hpz)BHpz2)Pt(H)(L)][BAr'4] [L = MeCN (4), CH2=CH2 (5); pz = 3,5-dimethylpyrazolyl, BAr'4 = tetrakis(3,5-trifluoromethylphenyl)borate] have been isolated. If 2 is protonated in the absence of trapping ligand, a deep red hydride-bridged dinuclear complex, [kappa(2)-((Hpz)BHpz2)Pt(mu-H)]2[BAr'4]2 (6), forms. DFT calculations supplement intuitive expectations regarding 3-center-2-electron bridging orbital descriptions for the electronic structure of this complex. X-ray structure determinations for the monomeric acetonitrile adduct 4 and the dicationic dimer 6 are reported.

Laboratory migration experiments with radionuclides and natural colloids in a granite fracture.

Natural colloids in groundwater could facilitate radionuclide transport, provided the colloids are mobile, are present in sufficient concentrations and can adsorb radionuclides. This paper describes the results of a laboratory migration study carried out with combinations of radionuclides and natural colloids within a fracture in a large granite block to experimentally determine the impact of colloids on radionuclide transport. The 85Sr used in this study is an example of a moderately sorbing radionuclide, while the 241Am is typical of a strongly sorbed radionuclide with very low solubility. The natural colloids used in this study were isolated from granite groundwater from Atomic Energy of Canada (AECL) Underground Research Laboratory (URL), and consisted of mostly 1-10 nm organic colloids, along with lesser amounts of 10-450 nm colloids (organics and aluminosilicates). The measured coefficients for radionuclide sorption onto these colloids were between 3 x 10(2) and 1 x 10(3) ml/g for 85Sr, and between 7 x 10(4) and 7 x 10(5) mg/l for 241Am. The 85Sr sorption on the natural colloids appeared to be reversible. Migration experiments in the granite block were carried out by establishing a flow field between two boreholes (out of a total of nine) intersecting a main horizontal fracture. These experiments showed that dissolved 85Sr behaved as a moderately sorbing tracer, while dissolved 241Am was completely adsorbed by the fracture surfaces and showed no evidence of transport. However, when natural colloids were injected together with dissolved 241Am, a small amount of 241Am transport was observed, demonstrating the ability of natural colloids to facilitate the transport of radionuclides with low solubility. Natural colloids had only a minor effect on the transport of 85Sr. In a separate experiment to test the effect of higher colloid concentrations on 85Sr migration, synthetic colloids were produced from Avonlea bentonite. The introduction of a relatively high concentration of bentonite colloids actually reduced 85Sr transport because, compared to natural colloids, the bentonite colloids were less mobile and they sorbed 85Sr more strongly.

Molecular cloning and cultivar specific expression of MAP kinases from Capsicum annuum.

Two MAP kinases, MK1 and MK2, were cloned from Capsicum annuum (pepper) cv. Subicho using a parsley MAP kinase gene as a heterologous probe. MK1 and MK2 encode stress-inducible protein kinases that can contribute to the response to wounding, UV-C, and cold. MK1 has a 92% amino acid identity with WIPK of tobacco. It was transcriptionally induced in response to wounding. In contrast, no detectable MK1 transcript was found in unwounded leaves of pepper. MK2 has a high level of amino acid homology to MAP kinases, such as NTF4 and SIPK and was constitutively expressed in all tissues. Both MK transcripts were downregulated by UV-C treatment. Each MK protein activation was independently wound-inducible in a cultivar dependent manner. MK1 is phosphorylated in cv. Pungchon but not cv. Subicho; whereas, the MK2 protein activation by wounding is restricted to cv. Subicho. In addition, de novo synthesis of the MK1 protein and tyrosine phosphorylation was rapidly and transiently induced in cv. Pungchon by wounding. In contrast, it is highly unlikely that the MK1 protein is produced in cv. Subicho, even though there is an abundant expression of MK1 mRNA after wounding in this cultivar. In Escherichia coli, which overexpresses MK1, autophosphorylation is observed at conserved threonine and tyrosine phosphorylation sites.

The expression of Bok is regulated by serum in HC11 mammary epithelial cells.

Epithelial cells within the mammary gland undergo apoptosis during weaning. To determine the expression of Bok mRNA (a member of the pro-apoptotic Bcl-2 family) in the mammary gland and its regulation, we examined the expression of the Bok transcript in the mouse mammary gland and HC11 mammary epithelial cells in culture through RT-PCR. The Bok mRNA expression was found in the mammary gland. The expression of the Bok mRNA level was induced through serum starvation and overexpression of Bok induced apoptosis in HC11 cells in culture. These results indicate that the expression of Bok mRNA in the mammary gland is regulated through serum starvation. It also may be related to the mammary involution.