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Branched-chain volatile fatty acids (BCVFA) supplements could promote lactation performance and milk quality by improving ruminal fermentation and milk fatty acid synthesis. This study was conducted to evaluate the effects of BCVFA supplementation on milk performance, ruminal fermentation, nutrient digestibility and mRNA expression of genes related to fatty acid synthesis in mammary gland of dairy cows. A total of 36 multiparous Chinese Holstein cows averaging 606±4.7 kg of BW, 65±5.2 day in milk (DIM) with daily milk production of 30.6±0.72 kg were assigned to one of four groups blocked by lactation number, milk yield and DIM. The treatments were control, low-BCVFA (LBCVFA), medium-BCVFA (MBCVFA) and high-BCVFA (HBCVFA) with 0, 30, 60 and 90 g BCVFA per cow per day, respectively. Experimental periods were 105 days with 15 days of adaptation and 90 days of data collection. Dry matter (DM) intake tended to increase, but BW changes were similar among treatments. Yields of actual milk, 4% fat corrected milk, milk fat and true protein linearly increased, but feed conversion ratio (FCR) linearly decreased with increasing BCVFA supplementation. Milk fat content linearly increased, but true protein content tended to increase. Contents of C4:0, C6:0, C8:0, C10:0, C12:0, C14:0 and C15:0 fatty acids in milk fat linearly increased, whereas other fatty acids were not affected with increasing BCVFA supplementation. Ruminal pH, ammonia N concentration and propionate molar proportion linearly decreased, but total VFA production and molar proportions of acetate and butyrate linearly increased with increasing BCVFA supplementation. Consequently, acetate to propionate ratios linearly increased. Digestibilities of DM, organic matter, CP, NDF and ADF also linearly increased. In addition, mRNA expressions of peroxisome proliferator-activated receptor γ , sterol regulatory element-binding factor 1 and fatty acid-binding protein 3 linearly increased, mRNA expressions of acetyl-coenzyme A carboxylase- α , fatty acid synthase and stearoyl-CoA desaturase quadratically increased. However, lipoprotein lipase mRNA expression was not affected by treatments. The results indicated that lactation performance and milk fat synthesis increased with BCVFA supplementation by improving ruminal fermentation, nutrient digestibility and mRNA expressions of genes related to milk fat synthesis. [ABSTRACT FROM AUTHOR]

Abstract: A critical period in respiratory network development occurs in the rat around postnatal days (P) 12–13, when abrupt neurochemical, metabolic, and physiological changes were evident. As serotonin and its receptors are involved in respiratory modulation, and serotonergic abnormality is implicated in sudden infant death syndrome, we hypothesized that 5-HT receptors are significantly downregulated during the critical period. This was documented recently for 5-HT2AR in several respiratory nuclei. The present study represents a comprehensive analysis of postnatal development of 5-HT1AR and 5-HT1BR in 10 brain stem nuclei and 5-HT2AR in six nuclei not previously examined. Optical densitometric analysis of immunohistochemically-reacted neurons from P2 to P21 indicated four developmental patterns of expression: (1) Pattern I: a high level of expression at P2-P11, an abrupt and significant reduction at P12, followed by a plateau until P21 (5-HT1AR and 5-HT1BR in raphé magnus [RM], raphé obscurus [ROb], raphé pallidus [RP], pre-Bötzinger complex [PBC], nucleus ambiguus [Amb], and hypoglossal nucleus [XII; 5-HT1AR only]). (2) Pattern II: a high level at P2-P9, a gradual decline from P9 to P12, followed by a plateau until P21 (5-HT1AR and 5-HT1BR in the retrotrapezoid nucleus (RTN)/parafacial respiratory group (pFRG)). (3) Pattern III: a high level at P2-P11, followed by a gradual decline until P21 (5-HT1AR in the ventrolateral subnucleus of solitary tract nucleus [NTSVL] and the non-respiratory cuneate nucleus [CN]). (4) Pattern IV: a relatively constant level maintained from P2 to P21 (5-HT1AR in the commissural subnucleus of solitary tract nucleus (NTSCOM); 5-HT1BR in XII, NTSVL, NTSCOM, and CN; and 5-HT2AR in RM, ROb, RP, RTN/pFRG, NTSVL, and NTSCOM). Thus, a significant reduction in the expression of 5-HT1AR, 5-HT1BR, and 5-HT2AR in multiple respiratory-related nuclei at P12 is consistent with reduced serotonergic transmission during the critical period, thereby rendering the animals less able to respond adequately to ventilatory distress. [Copyright &y& Elsevier]

Abstract: Background: Livers exposed to warm ischemia (WI) are increasingly used for transplantation. The molecular mechanisms activated by WI alone (prior to procurement and transplantation) are not understood. To elucidate the pathways involved, we used microarrays to investigate the gene expression in porcine livers exposed to WI. Methods: Porcine livers (n = 6 group) were randomly subjected to WI periods of 15, 30 or 45 minutes. mRNA was extracted and gene expression determined by microarray analysis. Using bioinformatics software, we identified differentially expressed genes and related molecular pathways. We used the corresponding human annotation of the porcine microarray for the functional analysis. Results: Between 0 and 15 minutes of WI, 3530 genes were altered with a 2-log-fold change of <−0.58 or >+0.58 and P < .05. Between 0 and 30 minutes of WI, 4141 genes were differentially expressed; and between 0 and 45 minutes of WI, 2814 genes. At each time point, ∼50% of genes were up-regulated, whereas 50% were down-regulated. After pathway mapping, we found that the same pathways were induced for observed clustering of in the three WI periods: cell death, proliferation, inflammation, and metabolism pathways. Among the top genes that were up-regulated after 15 minutes of WI, the majority started to return to but did not reach baseline expression with increasing WI. A similar pattern was observed for the top suppressed genes. Conclusions: WI causes rapid changes in gene expression that affect several molecular pathways. This phenomenon seems to plateau at 15 to 30 minutes of WI. These new insights in the timing and the nature of molecular pathways induced by WI alone may help to design specific interventions to alter these changes and improve the outcome of livers from cardiac death donors. [Copyright &y& Elsevier]

Abstract: Proteolytic activity is important in the lifecycles of parasites and their interactions with hosts. Cysteine proteases have been best studied in Giardia, but other protease classes have been implicated in growth and/or differentiation. In this study, we employed bioinformatics to reveal the complete set of putative proteases in the Giardia genome. We identified 73 peptidase homologs distributed over 5 catalytic classes in the genome. Serial analysis of gene expression of the G. lamblia lifecycle found thirteen protease genes with significant transcriptional variation over the lifecycle, with only one serine protease transcript upregulated late in encystation. The translated gene sequence of this encystation-specific transcript was most similar to eukaryotic subtilisin-like proprotein convertases (SPC), although the typical catalytic triad was not identified. Epitope-tagged gSPC protein expressed in Giardia under its own promoter was upregulated during encystation with highest expression in cysts and it localized to encystation-specific secretory vesicles (ESV). Total gSPC from encysting cells produced proteolysis in gelatin gels that co-migrated with the epitope-tagged protease in immunoblots. Immuno-purified gSPC also had gelatinase activity. To test whether endogenous gSPC activity is involved in differentiation, trophozoites and cysts were exposed to the specific serine proteinase inhibitor 4-(2-aminoethyl)-benzenesulfonyl fluoride hydrochloride (AEBSF). After 21h encystation, a significant decrease in ESV was observed with 1mM AEBSF and by 42h the number of cysts was significantly reduced, but trophozoite growth was not inhibited. Concurrently, levels of cyst wall proteins 1 and 2, and AU1-tagged gSPC protein itself were decreased. Excystation of G. muris cysts was also significantly reduced in the presence of AEBSF. These results support the idea that serine protease activity is essential for Giardia encystation and excystation. [Copyright &y& Elsevier]

Abstract: B-cell activating factor belonging to the tumor necrosis factor superfamily (BAFF) is a critical regulator of B-cell maturation and survival. We investigated the expression of BAFF in peripheral blood sample from kidney transplant recipients. Results of flow cytometry showed that at 5 years or more posttransplantation, cell-surface BAFF was significantly expressed on peripheral CD3+ T lymphocytes kidney transplant recipients in compared with other groups (P < .05). BAFF expression was noted on CD4+ and CD8+ T cells. The BAFF messenger RNA level in peripheral mononuclear cells was consistent with the protein level. However, the serum soluble BAFF level varied among individuals in each group. Stratified by renal function, the cell-surface BAFF level was significantly higher in recipients with abnormal renal function compared with those with normal renal function (P < .05). Enzyme-linked immunosorbent assay results showed that expression level of cell-surface BAFF significantly correlated with panel reactive antibody. These results indicate that BAFF may be involved in the development of graft loss. [Copyright &y& Elsevier]

Abstract: Cathepsin K (CatK) is a cysteine protease expressed predominantly in osteoclasts, that plays a prominent role in degrading Type I collagen. Growing CatK null mice have osteopetrosis associated with a reduced ability to degrade bone matrix. Bone strength and histomorphometric endpoints in young adult CatK null mice aged more than 10 weeks have not been studied. The purpose of this paper is to describe bone mass, strength, resorption, and formation in young adult CatK null mice. In male and female wild-type (WT), heterozygous, and homozygous CatK null mice (total N =50) aged 19 weeks, in-life double fluorochrome labeling was performed. Right femurs and lumbar vertebral bodies 1–3 (LV) were evaluated by dual-energy X-ray absorptiometry (DXA) for bone mineral content (BMC) and bone mineral density (BMD). The trabecular region of the femur and the cortical region of the tibia were evaluated by histomorphometry. The left femur and sixth lumbar vertebral body were tested biomechanically. CatK (−/−) mice show higher BMD at the central and distal femur. Central femur ultimate load was positively influenced by genotype, and was positively correlated with both cortical area and BMC. Lumbar vertebral body ultimate load was also positively correlated to BMC. Genotype did not influence the relationship of ultimate load to BMC in either the central femur or vertebral body. CatK (−/−) mice had less lamellar cortical bone than WT mice. Higher bone volume, trabecular thickness, and trabecular number were observed at the distal femur in CatK (−/−) mice. Smaller marrow cavities were also present at the central femur of CatK (−/−) mice. CatK (−/−) mice exhibited greater trabecular mineralizing surface, associated with normal volume-based formation of trabecular bone. Adult CatK (−/−) mice have higher bone mass in both cortical and cancellous regions than WT mice. Though no direct measures of bone resorption rate were made, the higher cortical bone quantity is associated with a smaller marrow cavity and increased retention of non-lamellar bone, signs of decreased endocortical resorption. The relationship of bone strength to BMC does not differ with genotype, indicating the presence of bone tissue of normal quality in the absence of CatK. [Copyright &y& Elsevier]

• Both sodium selenite (SS) and coated SS (CSS) addition increased dry matter intake. • Only CSS supplement increased average daily gain and reduced feed conversion ratio. • Ruminal fermentation and nutrient digestibility were promoted by SS and CSS supplements. • The CSS supplement increased serum total protein, albumin, triglyceride and total antioxigenic capacity. • The CSS addition was more efficient in stimulating hepatic gene expression related to lipid metabolism than SS addition. This study evaluated the effects of sodium selenite (SS) and coated SS (CSS) addition on performance, ruminal fermentation, nutrient digestibility and hepatic gene expression related to lipid metabolism in dairy bulls. Thirty-six Holstein bulls were randomly divided into three groups: without Se addition, addition of 0.3 mg/kg dry matter (DM) of Se from SS and addition of 0.3 mg/kg DM of Se from CSS, respectively. Dietary Se addition increased DM intake. Higher average daily gain and lower feed conversion ratio was observed for CSS addition. Ruminal pH and acetate to propionate ratio decreased, total volatile fatty acids concentration increased but ammonia-N concentration was unchanged with dietary Se addition. Apparent total-tract digestibility of DM, organic matter and crude protein was highest for CSS addition, followed by SS addition and then control. Bulls receiving Se addition had higher digestibility of ether extract, neutral detergent fibre and acid detergent fibre. Serum glucose and glutathione peroxidase and hepatic expression of peroxisome proliferator-activated receptor-α, sterol regulatory element-binding protein-1, carnitine palmitoyl transferase-1 and acetyl-CoA carboxylase-α was highest for CSS addition, followed by SS addition and then control. Bulls receiving CSS addition had higher serum total protein, albumin, triglyceride and total antioxigenic capacity. Addition of Se increased serum cholesterol, insulin and Se. Hepatic expression of stearoyl-CoA desaturase and 3‑hydroxy‑3-methylglutaryl-CoA reductase and Se content increased but content of total lipid and triglyceride was unchanged with Se addition. The data indicated that addition of Se increased performance and hepatic expression of gene related to lipid metabolism in bulls. [ABSTRACT FROM AUTHOR]