Effects of ACTH administration on bovine polymorphonuclear leukocyte function and lymphocyte blastogenesis

Yearling steers were treated with ACTH to determine the effect of increased plasma cortisol concentration on bovine lymphocyte and polymorphonuclear leukocyte (PMN) function. The administration of ACTH caused a significant (P less than 0.01) increase in serum cortisol concentration and depression of lymphocyte blastogenesis in response to phytohemagglutinin and concanavalin A. The response to pokeweed mitogen was also depressed, but not significantly. Random migration by PMN was significantly enhanced by ACTH treatment, but there was no effect on ingestion of Staphylococcus aureus, nitroblue tetrazolium reduction, or antibody-dependent cell-mediated cytotoxicity by PMN. The iodination reaction, which evaluates the activity of the myeloperoxidase-hydrogen peroxide-halide antibacterial system of the PMN, was significantly impaired after ACTH treatment. These data indicate that specific parameters of lymphocyte and neutrophil function were impaired directly or indirectly by elevated in vivo concentrations of plasma cortisol.     

The right and the good: distributive justice and neural encoding of equity and efficiency

Distributive justice concerns how individuals and societies distribute benefits and burdens in a just or moral manner. We combined distribution choices with functional magnetic resonance imaging to investigate the central problem of distributive justice: the trade-off between equity and efficiency. We found that the putamen responds to efficiency, whereas the insula encodes inequity, and the caudate/septal subgenual region encodes a unified measure of efficiency and inequity (utility). Notably, individual differences in inequity aversion correlate with activity in inequity and utility regions. Against utilitarianism, our results support the deontological intuition that a sense of fairness is fundamental to distributive justice but, as suggested by moral sentimentalists, is rooted in emotional processing. More generally, emotional responses related to norm violations may underlie individual differences in equity considerations and adherence to ethical rules.     

An insulin-stimulated protein kinase similar to yeast kinases involved in cell cycle control

A protein kinase characterized by its ability to phosphorylate microtubule-associated protein-2 (MAP2), is thought to be an early intermediate in an insulin-stimulated phosphorylation cascade and in a variety of other mammalian cell responses to extracellular signals. A complementary DNA that encodes this protein serine-threonine kinase has been cloned, and the protein designated extracellular signal-regulated kinase 1 (ERK1). ERK1 has striking similarity to two protein kinases, KSS1 and FUS3, from yeast. The yeast kinases function in an antagonistic manner to regulate the cell cycle in response to mating factors. Thus, ERK1 and the two yeast kinases constitute a family of evolutionarily conserved enzymes involved in regulating the response of eukaryotic cells to extracellular signals.     

Selection of amino acid sequences in the beta chain of the T cell antigen receptor

The induction of an immune response in mammals is initiated by specifically reactive T lymphocytes. The specificity of the reaction is mediated by a complex receptor, part of which is highly variable in sequence and analogous to immunoglobulin heavy- and light-chain variable domains. The functional specificity of the T cell antigen receptor is, however, markedly different from immunoglobulins in that it mediates cell-cell interactions via the simultaneous recognition of foreign antigens and major histocompatibility complex-encoded molecules expressed on the surface of various lymphoid and nonlymphoid cells. The relation between the structure of the receptor and its functional specificity was investigated by analyzing the primary sequences of the receptors expressed by a series of T lymphocyte clones specific for a model antigen, pigeon cytochrome c. Within this set of T lymphocyte clones there was a striking selection for amino acid sequences in the receptor beta-chain in the region analogous to the third complementarity-determining region of immunoglobulins. Thus, despite the functional differences between T cell antigen receptors and immunoglobulin molecules, analogous regions appear to be important in determining ligand specificity.     

Studies on Ancient Rice—Where Botanists, Agronomists, Archeologists, Linguists, and Ethnologists Meet

Taiwan’s aboriginal peoples are thought to be related to ancestral Austronesian-speaking peoples. Currently, Taiwan has 14 officially acknowledged aboriginal tribes. The major crops currently farmed in aboriginal areas are rice (Oryza sativa) and foxtail millet (Setaria italica). Archeologists recently excavated the remains of several early cultures in Taiwan. The most plentiful plant remains were carbonated rice and foxtail millet grains. The earliest ¹⁴C date of these excavation sites is ～5,000 bp. These settlements may be those of the earliest ancestral Austronesian speakers in Taiwan. Rice domestication is a complex story. In this study, we identified the functional nucleotide polymorphisms of 16 domestication-related genes using 60 landraces collected from aboriginal Taiwanese villages about 100 years ago. We also screened the phenotypes of these landraces. By integrating pheno- and genotypic data, together with data from archeologists and linguists, we may be able to better understand the history of rice cultivation in Taiwan and nearby areas.     

Functional and phylogenetic analyses of a melanocortin-4 receptor mutation in domestic pigs

The melanocortin-4 receptor (MC4R), a G protein-coupled seven-transmembrane receptor, which is expressed in the brain, plays an important role in the control of mammalian energy homeostasis. A missense mutation (Asp298Asn) was identified in the porcine MC4R gene, which is associated with growth and food intake traits. The Asn298 mutation occurs within a highly conserved motif, NPLIY, of all members of G protein-coupled receptors; whereas, Asp298 is conserved in all five melanocortin receptor subtypes. Functional analysis of the porcine MC4R variant was performed with an in vitro gene expression system in 293 cells. Ligand binding (NDP-alphaMSH) did not differ between Asp298 and Asn298 MC4R proteins. However, the Asn298 MC4R variant was unable to stimulate cAMP production in response to NDP-alphaMSH stimulation; whereas, the Asp298 variant could stimulate cAMP accumulation. These results demonstrate that the Asp298 is required for normal MC4R signaling to the adenylyl cyclase. Sequencing of the MC4R gene of seven diverse genera within the Suiformes that include Hippopotamidae (hippos), Tayassuidae (peccaries) and Suidae (pigs), revealed 62 nucleotide variations in MC4R. Phylogenetic relationships of MC4R variations are consistent with those previously described from morphological and physiological data among the subfamilies of the Suiformes. These findings revealed that a single missense mutation (Asp298Asn) of aspartic acid (Asp) to asparagine (Asn) in MC4R gene decreased cAMP content and MC4R signaling, but with no difference in the ligand binding was associated with growth and feed intake traits in domestic pigs.     

Peptides derived from atlantic salmon skin gelatin as dipeptidyl-peptidase IV inhibitors

The dipeptidyl-peptidase IV (DPP-IV)-inhibitory activity of peptides derived from Atlantic salmon skin gelatin hydrolyzed by alcalase (ALA), bromelain (BRO), and Flavourzyme (FLA) was determined. The FLA hydrolysate with the enzyme/substrate ratio of 6% showed the greatest DPP-IV-inhibitory activity. The hydrolysate was fractionated by ultrafiltration with 1 and 2.5 kDa cutoff membranes, and the <1 kDa fraction had the highest DPP-IV-inhibitory activity with an IC(50) value of 1.35 mg/mL. The F-1 fraction further isolated by HPLC showed the IC(50) value against DPP-IV of 57.3 μg/mL, and the peptide sequences were identified as Gly-Pro-Ala-Glu (372.4 Da) and Gly-Pro-Gly-Ala (300.4 Da). The synthetic peptides showed dose-dependent inhibition effects on DPP-IV with IC(50) values of 49.6 and 41.9 μM, respectively. The results suggest that the peptides derived from Atlantic salmon skin gelatin would be beneficial ingredients for functional foods or pharmaceuticals against type 2 diabetes.     

Changes in gelatinization and rheological characteristics of japonica rice starch induced by pressure/heat combinations

Rice starch suspensions of 10% dry matter (DM) were treated by heat (0.1 MPa at 20–85 °C) or pressure/heat combinations (100–600 MPa at 20, 40 and 50 °C) for 15 min to investigate their gelatinization and rheological characteristics. The maximum swelling index of about 12 g water per gram of DM was obtained by thermal treatment at 85 °C, meanwhile, that of 7.0 g was observed by 600-MPa pressurization at 50 °C. The higher temperatures or pressures resulted in the higher degrees of gelatinization. Furthermore, treatments of 0.1 MPa at 85 °C, 500 MPa at 50 °C and 600 MPa at various temperatures caused complete gelatinization of rice starch. The consistency index (K) and storage modulus (G′) dramatically increased from 70 °C or 400 MPa. The G′ values were higher in pressure-treated samples than those in thermal-treated samples. Therefore, an application of pressure/heat combinations as a processing method to improve the quality of rice starch products would be possible.     

Detection of race 1 strains of <Emphasis Type="Italic">Ralstonia solanacearum</Emphasis> in field samples in Taiwan using a BIO-PCR method

Bacterial wilt caused by race 1 strains of Ralstonia solanacearum is endemic on tomato produced in diverse agro-ecosystems in Taiwan. Using a new BIO-PCR protocol developed in this study, R. solanacearum was detected in soil, weed, and water samples collected from eight fields with different disease histories and cropping systems located in major tomato production areas. The sensitivity of the BIO-PCR was 1.9 CFU ml⁻¹ and 17 CFU g⁻¹ of soil for pure suspension and infested soil, respectively. The positive detection frequency of the BIO-PCR method was 66.6, 39.6, 23.1, and 31.8% for all tested samples of soil, weed rhizosphere soil, weed root, and water, respectively, and was higher than plating on MSM-1 medium. Detection of R. solanacearum from field soil indicated that spatial distribution of the pathogen in the field was not even regardless of the presence or absence of the disease and the different agro-ecosystems where the sampled fields were located, and the degree of unevenness was higher when tomato was absent from the field. Weed rhizosphere soils could be good sampling targets to monitor the pathogen in the field, because a higher positive detection proportion and population of R. solanacearum were found in the rhizosphere rather than the root of the collected weed samples. Symptomless weeds and contaminated irrigation, standing, or drainage waters were found to be important for the over-season survival and dissemination of R. solanacearum.