Crossbreeding applied to systems of beef cattle production to improve performance traits and carcass quality.

Crossbreeding represents an important technique to improve growth, beef quality and adaptability in beef production systems in tropical countries. The aim of this study was to evaluate sire and dam breed effects on performance and carcass traits of crossbred cattle produced in a tropical environment. Heifers and steers were evaluated during the pre-weaning, the post-weaning (n = 173) and the finishing phase (n = 123). Animals were produced by mating Nellore (N_N), Angus × Nellore (A_N) and Caracu × Nellore (C_N) dams with Braford, Charbray and Caracu sires. After weaning, animals were raised grazing on Marandu grass for 12 months; thereafter they were housed in individual pens and finished in a feedlot, receiving a total mixed ration. Ultrasound carcass evaluations were performed to determine ribeye area (R_A), backfat thickness (B_T) and rump fat thickness (R_T). A_N progeny were heavier at birth than N_N (P < 0.05), and Braford progeny had greater birth BW than Caracu (P < 0.05). Greater weaning BW was observed in the A_N and C_N offspring compared to N_N (P < 0.01). Greater average daily gain during the post-weaning period was verified in the N_N progeny compared to C_N (P < 0.05). No dam or sire breed effects were observed for BW at the end of the post-weaning period (P > 0.05). Progeny of N_N cows had greater B_T (P < 0.05) and R_T (P < 0.01) at the end of the post-weaning period in relation to C_N. Greater R_A was observed in the Caracu progeny than in the Braford (P < 0.05), which showed greater R_T than the Charbray progeny at the end of the post-weaning period (P < 0.05). No dam or sire breed effects were verified for final BW at the feedlot or for feed efficiency traits (P > 0.05). A_N progeny were superior in final B_T compared to C_N (P < 0.01), and Braford progeny had greater R_T at the end of finishing than Charbray (P = 0.05). The use of crossbred dams allows an increase in productivity until weaning, but this is not maintained in the post-weaning and finishing periods. The use of Braford sires produces similar growth performance in the different stages of the production system to those seen with Charbray and Caracu sires but generates animals with higher fat thickness at the end of finishing, which may improve carcass quality and commercial value.

Reversible superconductor-insulator transition in LiTi2O4 induced by Li-ion electrochemical reaction.

Transition metal oxides display various electronic and magnetic phases such as high-temperature superconductivity. Controlling such exotic properties by applying an external field is one of the biggest continuous challenges in condensed matter physics. Here, we demonstrate clear superconductor-insulator transition of LiTi2O4 films induced by Li-ion electrochemical reaction. A compact electrochemical cell of pseudo-Li-ion battery structure is formed with a superconducting LiTi2O4 film as an anode. Li content in the film is controlled by applying a constant redox voltage. An insulating state is achieved by Li-ion intercalation to the superconducting film by applying reduction potential. In contrast, the superconducting state is reproduced by applying oxidation potential to the Li-ion intercalated film. Moreover, superconducting transition temperature is also recovered after a number of cycles of Li-ion electrochemical reactions. This complete reversible transition originates in difference in potentials required for deintercalation of initially contained and electrochemically intercalated Li(+) ions.

Isolation and characterization of a novel short peptide associated with Crohn's disease.

Phage display technology has been utilized to select target molecules against circulating antibodies. The aims of this study were to isolate a peptide that binds with serum from Crohn's disease (CD) patients and to examine its diagnostic and pathogenic significance. A phage display library was constructed using cDNA from Caco-2 cells. Affinity selection using this cDNA library and serum samples from patients with CD was then performed. Phage clones that specifically reacted with the CD sera were then selected using a phage enzyme-linked immunosorbent assay (ELISA). After the DNA sequences of the selected phages were determined and converted to amino acid sequences, the synthesized peptides were examined using an ELISA. The effect of the synthesized peptides on cytokine release from cultured blood mononuclear cells was investigated. An ELISA analysis for TCP-353 demonstrated that while 61·7% of the samples from CD patients were seroreactive, seroreactivity was less common among patients with ulcerative colitis (7·3%), acute colitis (0%) or colon cancer (11·4%) and among normal subjects (2·8%). The induction of interleukin (IL)-1ß, IL-6 and tumour necrosis factor (TNF)-α release, but not IL-10 release, in response to TCP-353 peptide was enhanced in CD mononuclear cells only. We isolated a novel peptide that specifically binds to CD sera and stimulates the proinflammatory responses of CD mononuclear cells. TCP-353 may have diagnostic, pathogenic and therapeutic significance with regard to the treatment of CD.

Transient expression of iron transport proteins in the capillary of the developing rat brain.

Iron is essential for normal brain function and its uptake in the developing rat brain peaks during the first two weeks after birth, prior to the formation of the blood­brain barrier (BBB). The first step of iron transport from the blood to the brain is transferrin receptor (TfR)-mediated endocytosis in the capillary endothelial cells. However, the subsequent step from the endothelium into interstitium has not been fully described. The goal of this study was to examine the expression of iron transport proteins by immunodetection and RT­PCR in the developing rat brain. Tf and TfR are transiently expressed in perivascular NG2+ cells of the capillary wall during the early postnatal weeks in the rat brain. However, MTP-1 and hephaestin were expressed in endothelial cells, but not in the NG2+ perivascular cells. Immunoblot analysis for these iron transfer proteins in the developing brain generally confirmed the immunochemical findings. Furthermore, the expression of Tf and TfR in the blood vessels precedes its expression in oligodendrocytes, the main iron-storing cells in the vertebrate brain. RT­PCR analysis for the primary culture of endothelial cells and pericytes revealed that Tf and TfR were highly expressed in the pericytes while MTP-1 and hephaestin were expressed in the endothelial cells. The specific expression of Tf and TfR in brain perivascular cells and MTP-1 and hephaestin in endothelial cells suggest the possibility that trafficking of elemental iron through perivascular cells may be instrumental in the distribution of iron in the developing central nervous system.

Enhanced dopamine function in DISC1-L100P mutant mice: implications for schizophrenia.

Significant advances have been made in understanding the role of disrupted-in-schizophrenia-1 (DISC1) in the brain and accumulating findings suggest the possible implication of DISC1 in the regulation of dopamine (DA) function. A mutation in the second exon of DISC1 at L100P leads to the development of schizophrenia-related behavior in mutant mice (DISC1-L100P). We investigated here the role of DA in the expression of schizophrenia-related endophenotypes in the DISC1-L100P genetic mouse model. The mutated DISC1 resulted in facilitation of the psychostimulant effect of amphetamine in DISC1-L100P mutant mice assessed in the open field and prepulse inhibition (PPI) tests. Biochemical studies detected a 2.1-fold increase in the proportion of striatal D receptors without significant changes in DA release in vivo in the striatum of DISC1-L100P mutants in response to the low dose of amphetamine. The D(2) receptor antagonist haloperidol reversed the hyperactivity, PPI and latent inhibition (LI) deficits and blocked the psychostimulant effect of amphetamine in DISC1-L100P mutants. Taken together, our findings show the role of DISC1 in D(2) -related pathophysiological mechanism of schizophrenia, linking DISC1 with well-established DA hypothesis of schizophrenia.

Silibinin attenuates amyloid beta(25-35) peptide-induced memory impairments: implication of inducible nitric-oxide synthase and tumor necrosis factor-alpha in mice.

In Alzheimer's disease (AD), the deposition of amyloid peptides is invariably associated with oxidative stress and inflammatory responses. Silibinin (silybin), a flavonoid derived from the herb milk thistle, has potent anti-inflammatory and antioxidant activities. However, it remains unclear whether silibinin improves amyloid beta (Abeta) peptide-induced neurotoxicity. In this study, we examined the effect of silibinin on the fear-conditioning memory deficits, inflammatory response, and oxidative stress induced by the intracerebroventricular injection of Abeta peptide(25-35) (Abeta(25-35)) in mice. Mice were treated with silibinin (2, 20, and 200 mg/kg p.o., once a day for 8 days) from the day of the Abeta(25-35) injection (day 0). Memory function was evaluated in cued and contextual fear-conditioning tests (day 6). Nitrotyrosine levels in the hippocampus and amygdala were examined (day 8). The mRNA expression of inducible nitric-oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-alpha) in the hippocampus and amygdala was measured 2 h after the Abeta(25-35) injection. We found that silibinin significantly attenuated memory deficits caused by Abeta(25-35) in the cued and contextual fear-conditioning test. Silibinin significantly inhibited the increase in nitrotyrosine levels in the hippocampus and amygdala induced by Abeta(25-35). Nitrotyrosine levels in these regions were negatively correlated with memory performance. Moreover, real-time RT-PCR revealed that silibinin inhibited the overexpression of iNOS and TNF-alpha mRNA in the hippocampus and amygdala induced by Abeta(25-35). These findings suggest that silibinin (i) attenuates memory impairment through amelioration of oxidative stress and inflammatory response induced by Abeta(25-35) and (ii) may be a potential candidate for an AD medication.

Identification of Piccolo as a regulator of behavioral plasticity and dopamine transporter internalization.

Dopamine transporter (DAT) internalization is a mechanism underlying the decreased dopamine reuptake caused by addictive drugs like methamphetamine (METH). We found that Piccolo, a presynaptic scaffolding protein, was overexpressed in the nucleus accumbens (NAc) of the mice repeatedly administrated with METH. Piccolo downexpression by antisense technique augmented METH-induced behavioral sensitization, conditioned reward and synaptic dopamine accumulation in NAc. Expression of Piccolo C2A domain attenuated METH-induced inhibition of dopamine uptake in PC12 cells expressing human DAT. Consistent with this, it slowed down the accelerated DAT internalization induced by METH, thus maintaining the presentation of plasmalemmal DAT. In immunostaining and structural modeling Piccolo C2A domain displays an unusual feature of sequestering membrane phosphatidylinositol 4,5-bisphosphate, which may underlie its role in modulating DAT internalization. Together, our results indicate that Piccolo upregulation induced by METH represents a homeostatic response in the NAc to excessive dopaminergic transmission. Piccolo C2A domain may act as a cytoskeletal regulator for plasmalemmal DAT internalization, which may underlie its contributions in behavioral plasticity.

Studies on the chemical constituents of Psoralea corylifolia L.

A new isoflavone, corylinin (1), along with six known compounds, isopsoralen (2), psoralen (3), sophoracoumestan A (4), neobavaisoflavone (5), daidzin (6) and uracil (7), have been isolated from the dried fruits of Psoralea corylifolia L. The structure of 1 was established as 7,4'-dihydroxy-3'-[(E)-3,7-dimethyl-2,6-octadienyl]isoflavone on the basis of the spectroscopic methods. Structures of the known compounds were identified by comparison of the literature.

Precipitation of octacalcium phosphates on artificial enamel in artificial saliva.

The natural saliva samples were collected from 30 Japanese men and women aged between 20 and 30, and the inorganic components in the saliva were analyzed chemically. Artificial saliva (AS) was prepared based on the chemical analysis using chemical reagents. The calcium/phosphate molar ratio of the AS was 0.28 with pH=7.0. Artificial enamel (AE) was prepared by sintering hydroxyapatite powder at 1,200 degrees C. The AE was placed in the AS at 37 degrees C. XRD, SEM and EDX investigated precipitation on the AE. The precipitation was always identified as being OCP. As decrease in the pH of the surface of the AE and increase in the concentration of phosphate ions were observed by chemical analysis, it was concluded that the OCP occurs by the pH decrease and phosphate ion concentration increase on the surface of AE.

Tumor suppressive efficacy through augmentation of tumor-infiltrating immune cells by intratumoral injection of chemokine-expressing adenoviral vector.

Our goal in the present study was to evaluate antitumor effects and frequency of tumor-infiltrating immune cells upon intratumoral injection of RGD fiber-mutant adenoviral vector (AdRGD) encoding the chemokines CCL17, CCL19, CCL20, CCL21, CCL22, CCL27, XCL1, and CX3CL1. Among eight kinds of chemokine-expressing AdRGDs, AdRGD-CCL19 injection most efficiently induced infiltration of T cells into established B16BL6 tumor parenchyma, whereas most of these T cells were perforin-negative in immunohistochemical analysis. Additionally, the growth of AdRGD-CCL19-injected tumors decreased only slightly as well as that of other tumors treated with each chemokine-expressing AdRGD, which indicated that accumulation of naive T cells in tumor tissue does not effectively damage the tumor cells. Tumor-bearing mice, in which B16BL6-specific T cells were elicited by dendritic cell-based immunization, demonstrated that intratumoral injection of AdRGD-CCL17, -CCL22, or -CCL27 could considerably suppress tumor growth and attract activated T cells. On the other hand, AdRGD-CCL19-injection in the immunized mice showed slight increase of tumor-infiltrating T cells compared to treatment using control vector. Collectively, although AdRGD-mediated chemokine gene transduction into established tumors would be very useful for augmentation of tumor-infiltrating immune cells, a combinational treatment that can systemically induce tumor-specific effector T cells is necessary for satisfactory antitumor efficacy.

Female-specific neuroprotection against transient brain ischemia observed in mice devoid of prion protein is abolished by ectopic expression of prion protein-like protein.

This study was designed to examine the function of cellular prion protein and prion protein-like protein/Doppel, in transient ischemia-related neuronal death in the hippocampus. Two different lines of mice devoid of cellular prion protein, Zrch I Prnp(0/0) and Ngsk Prnp(0/0), were used. The former lacks cellular prion protein whereas the latter ectopically expresses prion protein-like protein/Doppel in the brain in the absence of cellular prion protein. Mice were subjected to 10 min-occlusion of the bilateral common carotid arteries with recovery for 14 days. Less than 10% of the pyramidal neurons in the CA1 subfield were degenerated in male and female wild-type mice. In contrast, more than half of the neurons were lost in male Zrch I Prnp(0/0) and Ngsk Prnp(0/0) mice. Such severe neuronal loss was also observed in female Ngsk Prnp(0/0) mice. However, female Zrch I Prnp(0/0) mice showed mild neuronal loss similar to wild-type mice. Flunarizine, a T- and L-type Ca(2+)-channel antagonist, significantly reduced the neuronal loss in female but not in male Ngsk Prnp(0/0) mice. These results indicate that loss of cellular prion protein renders hippocampal neurons susceptible to ischemic insult specifically in male but not female mice and the ectopic expression of prion protein-like protein/Doppel aggravates the ischemic neuronal death in female prion protein-null mice probably via overloading of Ca(2+)-dependent signaling.

Involvement of stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK) in prostaglandin F2alpha-induced heat shock protein 27 in osteoblasts.

We have reported that prostaglandin F2(alpha) (PGF2(alpha)) activates p44/p42 mitogen-activated protein (MAP) kinase in osteoblast-like MC3T3-E1 cells, and that p44/p42 MAP kinase plays a role in the PGF2(alpha)-induced heat shock protein 27 (HSP27). In the present study, we investigated the involvement of stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK), a member of the MAP kinase superfamily, in PGF2(alpha)-induced HSP27 in MC3T3-E1 cells. PGF2(alpha) time dependently induced the phosphorylation of SAPK/JNK. SP600125, a specific inhibitor of SAPK/JNK, markedly reduced the PGF2(alpha)-stimulated HSP27 accumulation. The inhibitory effect of SP600125 was dose dependent in the range between 0.1 and 30 microM. SP600125 reduced the PGF2(alpha)-increased level of HSP27 mRNA. SP600125 suppressed the phosphorylation of SAPK/JNK induced by PGF2(alpha), but did not affect the PGF2(alpha)-induced phosphorylation of p44/p42 MAP kinase. On the other hand, PD98059, a specific inhibitor of the upstream kinase of p44/p42 MAP kinase, which reduced the phosphorylation of p44/p42 MAP kinase stimulated by PGF2(alpha), had little effect on the PGF2(alpha)-induced phosphorylation of SAPK/JNK. These results strongly suggest that SAPK/JNK plays a part in PGF2(alpha)-induced HSP27 in addition to p44/p42 MAP kinase in osteoblasts.

Mechanism of improved gene transfer by the N-terminal stearylation of octaarginine: enhanced cellular association by hydrophobic core formation.

The internalization mechanisms associated with octaarginine and stearyl-octaarginine were investigated using confocal laser microscopy and flow cytometric analysis. Octaarginine is able to translocate through cell membranes in a manner that does not exactly involve the classical endocytic pathways of internalization. However, when a stearyl moiety is attached to the N-terminus of octaarginine, the internalization shifts mainly to an endocytosis-dependent pathway. The transfection efficiency of stearyl-octaarginine was significantly higher than that of octaarginin. To understand the mechanism of the improved gene transfer by the N-terminal stearylation of octaarginine, the gene transfer processes mediated by octaarginine or stearyl-octaarginine were compared. Both octaarginine and stearyl-octaarginine are able to carry plasmid DNA into cells. The amount of plasmid DNA internalized as well as that delivered to the nucleus was higher in the case of stearyl-octaarginine. Even though the internalization mechanisms of octaarginine and stearyl-octaarginine were different, their complexes with plasmid DNA were internalized via the same pathway, presumably, the clathrin-mediated pathway of endocytosis. The results of the atomic force microscopy revealed that stearyl-octaarginine, but not octaarginine, can completely condense the DNA into stable complexes that can be highly adsorbed to the cell surface and subsequently highly internalized. Therefore, using stearylated-octaarginine provided higher internalization of plasmid DNA into cells, due to enhanced cellular association, as well as higher nuclear delivery. The results presented in this study provide a better understanding of the mechanisms of improved transfection using stearylated-octaarginine. The concept of using stearylated peptides may aid in the development of more efficient nonviral gene vectors.

Involvement of stress-activated protein kinase/c-Jun N-terminal kinase in endothelin-1-induced heat shock protein 27 in osteoblasts.

OBJECTIVE: We have reported that endothelin-1 (ET-1) activates p38 mitogen-activated protein (MAP) kinase through protein kinase C in osteoblast-like MC3T3-E1 cells, and that p38 MAP kinase plays a role in the ET-1-induced heat shock protein 27 (HSP27). Recently, we found that stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) is activated by ET-1 in these cells. In the present study, we have investigated the involvement of SAPK/JNK in ET-1-induced HSP27 in MC3T3-E1 cells. METHODS: The concentration of HSP27 in soluble extracts of the cells, the expression of mRNA for HSP27, and the phosphorylation of SAPK/JNK were determined by an enzyme immunoassay, Northern blot analysis, and Western blot analysis respectively. RESULTS: SP600125, a specific inhibitor of SAPK/JNK, markedly reduced ET-1-stimulated HSP27 accumulation. The inhibitory effect of SP600125 was dose dependent in the range between 1 and 50 microM. SP600125 reduced the ET-1-increased level of HSP27 mRNA. Calphostin C and Go 6976, inhibitors of protein kinase C, reduced the ET-1-induced phosphorylation of SAPK/JNK. 12-O-Tetradecanoylphorbol-13-acetate, a direct activator of protein kinase C, induced SAPK/JNK phosphorylation, which was suppressed by SP600125. A combination of SP600125 and p38 MAP kinase inhibitor such as SB203580 and PD169316 additively reduced the ET-1-stimulated accumulation of HSP27. CONCLUSIONS: These results strongly suggest that JNK plays a part in ET-1-induced HSP27 in addition to p38 MAP kinase in osteoblasts.

Enhanced antitumor effect of combined replicative adenovirus and nonreplicative adenovirus expressing interleukin-12 in an immunocompetent mouse model.

For cancer gene therapy, replicative adenovirus is a promising vector to overcome low infectivity and poor gene delivery of nonreplicative adenovirus in vivo, but its therapeutic efficacy is still unsatisfactory because of the limited spread of replicative virus in a solid tumor. Therefore, the combined therapy with other antitumor agents may be necessary. Nonreplicative adenovirus expressing a therapeutic gene may be a promising candidate because E1 proteins expressed by replicative adenovirus would render nonreplicative adenovirus replicative, augmenting a transgene expression. In this study, we first found that mouse hepatoma Hepa 1-6 cells were permissive for the replication and cytopathic effect of human adenovirus, which enabled us to examine the potential of combined replicative adenovirus and nonreplicative adenovirus expressing an immunostimulator in an immunocompetent mouse-syngeneic Hepa 1-6 tumor model. Nonreplicative adenovirus expressing interleukin-12 (AdIL-12) was used as a model. In vitro coinfection of two adenoviruses produced higher concentrations of IL-12 than infection of AdIL-12 alone in this cell line. In vivo experiments with Hepa 1-6 tumors in syngeneic immunocompetent C57BL/6 mice showed higher concentrations of serum IL-12 and greater therapeutic efficacy in the combination therapy than infection of either adenovirus. These data indicate that the combination of replicative adenovirus and nonreplicative adenovirus expressing an immunostimulator appears to be very efficacious for cancer gene therapy.

Age-related changes in brain regional activity during chewing: a functional magnetic resonance imaging study.

Age-related changes in mastication-induced brain neuronal activity have been suggested. However, in humans, little is known about the anatomical regions involved. Using fMRI during cycles of rhythmic gum-chewing and no chewing, we have examined the effect of aging on brain regional activity during chewing in young adult (19-26 yrs), middle-aged (42-55 yrs), and aged (65-73 yrs) healthy humans. In all subjects, chewing resulted in a bilateral increase in the BOLD signals in the sensorimotor cortex, cerebellum, thalamus, supplementary motor area, and insula, and a unilateral increase in the right prefrontal area. In the first three regions, the signal increases were attenuated in an age-dependent manner, whereas, in the right prefrontal area, the converse was seen. The remaining two regions showed no significant differences with ages. These results indicate that chewing causes regional increases in neuronal activity in the brain, some of which are age-dependent.

Terminoside A, a new triterpene glycoside from the bark of Terminalia arjuna inhibits nitric oxide production in murine macrophages.

Terminoside A (1), a new oleanane-type triterpene was isolated from the acetone fraction of the ethanolic extract of stem bark of Terminalia arjuna. The structure was established as olean-1alpha,3beta,22beta-triol-12-en-28-oic acid-3beta-D-glucopyranoside. On the basis of spectral data and chemical reactions, terminoside A, potently inhibited nitric oxide (NO) production and decreased inducible nitric oxide synthase (iNOS) levels in lipopolysaccharide-stimulated macrophages.

Mapping brain region activity during chewing: a functional magnetic resonance imaging study.

Mastication has been suggested to increase neuronal activities in various regions of the human brain. However, because of technical difficulties, the fine anatomical and physiological regions linked to mastication have not been fully elucidated. Using functional magnetic resonance imaging during cycles of rhythmic gum-chewing and no chewing, we therefore examined the interaction between chewing and brain regional activity in 17 subjects (aged 20-31 years). In all subjects, chewing resulted in a bilateral increase in blood oxygenation level-dependent (BOLD) signals in the sensorimotor cortex, supplementary motor area, insula, thalamus, and cerebellum. In addition, in the first three regions, chewing of moderately hard gum produced stronger BOLD signals than the chewing of hard gum. However, the signal was higher in the cerebellum and not significant in the thalamus, respectively. These results suggest that chewing causes regional increases in brain neuronal activities which are related to biting force.