Responses of blood glucose, insulin, glucagon, and Fatty acids to intraruminal infusion of propionate in hanwoo.

This study was carried out to investigate the effects of intraruminal infusion of propionate on ruminal fermentation characteristics and blood hormones and metabolites in Hanwoo (Korean cattle) steers. Four Hanwoo steers (average body wt. 270 kg, 13 month of age) equipped with rumen cannula were infused into rumens with 0.0 M (Water, C), 0.5 M (37 g/L, T1), 1.0 M (74 g/L, T2) and 1.5 M (111 g/L, T3) of propionate for 1 hour per day and allotted by 4×4 Latin square design. On the 5th day of infusion, samples of rumen and blood were collected at 0, 60, 120, 180, and 300 min after intraruminal infusion of propionate. The concentrations of serum glucose and plasma glucagon were not affected (p>0.05) by intraruminal infusion of propionate. The serum insulin concentration at 60 min after infusion was significantly (p<0.05) higher in T3 than in C, while the concentration of non-esterified fatty acid (NEFA) at 60 and 180 min after infusion was significantly (p<0.05) lower in the propionate treatments than in C. Hence, intraruminal infusion of propionate stimulates the secretion of insulin, and decreases serum NEFA concentration rather than the change of serum glucose concentration.

Upregulation of relaxin receptors in the PDL by biophysical force.

OBJECTIVES: We have previously reported that relaxin (Rln) expression from the ovary is upregulated by orthodontic tooth movement. This study was performed to test the hypothesis that Rln family peptides (Rxfps), the G-protein-coupled Rln receptor, is induced in periodontal ligament (PDL) cells to modulate the molecules involved in periodontal tissue remodeling while applying biophysical force. MATERIALS AND METHODS: Rats were implanted with orthodontic appliances to investigate changes to Rxfps in vivo. An in vitro biophysical force analysis was performed to measure the level of Rxfp 1 messenger RNA (mRNA) in primary human PDL cells. RESULTS: The levels of Rxfp 2 transcription and translation increased in a time-dependent manner during tooth movement. Rxfp 2 was localized in the PDL by immunofluorescence. In vitro analyses revealed that the level of Rxfp 1 mRNA in PDL cells increased significantly with both compression and tension force. The levels of matrix metalloproteinase (MMP)-1, MMP-2, interleukin-6, and vascular endothelial growth factor mRNA, which are important for periodontal tissue remodeling, also changed under force application and Rln treatment. CONCLUSIONS: PDL cells responded to Rln to modulate effector molecules for periodontal tissue remodeling by upregulating Rxfps expression under a biophysical force. CLINICAL RELEVANCE: Rln and Rxfps may serve as a PDL turnover molecule complex to control orthodontic tooth movement.

Effects of Coconut Materials on In vitro Ruminal Methanogenesis and Fermentation Characteristics.

The objective of this study was to evaluate the in vitro effects of coconut materials on ruminal methanogenesis and fermentation characteristics, in particular their effectiveness for mitigating ruminal methanogenesis. Fistulated Holstein cows were used as the donor of rumen fluid. Coconut materials were added to an in vitro fermentation incubated with rumen fluid-buffer mixture and timothy substrate for 24 h incubation. Total gas production, gas profiles, total volatile fatty acids (tVFAs) and the ruminal methanogens diversity were measured. Although gas profiles in added coconut oil and coconut powder were not significantly different, in vitro ruminal methane production was decreased with the level of reduction between 15% and 19% as compared to control, respectively. Coconut oil and coconut powder also inhibited gas production. The tVFAs concentration was increased by coconut materials, but was not affected significantly as compared to control. Acetate concentration was significantly lower (p<0.05), while propionate was significantly higher (p<0.05) by addition of the coconut materials than that of the control. The acetate:propionate ratio was significantly lowered with addition of coconut oil and coconut powder (p<0.05). The methanogens and ciliate-associated methanogens in all added coconut materials were shown to decrease as compared with control. This study showed that ciliate-associated methanogens diversity was reduced by more than 50% in both coconut oil and coconut powder treatments. In conclusion, these results indicate that coconut powder is a potential agent for decreasing in vitro ruminal methane production and as effective as coconut oil.

The Effect of Plant Extracts on In-vitro Ruminal Fermentation, Methanogenesis and Methane-related Microbes in the Rumen.

The effect on methanogens attached to the surface of rumen ciliate protozoa by the addition of plant extracts (pine needles and ginkgo leaves) was studied with particular reference to their effectiveness for decreasing methane emission. The plant extracts (pine needles and ginkgo leaves) were added to an in vitro fermentation incubated with rumen fluid. The microbial population including bacteria, ciliated-associated methanogen, four different groups of methanogens and Fibrobacter succinogenes were quantified by using the real-time PCR. Gas profiles including methane, carbon dioxide and hydrogen, and runinal fermentation characteristics were observed in vitro. The methane emission from samples with an addition of individual juices from pine needles, ginkgo leaves and 70% ethanol extract from ginko leaves was significantly lower (p<0.05, 27.1, 28.1 and 28.1 vs 34.0 ml/g DM) than that of the control, respectively. Total VFAs in samples with an addition of any of the plant extracts were significantly lower than that of the control (p<0.05) as well. The order Methanococcales and the order Methanosarcinales were not detected by using PCR in any incubated mixtures. The ciliate-associated methanogens population decreased from 25% to 49% in the plant extacts as compared to control. We speculate that the supplementation of juice from pine needles and ginkgo leaves extract (70% ethanol extract) decreased the protozoa population resulting in a reduction of methane emission in the rumen and thus inhibiting methanogenesis. The order Methanobacteriales community was affected by addition of all plant extracts and decreased to less than the control, while the order Methanomicrobiales population showed an increase to more than that of the control. The F. succinogenes, the major fibrolytic microorganism, population in all added plant extracts was increased to greater than that of the control. In conclusion, pine needles and ginkgo leaves extracts appear to have properties that decrease methanogenesis by inhibiting protozoa species and may have a potential for use as additives for ruminants.

Effects of Supplementing Microbially-fermented Spent Mushroom Substrates on Growth Performance and Carcass Characteristics of Hanwoo Steers (a Field Study).

This study evaluated the effect of dietary supplementation of microbially-fermented spent mushroom substrates (MFSMS) on weight gain, carcass characteristics, and economic efficiency of Hanwoo steers. Highly cellulolytic bacteria (Enterobacter spp. and Bacillus spp.) isolated from spent mushroom substrates (SMS) stacks were inoculated (1% v/v) into the SMS, which was anaerobically fermented and fed to the steers for 12.6 months during the growing and fattening periods. Growing Hanwoo steers were assigned to the control group without supplementation of Microbially-fermented SMS (MFSMS), to a treatment group with 50% of MFSMS (1/2 of the ad libitum group), and to a treatment group with ad libitum access to SMS (the ad libitum group). All the groups were fed the formulated feed and rice straw. The voluntary intake (DM basis) of MFSMS was 1.6 kg/d during the growing period and 1.4 kg/d during the fattening period. The voluntary rice straw intake decreased by 6 to 11%, but the total voluntary DMI increased by 7 to 15% with MFSMS fed. The increased DMI with MFSMS supplementation resulted in a tendency of increased (p = 0.055) live weight gain by 8 to 12% compared with the control group. At slaughtering, the supplementation of MFSMS increased (p<0.05) the ribeye area by an average of 10 cm(2). In conclusion, feeding MFSMS improved growth performance and carcass traits of Hanwoo steers and could successfully replace a part of conventional roughage such as rice straw commonly used in Asian countries.

A false presence of bifid mandibular canals in panoramic radiographs.

OBJECTIVES: This study was performed in order to verify bifid mandibular canals revealed from panoramic radiographic results. METHODS: 1000 panoramic radiographs from dental patients and the panorama, cone beam CT (CBCT) and micro-CT from 40 dry mandibles were examined for bifid mandibular canals. The results were confirmed by a stereoscopic and histological examination of the cross-sectioned mandibles. RESULTS: The prevalence of bifid canals detected from the panoramic radiographs was 0.038. The panoramic radiographs from one dry mandible showed two separate radiolucent mandibular canal-like structures delineated by radio-opaque lines. However, a stereoscopic and histological examination of a cross-section of the mandible showed that only one canal was a true canal containing neurovascular bundles: the other was false, reflecting merely a bony trabecular pattern. CONCLUSIONS: The presence of bifid mandibular canals determined by panoramic radiography should be judged with great caution in relation to dental surgery.

Kurarinol, tyrosinase inhibitor isolated from the root of Sophora flavescens.

It is well known that flavanones, sophoraflavanone G 1, kurarinone 2, and kurarinol 3, from the root of Sophora flavescens, have extremely strong tyrosinase inhibitory activity. This study delineates the principal pharmacological features of kurarinol 3 that lead to inhibition of the oxidation of l-tyrosine to melanin by mushroom tyrosinase (IC(50) of 100 nM). The inhibition kinetics analyses unveil that compounds 1 and 2 are noncompetitive inhibitors. However similar analysis shows kurarinol 3 to be a competitive inhibitor. Compounds 1 and 2 exhibited potent antibacterial activity with 10 microg/disk against Gram-positive bacteria, whereas kurarinol 3 did not ostend any antibacterial activity. Interestingly, kurarinol 3 inhibits production of melanin in S. bikiniensis without affecting the growth of microorganism. It is thus distinctly different from the other tyrosinase inhibitors 1 and 2. In addition, kurarinol 3 manifests relatively low cytotoxic activity (EC(50)>30 microM) compared to 1 and 2. To account for these observations, we conducted molecular modeling studies. These suggested that the lavandulyl group within 3 is instrumental in the interaction with the enzyme. More specifically, the terminal hydroxy function within the lavandulyl group is most important for optimal binding.

An experimental model of ischemia in rabbit hindlimb.

This study was performed to establish an experimental model of ischemia for the investigation of new treatment modality of limb-threatening ischemia. We produced ischemia in the hindlimbs of 8 New Zealand white rabbits. Under general anesthesia, the left femoral artery was exposed, freed, and excised from distal external iliac artery to proximal popliteal and saphenous arteries. And then both hindlimbs were serially examined to assess the ischemia according to the time table until postoperative 6 weeks. We assessed clinical observation, blood pressure, radioisotopic perfusion scan, and angiography. Clinical ischemic changes of the operated feet were observed in 63%. The blood pressure of left calves was measurable on postoperative day 3 (p<0.05, vs preoperative day 2) and then gradually increased to reach a plateau in postoperative week 6. Radioisotopic arterial perfusion showed similar profiles as in blood pressure. Angiography of ischemic hindlimbs demonstrated a few collateral vessels arising from the internal iliac artery with the reconstitution of the posterior tibial artery in postoperative week 2. In postoperative week 6, collaterals remained the same in number. However, these became dilated and tortuous and showed reconstitution in distal hindleg. In conclusion, this is a reproducible, measurable, and economical animal model of hind limb ischemia.

EMF1, a novel protein involved in the control of shoot architecture and flowering in Arabidopsis.

Shoot architecture and flowering time in angiosperms depend on the balanced expression of a large number of flowering time and flower meristem identity genes. Loss-of-function mutations in the Arabidopsis EMBRYONIC FLOWER (EMF) genes cause Arabidopsis to eliminate rosette shoot growth and transform the apical meristem from indeterminate to determinate growth by producing a single terminal flower on all nodes. We have identified the EMF1 gene by positional cloning. The deduced polypeptide has no homology with any protein of known function except a putative protein in the rice genome with which EMF1 shares common motifs that include nuclear localization signals, P-loop, and LXXLL elements. Alteration of EMF1 expression in transgenic plants caused progressive changes in flowering time, shoot determinacy, and inflorescence architecture. EMF1 and its related sequence may belong to a new class of proteins that function as transcriptional regulators of phase transition during shoot development.

Characterization of MADS box genes from hot pepper.

The cDNA clone, CanMADS1, was isolated from young flower buds of the hot pepper (Capsicum annuum L.) by screening a cDNA library using the OsMADS1 rice MADS-box gene as a probe. We used a yeast two-hybrid screening method to investigate interaction partners of the protein product of CanMADS1. A MADS-box gene, CanMADS6, was isolated from young flower buds using the region containing the K domain and 15 amino acid residues of the C-terminal region of CanMADS1 as a bait. CanMADS1 and CanMADS6 showed high amino acid sequence similarities to members of the AGL2 subfamily and the SQUA subfamily, respectively. CanMADS1 transcript was expressed in flower buds and fruits, and the transcription signal was the strongest in the stage of the fruit set (2 d after anthesis). CanMADS6 showed the same expression pattern as CanMADS1. CanMADS1 and CanMADS6 were not expressed in leaves. These results suggest that a regulatory role for flower and fruit development of the hot pepper may be accomplished through an interaction of the protein products of the two MADS-box genes, CanMADS1 and CanMADS6.

Antibacterial activity of S-methyl methanethiosulfinate and S-methyl 2-propene-1-thiosulfinate from Chinese chive toward Escherichia coli O157:H7.

S-Methyl methanethiosufinate (1) and S-methyl 2-propene-1-thiosulfinate (2) were easily seperated from Chinese chive (Allium tuberosum L.) using simple column chromatography. Both compounds showed significant antibacterial activities against E. coli O-157:H7 including spoilage microorganism in food. Structural assignment was based on Mass and NMR-spectroscopic methods.

Systemic induction of a Phytolacca insularis antiviral protein gene by mechanical wounding, jasmonic acid, and abscisic acid.

We have isolated a gene encoding a ribosome-inactivating protein (RIP) from Phytolacca insularis, designated as P. insularis antiviral protein 2 (PIP2). The PIP2 gene contained an open reading frame encoding a polypeptide of 315 amino acids. The deduced amino acid sequence of PIP2 was similar to those of other RIPs from Phytolacca plants. Recombinant PIP2 was expressed in Escherichia coli and was used to investigate its biological activities. Recombinant PIP2 inhibited protein synthesis in rabbit reticulocyte lysate by inactivating ribosomes through N-glycosidase activity. It also exhibited antiviral activity against tobacco mosaic virus (TMV). Expression of the PIP2 gene was developmentally regulated in leaves and roots of P. insularis. Furthermore, expression of the PIP2 gene was induced in leaves by mechanical wounding. The wound induction of the PIP2 gene was systemic. Expression of the PIP2 gene also increased in leaves in a systemic manner after treatment with jasmonic acid (JA) and abscisic acid (ABA), but not with salicylic acid (SA). These results imply that plants have employed the systemic synthesis of the defensive proteins to protect themselves more efficiently from infecting viruses.

Truncated form of importin alpha identified in breast cancer cell inhibits nuclear import of p53.

Disruption of the function of tumor suppressor proteins occasionally can be dependent on their subcellular localization. In about 40% of the breast cancer tissues, p53 is found in the cytoplasm as opposed to the nucleus, where it resides in normal breast cells. This means that the regulation of subcellular location of p53 is an important mechanism in controlling its function. The transport factors required for the nuclear export of p53 and the mechanisms of their nuclear export have been extensively characterized. However, little is known about the mechanism of nuclear import of p53. p53 contains putative nuclear localization signals (NLSs) which would interact with a nuclear transport factor, importin alpha. In this report we demonstrate that importin alpha binds to NLSI in p53 and mediates the nuclear import of p53. Reverse transcriptase-polymerase chain reaction and sequencing analyses showed that a truncated importin alpha deleted the region encoding the putative NLS-binding domain of p53, suggesting that it could not bind to NLSs of p53 proteins. Binding of importin alpha to p53 was confirmed by using yeast two-hybrid assay. When expressed in CHO-K1 cells, the truncated importin alpha predominantly localized to the cytoplasm. In truncated importin alpha expressing cells, p53 preferentially localized to cytoplasmic sites as well. A significant increase in the p21(waf1/cip1) mRNA level and induction of apoptosis were also observed in importin alpha overexpressing cells. These results strongly suggest that importin alpha functions as a component of the NLS receptor for p53 and mediates nuclear import of p53.

Two rice MADS domain proteins interact with OsMADS1.

OsMADS1 is a MADS box gene controlling flower development in rice. In order to learn more about the function of OsMADS1, we searched for cellular proteins interacting with OsMADS1 employing the yeast two-hybrid system. Two novel proteins with MADS domains, which were named OsMADS14 and OsMADS15, were isolated from a rice cDNA library. OsMADS14 and -15 are highly homologous to the maize MADS box gene ZAP1 which is an orthologue of the floral homeotic gene APETALA1 (AP1). Interactions among the three MADS domain proteins were confirmed by in vitro experiments using GST-fused OsMADS1 expressed in Escherichia coli and in vitro translated proteins of OsMADS14 and -15. We determined which domains in OsMADS1, -14, and -15 were required for protein-protein interaction employing the two-hybrid system and pull-down experiments. While the K domain was essential for protein-protein interaction, a region preceded by the K domain augmented this interaction. Interestingly, the C-terminal region of OsMADS1 functioned as a transcriptional activation domain in yeast and mammalian cells, while, on the other hand, the C domains of OsMADS14 and -15 exhibited only very weak transcriptional activator functionality, if any at all.

A fast fractal decoding algorithm based on the selection of an initial image.

In this correspondence, we show that the number of iterations required for the convergence of the fractal image decoding algorithm can be reduced by selecting a suitable initial image. We consider fractal decoding to have two components, namely, "DC" and "AC". Our initial image is an approximation of the attractor of DC decoding, which is a good estimation of the "range-averaged" image, i.e., the image obtained by replacing all pixel intensities in a given block by the mean value of the block. From the simulation, it is demonstrated that the decoding speed is greatly improved.

Co-administration of toluene and xylene antagonized the testicular toxicity but not the hematopoietic toxicity caused by ethylene glycol monoethyl ether in Sprague-Dawley rats.

Occupational painters are exposed to ethylene glycol monoethyl ether (EGEE), a widely used emulsifying solvent known to cause testicular degeneration and bone marrow depression, together with toluene (TOL) and xylene (XYL) as a mixture. In the previous study (Chung et al., Tox. Lett. 104:143, 1999), testicular atrophy caused by EGEE (200 mg/kg) was shown to be antagonized by co-administration of TOL (250 mg/kg) and XYL (500 mg/kg). This study was conducted to provide histological support for the previously observed antagonistic protective effect of TOL + XYL on EGEE inducible testicular toxicity and to determine whether a similar antagonistic effect can be demonstrated against the EGEE derived hematopoietic toxicity. Compared to the extent of seminiferous tubule degeneration caused by EGEE (150 mg/kg, six times per week for 4 weeks), testes of rats given co-administration of TOL (250 mg/kg) + XYL (500 mg/kg) showed dramatically reduced tubular degeneration. Hyperplasia of Leydig cells in the interstitium was observed in both EGEE and EGEE + TOL + XYL-treated rats. Although a minimal dose of EGEE causing testicular atrophy was used, WBC and platelet counts were decreased significantly. In the TOL + XYL-treated control group, the WBC and platelet counts were not decreased. However, the bone marrow depression caused by EGEE was not reversed by the combined administration of TOL + XYL. In all experimental groups (EGEE alone, TOL + XYL, EGEE + TOL + XYL), plasma levels of creatinine and alkaline phosphatase were significantly decreased. In addition to the marked testicular atrophy, EGEE also decreased the weights of adrenal glands and epididymis. In conclusion, while the testicular degeneration caused by EGEE was antagonized by TOL + XYL, the EGEE derived hematopoietic suppression was not reversed.

Analysis of the C-terminal region of Arabidopsis thaliana APETALA1 as a transcription activation domain.

APETALA1 (AP1) of Arabidopsis thaliana is a transcription factor controlling flower development. AP2 is a member of the MADS (MCM1, AGAMOUS, DEFICIENS, SRF) superfamily, which plays important roles in differentiation in plants and animals. MADS domains, which function most importantly in DNA binding, are found in all major eukaryotic kingdoms. In plants, MADS domain-containing proteins also possess a region of moderate sequence similarity named the K domain, which is involved in protein-protein interaction. Little is known about the function of a third, highly variable, domain designated the C domain, as it resides at the C terminus of the MADS proteins of plants. Here we report that the C-terminal domain of Arabidopsis thaliana AP1 and its homologues perform a transcriptional activation function. The C-terminal region of AP1 is composed of at least two separable transcriptional activation domains that function synergistically.

Determination of the motif responsible for interaction between the rice APETALA1/AGAMOUS-LIKE9 family proteins using a yeast two-hybrid system.

A MADS family gene, OsMADS6, was isolated from a rice (Oryza sativa L.) young flower cDNA library using OsAMDS1 as a probe. With this clone, various MADS box genes that encode for protein-to-protein interaction partners of the OsMADS6 protein were isolated by the yeast two-hybrid screening method. On the basis of sequence homology, OsMADS6 and the selected partners can be classified in the APETALA1/AGAMOUS-LIKE9 (AP1/AGL9) family. One of the interaction partners, OsMADS14, was selected for further study. Both genes began expression at early stages of flower development, and their expression was extended into the later stages. In mature flowers the OsMADS6 transcript was detectable in lodicules and also weakly in sterile lemmas and carpels, whereas the OsMADS14 transcript was detectable in sterile lemmas, paleas/lemmas, stamens, and carpels. Using the yeast two-hybrid system, we demonstrated that the region containing of the 109th to 137th amino acid residues of OsMADS6 is indispensable in the interaction with OsMADS14. Site-directed mutation analysis revealed that the four periodical leucine residues within the region are essential for this interaction. Furthermore, it was shown that the 14 amino acid residues located immediately downstream of the K domain enhance the interaction, and that the two leucine residues within this region play an important role in that enhancement.

Identification of a rice APETALA3 homologue by yeast two-hybrid screening.

A cDNA clone OsMADS16 was isolated from the rice young inflorescence cDNA expression library by the yeast two-hybrid screening method with OsMADS4 as bait. We have previously shown that the OsMADS4 gene is a member of the PI family and that the MADS-box gene is involved in controlling development of the second and third whorls of rice flowers. The sequence comparison indicated that OsMADS16 belongs to the AP3 family. The OsMADS16 protein contains a PI-derived motif, FAFRVVPSQPNLH, that is a conserved sequence in AP3 family genes at the C-terminal region. In addition, OsMADS16 contains a paleoAP3 motif, YGGNHDLRLG, downstream of the PI-derived motif. The paleoAP3 motif is a consensus sequence in the C-terminal region of the AP3 family genes of lower eudicot and magnolid dicot species. RNA blot analysis showed that the OsMADS16 gene was expressed in the second and third whorls, whereas the OsMADS4 transcripts were present in the second, third, and fourth whorls. These expression patterns of the OsMADS16 and OsMADS4 genes are very similar to those of AP3 and PI, respectively. In the yeast two-hybrid system, OsMADS4 interacted only with OsMADS16 among several rice MADS genes investigated, suggesting that OsMADS4 and OsMADS16 function as a heterodimer in specifying sepal and petal identities. The OsMADS16 protein displayed transcription activation ability in yeast, whereas AP3 did not. It was also shown in yeast that OsMADS16 interacted with PI whereas OsMADS4 did not interact with AP3. These differences between OsMADS16 and AP3 indicate that the functions of the AP3 family genes of monocots and dicots diverged during molecular evolution processes of the B function genes. Deletion analysis showed that the 155-200 amino acid region of the OsMADS16 protein plays an important role in the transcription activation ability.