Effects of sex control and twinning on economic optimization of culling cows in Japanese Black cow-calf production systems

The effects of sex control and twinning techniques on determination of optimal culling parity of cows in beef cow-calf production systems were deterministically analyzed using a herd model simulation. The model simulated the annualized net revenue as an economic indicator during the whole life cycle of a cow. Biological factors (survivability, growth, reproduction, and feed requirements) and economic factors (returns from sales of live calves and cows' carcasses and production costs) were included in the model. Some biological and economic parameters relating to these factors were altered from a base condition in order to adapt the production systems with sex control and twinning techniques. Based on the model, early culling was optimal for all production systems when biological efficiency was used as an indicator of production; however, later culling was optimal for single production, but slightly earlier culling was optimal for twin production, when annualized net revenue was evaluated. The introduction of sex control did not greatly affect the determination of the optimal culling parity of cows. When production included the sex control, female sexing increased biological efficiency, whereas male sexing increased annualized net revenue. In the present beef cow-calf production circumstances in Japan, introduction of sex control did not have economically appreciable effects, but twinning was economically beneficial. For production involving sex control, improvement in the conception rate per mating and/or reduction of technical cost were required for this technology to be profitable.     

Accelerating Effect of Soy Peptides Containing Collagen Peptides on Type I and III Collagen Levels in Rat Skin

Two weeks of feeding soy peptides containing 2% collagen peptides increased the levels of type I and III tropocollagen and their mRNAs. In contrast, the diet did not increase the mRNA levels of rat hyaluronan synthases, serine palmitoyltransferase (the rate-limiting enzyme of ceramide synthesis), and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (the key enzyme of cholesterol synthesis). These results suggest that feeding of soy peptides with collagen peptides specifically enhanced the tropocollagen level in the skin.     

Structure–activity relationship study of pyrimido[1,2-c][1,3]benzothiazin-6-imine derivatives for potent anti-HIV agents

3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine (PD 404182) is an antiretroviral agent with submicromolar inhibitory activity against human immunodeficiency virus-1 (HIV-1) and HIV-2 infection. In the current study, the structure–activity relationships of accessory groups at the 3- and 9-positions of pyrimido[1,2-c][1,3]benzothiazin-6-imine were investigated for the development of more potent anti-HIV agents. Several different derivatives containing a 9-aryl group were designed and synthesized using Suzuki–Miyaura cross-coupling and Ullmann coupling reactions. Modification of the m-methoxyphenyl or benzo[d][1,3]dioxol-5-yl group resulted in improved anti-HIV activity. In addition, the 2,4-diazaspiro[5.5]undec-2-ene-fused benzo[e][1,3]thiazine derivatives were designed and tested for their anti-HIV activities. The most potent 9-(benzo[d][1,3]dioxol-5-yl) derivative was two–threefold more effective against several strains of HIV-1 and HIV-2 than the parent compound, PD 404182.     

Analysis of growth patterns in purebred Kambing Katjang goat and its crosses with the German Fawn

The objective of this study was to investigate growth patterns of goats utilizing data from a crossbreeding program involving the exotic German Fawn (GF) and the indigenous Kambing Katjang (KK) goats. Growth curve models and growth curve parameters were compared and analyzed for different genotypes and litter types. A total of 20,393 weight–age data from 208 female goats belonging to various crossbreeding genotypes were individually fitted to four growth curve models (Brody, Bertalanffy, Gompertz and Logistic). The goodness of fit was highest in the Brody model in most cases. A comparison of R² among genotypes showed that they were highest for KK. There were no significant differences of genotypes for estimated mature weight in the Brody model. The estimated mature weights for KK were significantly lower (P < 0.05) than for GF × KK (F₁), backcrosses with 75% GF genes (BC) and F₁ × F₁ (F₂) in the other models. The correlations between estimated mature weights and the maturing rates were lowest for BC. The genotype significantly (P < 0.01) affected the age at the constant degree of maturity (67% and 90% of mature weight) in all models. The BC genotype was the youngest at maturity and KK the oldest. All models well expressed the growth pattern of the target animals when they were older than 2.5 years of age. The results from the present study showed that the growth pattern may be altered by crossbreeding of KK with the GF breed.     

Identification of novel non-peptide CXCR4 antagonists by ligand-based design approach

The design and synthesis of novel non-peptide CXCR4 antagonists is described. The peptide backbone of highly potent cyclic peptide-based CXCR4 antagonists was entirely replaced by an indole framework, which was expected to reproduce the disposition of the key pharmacophores consistent with those of potential bioactive conformations of the original peptides. A structure–activity relationship study on a series of modified indoles identified novel small-molecule antagonists having three pharmacophore functional groups through the appropriate linkers.     

Correlation between torpor frequency and capacity for non-shivering thermogenesis in the Siberian hamster (Phodopus sungorus)

We investigated the correlation between torpor frequency and capacity for non-shivering thermogenesis (NST) in Siberian hamsters (Phodopus sungorus) during 25 weeks of acclimation to cold and short days. We hypothesized that torpor use is conditioned on the development of brown adipose tissue (BAT) capacity for NST. We found that (1) the degree of noradrenaline (NA)-induced hyperthermia was positively correlated with torpor frequency and its length and depth, and (2) the maximum response to NA occurred at the time of day when hamsters naturally arouse from torpor. The present study quantifies the correlation between torpor frequency and NST capacity and we suggest that a well-developed NST capacity is a prerequisite for the occurrence of torpor.     

Complex formation of amphotericin B in sterol-containing membranes as evidenced by surface plasmon resonance

Amphotericin B (AmB) is a membrane-active antibiotic that increases the permeability of fungal membranes. Thus, the dynamic process of its interaction with membranes poses intriguing questions, which prompted us to elaborate a quick and reliable method for real-time observation of the drug's binding to phospholipid liposomes. We focused on surface plasmon resonance (SPR) and devised a new modification method of sensor chips, which led to a significant reduction in the level of nonspecific binding of the drug in a control lane. With this method in hand, we examined the affinity of AmB for various membrane preparations. As expected, AmB exhibited much higher affinity for sterol-containing palmitoyloleoylphosphatidylcholine membranes than those without sterol. The sensorgrams recorded under various conditions partly fitted theoretical curves, which were based on three interaction models. Among those, a two-state reaction model reproduced well the sensorgram of AmB binding to an ergosterol-containing membrane; in this model, two states of membrane-bound complexes, AB and AB*, are assumed, which correspond to a simple binding to the surface of the membrane (AB) and formation of another assembly in the membrane (AB*) such as an ion channel complex. Kinetic analysis demonstrated that the association constant in ergosterol-containing POPC liposomes is larger by 1 order of magnitude than that in the cholesterol-containing counterpart. These findings support the previous notion that ergosterol stabilizes the membrane-bound assembly of AmB.     

Development of a microbioreactor for glycoconjugate synthesis

A microbioreactor immobilized with a synthase-type mutant enzyme, Endo-M-N175Q (glycosynthase) of endo-β-N-acetylglucosaminidase derived from Mucor hiemalis (Endo-M), was constructed and used for glycoconjugate synthesis. The transglycosylation was performed with a reaction mixture containing an oxazoline derivative of sialo complex-type glycoside (SG), which was prepared from a sialo complex-type glycopeptide SGP derived from hen egg yolk, as a glycosyl donor and N-Fmoc-N-acetylglucosaminyl-l-asparagine [Fmoc-Asn(GlcNAc)-OH] as an acceptor. The reaction mixture was injected into a glycosynthase microbioreactor at a constant flow rate. Highly efficient and nearly stoichiometric transglycosylation occurred in the microbioreactor, and the transglycosylation product was eluted from the other end of the reactor. The glycosynthase microbioreactor was stable and could be used repeatedly for a long time.     

Regulation of RhoA Signaling by the cAMP-dependent Phosphorylation of RhoGDIα

RhoA plays a pivotal role in regulating cell shape and movement. Protein kinase A (PKA) inhibits RhoA signaling and thereby induces a characteristic morphological change, cell rounding. This has been considered to result from cAMP-induced phosphorylation of RhoA at Ser-188, which induces a stable RhoA-GTP-RhoGDIα complex and sequesters RhoA to the cytosol. However, few groups have shown RhoA phosphorylation in intact cells. Here we show that phosphorylation of RhoGDIα but not RhoA plays an essential role in the PKA-induced inhibition of RhoA signaling and in the morphological changes using cardiac fibroblasts. The knockdown of RhoGDIα by siRNA blocks cAMP-induced cell rounding, which is recovered by RhoGDIα-WT expression but not when a RhoGDIα-S174A mutant is expressed. PKA phosphorylates RhoGDIα at Ser-174 and the phosphorylation of RhoGDIα is likely to induce the formation of a active RhoA-RhoGDIα complex. Our present results thus reveal a principal molecular mechanism underlying G_s/cAMP-induced cross-talk with G_q/G₁₃/RhoA signaling.