Changes in Plasma Progesterone Levels in the Caudal Vena Cava and the Jugular Vein and Luteinizing Hormone Secretion Pattern After Feeding in Lactating and Non-lactating Dairy Cows

The present study was designed to assess progesterone profiles at the secreted (caudal vena cava) and circulating levels (jugular vein) and luteinizing hormone (LH) secretion pattern in lactating and non-lactating cows with reference to feeding. Four lactating and four non-lactating cycling Holstein cows were examined. Blood samples were collected simultaneously from the caudal vena cava (via a catheter inserted from the coccygeal vein) and the jugular vein every 15 min for 12 h (0500–1700 h) during the functional luteal phase. Cows were fed 50% of the daily diet 6 h after the start of blood sampling. During the 12-h sampling period, mean progesterone concentrations in the caudal vena cava did not differ between lactating and non-lactating cows (49.0 ± 2.9 and 53.3 ± 3.7 ng/ml; mean ± SE), whereas mean progesterone concentrations in the jugular vein in lactating cows were higher than those in non-lactating cows (6.4 ± 0.1 and 5.6 ± 0.1 ng/ml, P < 0.001). Lactating cows had a higher frequency of LH pulses than non-lactating cows (7.0 ± 0.7 and 4.3 ± 0.9 pulses/12 h, P<0.05). The influence of feeding was not observed on LH profiles but was observed on progesterone profiles in both veins. Progesterone concentrations in the caudal vena cava increased after feeding in both groups. Progesterone concentrations in the jugular vein decreased after feeding in lactating cows but not in non-lactating cows. These results indicate the difference in feeding-related changes in progesterone dynamics between lactating and non-lactating cows.     

Insect nicotinic acetylcholine receptors: neonicotinoid binding site specificity is usually but not always conserved with varied substituents and species

The diversity of neonicotinoid insecticides acting as insect nicotinic acetylcholine (ACh) receptor (nAChR) agonists is illustrated by imidacloprid (IMI) with chloropyridinylmethyl (CPM) and N-nitroimine substituents, dinotefuran (DIN) with tetrahydrofurylmethyl (TFM) and N-nitroimine moieties, and acetamiprid (ACE) with CPM and N-cyanoimine groups. These three neonicotinoids are used here as radioligands to test the hypothesis that they all bind to the same site in the same way in both fruit flies (Drosophila melanogaster) and a leafhopper pest (Homalodisca coagulata): that is, neonicotinoid binding site specificity is conserved in the insect nAChRs. Multiple approaches show that [3H]IMI and [3H]ACE interact with an identical site in both species. However, although [3H]DIN binds with high affinity in both insects, its pharmacological profile in Homalodisca is surprisingly unique, with high sensitivity to some TFM-containing compounds and ACh. The TFM moiety of DIN may bind in a different orientation compared to the CPM group of IMI and ACE.     

Metabolism of N-[(R)-1-(2,4-dichlorophenyl)ethyl]-2-cyano-3,3-dimethylbutanamide (Delaus, S-2900) and its isomer, N-[(S)-1-(2,4-dichlorophenyl)ethyl]-2-cyano-3,3-dimethylbutanamide (S-2900S), in rats. 1. Identification of metabolites in feces and urine

Rats were orally dosed with a 1:1 diastereomixture of N-[(R)-1-(2,4-dichlorophenyl)ethyl]-2-cyano-3,3-dimethylbutanamide (Delaus, S-2900) and N-[(S)-1-(2,4-dichlorophenyl)ethyl]-2-cyano-3,3-dimethylbutanamide (S-2900S), both labeled with 14C, at 200 mg/kg/day for 5 consecutive days, and 16 metabolites in urine and feces were purified by a combination of several chromatographic techniques. The chemical structures of all isolated metabolites were identified by spectroanalyses (NMR and MS). Several of them were unique decyanated and/or cyclic compounds (lactone, imide, cyclic amide, cyclic imino ether forms). Major biotransformation reactions of the mixture of S-2900 and S-2900S in rats are proposed on the basis of the metabolites identified in this study.     

Application of the vibration method with additional mass to timber guardrail beams

This study examined whether or not weight, density, and Young’s modulus can be accurately measured by vibration test without weighing beams for timber guardrails. Bending vibration tests with and without the concentrated mass were performed on small clear round bars without the pith of spruce and cedar and on actual size round bars with the pith of cedar for the timber guardrail. The following results were obtained. The vibration method with additional mass could be applied to the round bar as well as the rectangular bar. It is possible that resonance frequency was decreased by the sawn split in the horizontal tapping. It is believed that the free ends condition is easier to realize than the fixed ends condition for cross beams for timber guardrails. The weight of the cross beam for the timber guardrail could be accurately estimated by the vibration method with additional mass under several testing conditions.     

5-caffeoylquinic acid and caffeic acid down-regulate the oxidative stress- and TNF-alpha-induced secretion of interleukin-8 from Caco-2 cells

Although chlorogenic acid (CHA) easily reaches a millimolar level in the gastrointestinal tract because of its high concentration in coffee and fruits, its effects on intestinal epithelial cells have been little reported. We investigated in this study the down-regulative effects of 5-caffeoylquinic acid (CQA), the predominant isomer of CHA, on the H(2)O(2-) or TNF-alpha-induced secretion of interleukin (IL)-8, a central pro-inflammatory chemokine involved in the pathogenesis of inflammatory bowel diseases, in human intestinal epithelial Caco-2 cells. After the cells had been pre- and simultaneously treated with CQA, the oversecretion of IL-8 and overexpression of its mRNA induced by H(2)O(2) were significantly suppressed in a dose-dependent manner in the range of 0.25-2.00 mmol/L. We further found that a metabolite of CQA, caffeic acid (CA), but not quinic acid, significantly inhibited the H(2)O(2)-induced IL-8 secretion and its mRNA expression in the same dose-dependent manner. Both CQA and CA suppressed the TNF-alpha-induced IL-8 secretion as well. Caffeic acid at 2.00 mmol/l was able to absolutely block the H(2)O(2)- or TNF-alpha-induced oversecretion of IL-8 in Caco-2 cells. However, CQA and CA did not suppress the TNF-alpha-induced increase in the IL-8 mRNA expression, indicating that the suppressive mechanisms are different between TNF-alpha-induced and H(2)O(2)-induced IL-8 production models. These results suggest that the habit of drinking coffee and/or eating fruits with a high CHA content may be beneficial to humans in preventing the genesis of inflammatory bowel diseases.     

Encapsulating peritoneal sclerosis associated with abnormal liver development in a young dog

A 6-month-old male miniature pinscher dog developed chronic ascites, formation of fibrous membrane covering the abdominal organs, and numerous adhesions between the intestinal loops. The membrane and adhesions were surgically removed twice, but the dog died 1 month after initial presentation. Necropsy revealed recurrence of the membrane and intestinal adhesions. The fibrous membrane was composed of a thick layer of mature collagenous connective tissue, covered by immature collagenous connective tissue with mild lymphoplasmacytic infiltration, prominent neovascularization, and fibrin exudation. Similar fibrotic lesions were observed in the serosa of the liver, spleen, stomach and intestines. These findings are consistent with encapsulating peritoneal fibrosis reported in humans and dogs. The dog also had a maldeveloped liver, which is characterized by disorganized hepatic lobules and disarranged hepatic cords.