Previous studies have indicated that intraruminal infusions of acetate and propionate condition flavour preference in sheep. Three experiments were conducted to evaluate and compare the ...preference-reinforcing effects of postabsorptive acetate and propionate. Eight wethers were used in Experiment 1, and a different eight wethers were used in Experiment 2 and 3. In Experiment 1, wethers were divided into two groups, and a half of each group (
n
=
2) was given clove-flavoured straw and the other half was given cardamom-flavoured straw on odd-numbered days during a 12-d conditioning period. During straw ingestion, wethers in one group received intramesenteric infusion of sodium propionate (0.56
mmol/kg) and the other group received saline infusion. On even-numbered days, flavours and infusate were switched, so that each group received a new flavour and a new infusate. When wethers were offered a choice between the two flavoured straw, they preferred (
P
<
0.01) the flavoured straw that had been paired with propionate infusion. In Experiment 2 and 3, two trials were conducted using four animals in each trial. In Experiment 2, wethers were given clove-flavoured (
n
=
2) or nutmeg-flavoured (
n
=
2) straw paired with intramesenteric infusion of sodium acetate (1.69 and 0.85
mmol/kg in Trial 1 and 2, respectively) on odd-numbered days and the other flavoured straw paired with saline infusion on even-numbered days during a 10-d conditioning period. In subsequent two-choice tests, wethers in Trial 1, but not in Trial 2, showed a preference (
P
<
0.05) for the flavoured straw paired with the acetate infusion. Wethers used in Trial 2 were then given 10 additional days of conditioning with intrajugular infusion of 1.69
mmol/kg of sodium acetate and saline, but preferences for the flavour paired with acetate infusion were not developed. In Experiment 3, wethers were given fennel-flavoured (
n
=
2) or nutmeg-flavoured (
n
=
2) straw paired with sodium propionate infusion (1.69 and 0.96
mmol/kg in Trial 1 and 2, respectively) into the ruminal vein on odd-numbered days and the other flavoured straw paired with saline infusion on even-numbered days during a 10-d conditioning period. In subsequent two-choice tests, wethers in Trial 1 tended to prefer (
P
<
0.10) the flavoured straw paired with propionate infusion to that with acetate infusion. In Trial 2, wethers avoided nutmeg-flavoured straw more than fennel-flavoured straw, but the intake of each flavoured straw tended to be higher (
P
<
0.10) when it was paired with propionate. These results suggest that acetate and propionate generate preference-reinforcing signals in the portal-hepatic area, but the signal generated by acetate is weaker than that by propionate.
Objectives The objective of this report is to elucidate the feasibility of the frozen elephant trunk technique as a one-stage operation for extensive arteriosclerotic aneurysms and to investigate the ...long-term durability and efficacy of this procedure from our 11 years of experience. Methods The subjects were 58 consecutive patients who electively received the frozen elephant trunk technique for arteriosclerotic aneurysms involving the aortic arch and the descending aorta between September 1997 and September 2008. Concomitant procedures included 15 coronary artery bypass grafts, 2 aortic valve replacements, 1 aortic root replacement, and 3 maze procedures. The stent graft was delivered to the seventh thoracic vertebra level (Th7) in 22, Th8 in 26, Th9 in 8, and Th10 in 2 patients. Cerebrospinal fluid drainage was administered preoperatively in 10 (17.2%) patients. Results Operative mortality within 30 days was 0 of 58. There was 1 in-hospital death. Perioperative morbidity included strokes and spinal cord injury in 2 (3.4%) patients each. During the mean follow-up period of 54.2 ± 36.9 months, there were 9 (15.5%) late deaths, and 7 (12.1%) patients required additional intervention. The 8-year survival was 65.5%, the overall 8-year aortic event free survival was 72.8%, and the 8-year event free survival on the site of the stent graft was 94.8%. A follow-up computed tomographic image was available for 86.2% (50/58) of patients who survived longer than 6 months. The size of the aneurysm increased in 1 (2.0%) patient, was not changed in 6 (12.0%) patients, shrank in 34 (68.0%) patients, and was obliterated in 9 (18.0%) patients. Conclusions The frozen elephant trunk for extensive aortic aneurysms had long-term durability and efficacy and might become the alternative treatment for extended aortic replacement.
Objective The operative strategies for retrograde acute type A aortic dissection with a primary intimal tear remain controversial because resection of an intimal tear via a median sternotomy is ...difficult. We evaluated the frozen elephant trunk technique for treating this type of aortic dissection. Methods The frozen elephant trunk technique was used for acute retrograde type A aortic dissection with a primary intimal tear in the descending aorta in 25 consecutive patients (16 men, 9 women; median age, 64 years) seen between 1997 and 2011 at the Hiroshima City Asa Hospital. Three patients had Marfan syndrome. Fourteen patients had ischemia of the lower half of the body, 2 had stroke, 3 had coronary ischemia, and 10 had pericardial tamponade. Results There were no hospital deaths. Postoperative complications occurred in 2 patients, including stroke and mediastinitis. Two late deaths occurred over a median follow-up period of 58 months (12-169 months), one caused by stroke and the other by colon cancer. Two patients needed additional operations: one required a second operation for descending aorta replacement because of ulceration caused by the stent graft, and the other required an endovascular stent graft because of dilatation of the descending aorta. Computed tomography follow-up scans revealed that the false lumen was completely thrombosed and obliterated in all 25 patients with stent grafts. Conclusions The frozen elephant trunk technique for retrograde type A aortic dissection yielded acceptable outcomes, despite the high preoperative morbidity, and might improve the prognosis of dissection.
In rodents, intracerebroventricular oxytocin administration attenuated hypothalamo-pituitary-adrenal (HPA) responses and anxiety behavior during stress. We examined the effects of ...intracerebroventricular injection of oxytocin on isolation-induced stress responses in cattle. In a methodological test, we determined the dosage of oxytocin applied in a main test which did not induce an increase in plasma cortisol concentration or stereotyped behavior. In a main test, 5 steers aged from 199 to 250 days were assigned to the following three treatments randomly: T1, no isolation after injection of 200 microl of artificial cerebrospinal fluid (aCSF); T2, isolation after aCSF injection; and T3, isolation after 0.5 microg of oxytocin in 200 microl aCSF injection. The isolation was conducted by leaving the experimental steer alone in its stall for one hour while its peers were taken outside. In T2, the isolation induced a rapid increase in plasma cortisol concentration. The maximum %-changes from the pre-isolation value were significantly attenuated by oxytocin injection (T2 vs. T3, p0.05). The isolation also induced an increase in the frequency (number of occurrences/1 hr isolation) of vocalizations and body orientation changes, and a decrease in the percentage of time spent lying and ruminating. The effect of oxytocin on these behavioral responses to isolation was not apparent. These results indicate that intracerebroventricularly injected oxytocin at low dose attenuated the cortisol response to isolation in steers while the effect on behavior was very small in this experimental condition.
Two neuropeptides, neuropeptide B (NPB) and prolactin-releasing peptide (PrRP), have been suggested to play important roles in control of the hypothalamic-pituitary-adrenal (HPA) axis in rodents. The ...aim of the present study was to clarify the central actions of NPB or PrRP in sheep. Ovariectomized ewes were surgically implanted with a cannula directed to the lateral ventricle. They received intracerebroventricular (icv) administration of 400 microl of artificial cerebrospinal fluid, NPB (0.05. 0.5 or 5 nmol). PrRP (0.5, 5 or 50 nmol) or corticotropin-releasing hormone (CRH, 0.5 or 5 nmol) through the cannula, and blood samples were taken 30 and 0 min prior to and 15, 30, 60 and 90 min after the injection. Cortisol concentrations in plasma were determined by enzyme immunoassay. Administration of 0.5 nmol NPB resulted in a significant increase in the cortisol concentration compared with the vehicle control, whereas the cortisol concentration after lower or higher doses of NPB did not differ from the control value. Thus, an icv injection of NPB produced a bell-shaped dose-response of cortisol concentration. Administration of PrRP had no significant effect on the cortisol concentrations at any dose examined. Icv injection of CRH dose-dependently increased plasma cortisol concentrations. These results demonstrate that central NPB stimulates cortisol secretion, suggesting that this neuropeptide plays some roles in control of the HPA axis in sheep. On the other hand, unlike its role in rodents, PrRP is unlikely to be involved in control of the HPA axis in this species.
Carbon nitride films have been synthesized by using several processes of film deposition techniques including plasma-CVD, sputtering and ion-beam deposition, etc., according to outstanding properties ...of the super-hard cubic or beta-type C
3N
4 compound. We also prepared the carbon nitride films with magnetically enhanced plasma ion-plating method. The carbon nitride films were deposited on Si substrate through the reactive evaporation process in carbon vapor and nitrogen plasma. The mechanical properties of the films deposited under various conditions have been surveyed and their nano-indentation characteristics have been especially investigated. The hardness of the films showed comparatively low values approximately 2–8 GPa. The hardness of films was lower than that of silicon substrate. However, the films have shown a large amount of elastic recovery on unloading, even if they did not have any resistance for penetration on loading.
In order to clarify the role of serotonin (5-HT) in the regulation of pituitary hormones, the effects of 5-HT injected into the third ventricle (3V) on prolactin (PRL) and growth hormone (GH) release ...were investigated in Holstein steers. A chronic cannula was implanted in 3V by stereotaxic surgery under general anesthesia. After sufficient recovery from surgery, 5-HT (0, 0.1, 1.0, 2.0 mg) was injected into via the cannula and blood samples were collected over 4 h. Plasma PRL and GH concentrations were determined by radioimmunoassay. PRL release was significantly stimulated by the injection of 5-HT. The increase in PRL was observed at 20 min after the injection at three doses and the highest dose (2.0 mg) was the most effective in stimulating PRL release. The injection of 5-HT into 3V, at all doses tested, did not alter GH release significantly. Our results suggest that 5-HT is involved in the regulation of PRL release partly through the hypothalamus in cattle.
The effects of melatonin (MEL) injection into the third ventricle (3V) on growth hormone (GH) secretion were investigated in conscious Holstein steers. A stainless steel cannula was stereotaxically ...implanted in the 3V based on the ventriculogram. In Exp. 1, three doses of MEL (100, 300 or 600 microg) were injected into the 3V through the cannula and the GH concentration after the injection was determined. In Exp. 2, intracerebroventricular (icv) and intravenous (iv) injections of MEL (100 microg) and GH-releasing hormone (GHRH; 0.25 microg/kg body weight), respectively, were performed simultaneously to examine the effect of MEL on GHRH-induced GH release. The icv injection of MEL significantly stimulated GH release at 100 microg. The increase in GH concentrations by 100 microg of MEL was persistent. Intravenous injection of GHRH dramatically increased GH release. The injection of MEL did not alter GHRH-induced GH release. These results suggest that MEL stimulates GH secretion possibly through the hypothalamus in cattle.
The effects of sucrose supplementation on nitrogen kinetics and energy metabolism were examined in sheep fed lucerne hay cubes using a 15N isotope dilution method and balance and respiration trials ...in Tsukuba, Japan in 1988. Sheep were fed lucerne hay cubes (1183 g DM/day), with or without 204 g/day sucrose, at 2 h intervals from continuous feeders. Supplementation with sucrose decreased urinary N excretion (P < 0·01), resulting in an increase in N retention from – 1·1 to + 2·0 g N/day (P < 0·01). Supplementation with sucrose resulted in no change in faeces and methane energy, a decrease in urinary energy (P < 0·01) and an increase in heat production and energy balance (P < 0·01). Sucrose supplementation also resulted in lower rumen ammonia (P < 0·05) and plasma urea concentrations (P < 0·05) and reduced urinary urea excretion (P < 0·01). The fermentation of sucrose in the rumen resulted in a decrease in rumen pH (P < 0·01) and in the acetate: propionate ratio (P < 0·05). Sucrose supplementation increased the proportion of urea transferred to the rumen (P < 0·05), non-ammonia N (NAN) concentration in the rumen (P < 0·001) and NAN flow from the rumen to the lower digestive tract (P < 0·001). Urinary allantoin excretion rate increased with sucrose supplementation (P < 0·05). The plasma glucose concentration was unchanged but plasma insulin concentration was increased with sucrose supplementation (P < 0·05). The influence of energy-rich supplements, such as sucrose, on N kinetics and the mechanism of the increase in N retention with sucrose supplementation are discussed.
This paper describes high-resolution micro-fluxgate magnetic sensing elements using magnetic thin films and closely coupled excitation and pick-up coils based on a solenoid-shaped coil structure. In ...order to improve the sensitivity of the sensing element, the optimal coupling structure between excitation and pick-up coils, and the formation method of permalloy magnetic films are investigated. The closely coupled coil structure allows the magnetic core to be excited in an optimal condition with reduced excitation current. The addition of indium to the permalloy plating bath greatly reduces the degradation of the magnetic core due to the thermal treatment process. The sensitivity of the fabricated sensing element is measured to be 2700 VT
−1 at an excitation frequency of 3 MHz. The noise level, or resolution in d.c. to 10 Hz bandwidth is measured to be about 40 nT
p−p.
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