Search

BackgroundConstipation and L-dopa-induced gastric dysmotility are common gastrointestinal (GI) symptoms in Parkinson's disease (PD). We investigated the novel ghrelin agonist, HM01 influence on GI motor dysfunctions in 6-hydroxydopamine (6-OHDA) rats.MethodsHM01 pharmacological profiles were determined in vitro and in vivo in rats. We assessed changes in fecal output and water content, and gastric emptying (GE) in 6-OHDA rats treated with orogastric (og) HM01 and L-dopa/carbidopa (LD/CD, 20/2 mg/kg). Fos immunoreactivity (ir) cells in specific brain and lumbosacral spinal cord were quantified.Key resultsHM01 displayed a high binding affinity to ghrelin receptor (Ki: 1.42 ± 0.36 nM), 4.3 ± 1.0 h half-life and high brain/plasma ratio. 6-OHDA rats had reduced daily fecal output (22%) and water intake (23%) compared to controls. HM01 (3 and 10 mg/kg) similarly reversed the decreased 4-h fecal weight and water content in 6-OHDA rats. Basal GE was not modified in 6-OHDA rats, however, LD/CD (once or daily for 8 days) delayed GE in 6-OHDA and control rats that was prevented by HM01 (3 mg/kg acute or daily before LD/CD). HM01 increased Fos-ir cell number in the area postrema, arcuate nucleus, nucleus tractus solitarius, and lumbosacral intermediolateral column of 6-OHDA rats where 6-OHDA had a lowering effect compared to controls.Conclusions & inferences6-OHDA rats display constipation- and adipsia-like features of PD and L-dopa-inhibited GE. The new orally active ghrelin agonist, HM01 crosses the blood-brain barrier and alleviates these alterations suggesting a potential benefit for PD with GI disorders.

The authors have previously developed and proposed methods to estimate the in situ rock strength and moth wear while drilling with roller-cone bits [Karasawa et al., 2002, ASME J. Energy Resour. Technol. 124, pp. 125-132 (Pt. 1) 133-140 (Pt. 2)]. The purpose of this paper is to provide a follow-up to these two reports and to propose, for both previous methods, alternate techniques that can be more readily implemented in the field than those originally presented. The data presented in Part 1 of the previously mentioned work [I] were reanalyzed in order to find a new and simple parameter that can be used to estimate rock strength. This parameter uses only one set of data that consists of bit weight, torque, penetration rate, rotary speed, and bit diameter. It was also demonstrated that the effect of tooth wear on this new parameter is small. In addition, more practical methods, which employ two parameters, are derived and proposed to evaluate the tooth wear of rollercone bits.

New methods to estimate both the rock strength and tooth wear while drilling with roller-bits were developed and proposed in Part 1. These methods were derived from the results of drilling tests using milled-tooth type three-cone bits with different amounts of tooth wear. In this report, these methods were extended and applied to insert type three-cone bits. The validity of the test and data analyses techniques of Part 1 were confirmed for insert bits. The methods to estimate the tooth wear proposed in Part 1 were based on the drillability strength of rock. A new approach to determine the tooth wear is presented. This new approach could be more readily applied to evaluating tooth wear when compared to the previous methods based on the drillability strength of rock. [DOI: 10.1115/1.1482406]

This paper proposes new methods to estimate both the rock strength and tooth wear while drilling with roller-bits. Laboratory drilling tests were conducted to obtain the penetration rate, bit weight and torque using milled-tooth bits with different tooth wear (T0, T4, T7). Drilling media used for the tests were soft to medium-hard rocks whose uniaxial compressive strength ranged from 14 to 118 MPa. Based on the test results, a parameter, which presents the rock strength independent of the tooth wear, was first investigated. The investigation revealed that a parameter related to the axial energy and the rotary energy required to drill rock is effective to estimate the rock strength independent of the tooth wear. Second, methods to estimate the tooth wear were studied based on the same parameter that represents the rock strength. From the results of this study, methods to measure the tooth wear are proposed. [DOI: 10.1115/1.1482405]

In order to develop polycrystalline diamond compact (PDC) bits of about 8-1/2 in. in diameter which are able to drill geothermal wells, we have conducted the investigation with respect to the structure of a PDC cutter and rake angles, etc., by means of fundamental laboratory and field tests. New PDC core bits of 8-15/32 in. diameter were designed and manufactured based on the results of these tests. Then, field tests using them were carried out in geothermal wells at Hijiori in Yamagata prefecture, Hot Dry Rock project site in Japan, on September 1989 and October 1990. It became clear that the new PDC core bit can be sufficiently applied to the drilling of heterogeneous hot-hard rock formations from the tests.

Rock cutting, drilling and durability tests were conducted in order to obtain data to design polycrystalline diamond compact (PDC) bits for geothermal well drilling. Both conventional and new PDC bits with different rake angles were tested. The rock cutting tests revealed that cutting forces were minimized at - 10 deg rake angle independent of rock type. In drilling and durability tests, a bit with backrake and siderake angles of - 10 or - 15 deg showed better performance concerning the penetration rate and the cutter strength. The new PDC bit exhibited better performance as compared to the conventional one, especially in hard rock drilling. Furthermore, a new PDC core bit (98.4 mm o. d., 66 mm i. d.) with eight cutters could be successfully applied to granite drilling equally as well as a bit with twelve cutters.

A new method for the synthesis of tartary buckwheat protein (TBP) and its effect on the cholesterol metabolism in rats and mice fed cholesterol-enriched diet are studied. The analysis reveals that TBP can be used as a potential source of functional food ingredients.