Early effects of oral administration of omeprazole and roxatidine on intragastric pH

Objective

The ideal medication for the treatment of acid-related diseases, e.g., peptic ulcers, stress-related gastric bleeding, functional dyspepsia, and gastroesophageal reflux disease, should have a rapid onset of action to promote hemostasis and relieve the symptoms. The aim of our study was to investigate the inhibitory effects on gastric acid secretion of a single oral administration of a proton pump inhibitor, omeprazole 20 mg, and an H₂-receptor antagonist, roxatidine 75 mg.

Methods

Ten Helicobacter pylori-negative male subjects participated in this randomized, two-way crossover study. Intragastric pH was monitored continuously for 6 h after single oral administration of omeprazole 20 mg and roxatidine 75 mg. Each administration was separated by a 7-d washout period.

Results

During the 6-h study period, the average pH after administration of roxatidine was higher than that after administration of omeprazole (median: 4.45 vs. 2.65; P=0.0367). Also during the 6-h study period, a longer duration of maintenance at pH above 2, 5, and 6 was observed after administration of roxatidine 75 mg than after administration of omeprazole 20 mg (median: 90.6% vs. 55.2%, P=0.0284; 43.7% vs. 10.6%, P=0.0125; 40.3% vs. 3.3%, P=0.0125; respectively).

Conclusions

In Helicobacter pylori-negative healthy male subjects, oral administration of roxatidine 75 mg increased the intragastric pH more rapidly than that of omeprazole 20 mg.     

The effects of different initial restrictive pressures used to reduce blood flow and thigh composition on tissue oxygenation of the quadriceps

Blood flow restriction training technique can be affected by several factors resulting in changes in responses to training; therefore it is necessary to investigate and reveal detailed information about this novel training technique. Participants had their thigh size, thickness of subcutaneous fat, and regional bone free muscle mass measured prior to testing. A Near-Infrared Spectrometer was used to measure tissue oxygenation and a cardiovascular profiling system was utilised to measure stroke volume and heart rate. Initial restrictive pressure of 30, 50, and 70 mmHg were set in random order on three separate days, and then six target pressures were sequentially applied. Tissue oxygenation decreased significantly as both initial restrictive pressure and target pressures increased, but the magnitude of decreases was stronger with higher initial restrictive pressure. There were significant negative correlations between tissue oxygenation and leg lean body mass, total lean body mass, and thigh circumference when initial restrictive pressure was set at 30 mmHg. The findings indicated that changes in initial restrictive pressure affected the amount of venous return verified by the decreases in tissue oxygenation and stroke volume. In addition, thigh composition and size had a significant impact on the effects of initial restrictive pressure.     

Intergroup contact in context: The mediating role of social norms and group-based perceptions on the contact–prejudice link

The prejudice-reducing effects of intergroup contact have been well documented. However few studies have investigated the importance of the broader context within which contact occurs. The current study examined the predictors of social distance from Muslims in a large sample of Australian secondary school children (N = 980). Intergroup contact was an important predictor of reduced social distance even after demographics and perceptions of parents, school, media and broader intergroup dynamics were taken into account. However, in part the contact–social distance relationship was mediated by perceived parental support for intergroup relations and perceived fairness of media representation. Student's perceptions of broader group dynamics relating to collective threat and differentiation between groups impeded the relationship. The findings attest to the importance of the broader context within which contact occurs. Having contact with outgroup members leads to reduced social distance to the outgroup, however perceived norms and outgroup perceptions play a pivotal role in explaining this relationship.     

Effect of a combination of astaxanthin supplementation,heat stress,and intermittent reloading on satellite cells during disuse muscle atrophy

We examined the effect of a combination of astaxanthin (AX) supplementation, repeated heat stress, and intermittent reloading (IR) on satellite cells in unloaded rat soleus muscles. Forty-nine male Wistar rats (8-week-old) were divided into control, hind-limb unweighting (HU), IR during HU, IR with AX supplementation, IR with repeated heat stress (41.0–41.5 °C for 30 min), and IR with AX supplementation and repeated heat stress groups. After the experimental period, the antigravitational soleus muscle was analyzed using an immunohistochemical technique. Our results revealed that the combination of dietary AX supplementation and heat stress resulted in protection against disuse muscle atrophy in the soleus muscle. This protective effect may be partially due to a higher satellite cell number in the atrophied soleus muscle in the IR/AX/heat stress group compared with the numbers found in the other groups. We concluded that the combination treatment with dietary AX supplementation and repeated heat stress attenuates soleus muscle atrophy, in part by increasing the number of satellite cells.     

Surface-mounted bender elements for measuring horizontal shear wave velocity of soils

The bender element testing features its in-plane directivity, which allows using bender elements to measure the shear wave velocities in a wider range of in-plane configurations besides the standard tip-to-tip alignment. This paper proposed a novel bender element testing technique for measuring the horizontal shear wave velocity of soils, where the bender elements are surface- mounted and the axes of the source and receiver elements are parallel to each other. The preliminary tests performed on model ground of silica sand showed that, by properly determining the travel distance and time of the shear waves, the surface-mounted bender elements can perform as accurately as the conventional ＂tip-to-tip＂ configuration. Potentially, the present system provides a promising nondestructive tool for characterizing geomaterials and site conditions both in laboratory and in the fields.     

Association between COMT Val158Met polymorphism and competition results of competitive swimmers

Recent studies have shown the contribution of genetic determinants to athletes’ physical ability. However, despite the fact that cognitive abilities like self-control and stress-tolerance influence athletes’ competitive performance, few studies to date have investigated the association between genetic polymorphism, which is linked to cognitive ability and athletic performance. The present study investigated the link between single-nucleotide polymorphisms (SNPs), which are known to exert influences on dopaminergic neural function and competitive performance of swimmers. The results have revealed superior competitive performance in competitive swimmers with Met allele of catechol-O-methyltransferase Val158Met polymorphism than those with Val/Val genotype. The investigated SNPs of DRD2 and DRD3 were not associated with swimmer’s competitive performance. This finding indicates that genetic polymorphism linked to cognitive ability influences the athletes’ performance.     

Some thoughts on implementing U.S. physics doctoral education in Japanese universities

Recent policy debates surrounding Japan??s graduate education raise a serious skepticism in the validity of its ??research-based?? or ??learning-by-doing?? training approach that these institutions have uniquely established. Proponents of reform suggest drastic restructuring of the graduate programs by replacing the experience-based mentoring aspect with more systematic education that blends an array of coursework and examinations. However, whether such a coursework-based model of graduate training will successfully function without sacrificing the traditional virtue of Japanese practices is an unsubstantiated matter. Japanese graduate schools have produced scientists who have made immense contributions to the advancement in our scientific knowledge. Policy makers and academia in Japan should humbly acknowledge this fact and prudently determine what aspects of their educational content should be reformed and what should be retained. In order to do this, the merits and demerits of alternative models must be clearly understood. The objective of this study is to affirm both the strengths and weaknesses of the traditional approach that Japanese universities need to consider preserving and eliminating, in order to capitalize on their institutional heritage while also building in the educational caliber of the rigorous US graduate training model in the reforming process.