32 research outputs found
Relation of gallbladder function and Helicobacter pylori infection to gastric mucosa inflammation in patients with symptomatic cholecystolithiasis
Background. Inflammatory alterations of the gastric mucosa are commonly caused by Helicobacter pylori (Hp) infection in patients with symptomatic gallstone disease. However, the additional pathogenetic role of an impaired gallbladder function leading to an increased alkaline duodenogastric reflux is controversially discussed. Aim:To investigate the relation of gallbladder function and Hp infection to gastric mucosa inflammation in patients with symptomatic gallstones prior to cholecystectomy. Patients: Seventy-three patients with symptomatic gallstones were studied by endoscopy and Hp testing. Methods: Gastritis classification was performed according to the updated Sydney System and gallbladder function was determined by total lipid concentration of gallbladder bile collected during mainly laparoscopic cholecystectomy. Results: Fifteen patients revealed no, 39 patients mild, and 19 moderate to marked gastritis. No significant differences for bile salts, phospholipids, cholesterol, or total lipids in gallbladder bile were found between these three groups of patients. However, while only 1 out of 54 (< 2%) patients with mild or no gastritis was found histologically positive for Hp, this infection could be detected in 14 (74%) out of 19 patients with moderate to marked gastritis. Conclusion: Moderate to marked gastric mucosa inflammation in gallstone patients is mainly caused by Hp infection, whereas gallbladder function is not related to the degree of gastritis. Thus, an increased alkaline duodenogastric reflux in gallstone patients seems to be of limited pathophysiological relevance. Copyright (c) 2006 S. Karger AG, Basel
Comparison of muscle activity and tissue oxygenation during strength training protocols that differ by their organisation, rest interval between sets, and volume
Purpose: The acute effects of a single training session on muscle activity and oxygenation were compared between a new strength training method (3/7 protocol) and a more classical method (4Ā ĆĀ 6 and 8Ā ĆĀ 6 protocols). Method: All protocols consisted of lifting and lowering a load (70Ā % 1RM) with the elbow-flexor muscles. The 3/7 protocol involved 5 sets of increasing number of repetitions during successive sets (from 3 to 7 repetitions), and brief rest interval between sets (15Ā s). The other two protocols consisted of either 4 or 8 sets of 6 repetitions with a rest interval between sets of 2.5Ā min. Surface electromyogram (EMG) of biceps brachii, brachioradialis, and triceps brachii, and tissue oxygenation index (TOI) of the two elbow flexors were recorded. Result: For all muscles, EMG increased similarly (50ā60Ā %) during each set in the 4Ā ĆĀ 6 and 8Ā ĆĀ 6 protocols but gradually during the successive sets in the 3/7 protocol. At protocol completion, EMG reached greater value (pĀ <Ā 0.003) in the 3/7 protocol. TOI decreased during each set in all protocols but contrary to 4Ā ĆĀ 6 and 8Ā ĆĀ 6 protocols, it did not return to resting values between sets in the 3/7 protocol. The deficit in TOI per repetition was greater (pĀ <Ā 0.001) in the 3/7 (ā142.5Ā Ā±Ā 48.8Ā %) than 4Ā ĆĀ 6 (ā113.1Ā Ā±Ā 48.8Ā %) and 8Ā ĆĀ 6 (ā105.9Ā Ā±Ā 59.2Ā %) protocols for biceps brachii but not brachioradialis. Conclusion: The results indicate that brief rest interval between sets and incremental number of repetitions in successive sets induced greater muscle activity and metabolic changes compared with method of constant repetitions per set and longer rest interval.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Raman and SEM analysis of a biocolonised hot spring travertine terrace in Svalbard, Norway
A profile across 8 layers from a fossil travertine terrace from a low temperature geothermal spring located in Svalbard, Norway has been studied using both Raman spectroscopy and SEM (Scanning Electron Microscopy) techniques to identify minerals and organic life signals.
Calcite, anatase, quartz, haematite, magnetite and graphite as well as scytonemin, three different carotenoids, chlorophyll and a chlorophyll-like compound were identified as geo- and biosignatures respectively, using 785 and/or 514 nm Raman laser excitation wavelengths. No morphological biosignatures representing remnant microbial signals were detected by high-resolution imaging, although spectral analyses indicated the presence of organics. In contrast, in all layers, Raman spectra identified a series of different organic pigments indicating little to no degradation or change of the organic signatures and thus indicating the preservation of fossil biomarker compounds throughout the life time of the springs despite the lack of remnant morphological indicators.
With a view towards planetary exploration we discuss the implications of the differences in Raman band intensities observed when spectra were collected with the different laser excitations. We show that these differences, as well as the different detection capability of the 785 and 514 nm laser, could lead to ambiguous compound identification. We show that the identification of bio and geosignatures, as well as fossil organic pigments, using Raman spectroscopy is possible. These results are relevant since both lasers have been considered for miniaturized Raman spectrometers for planetary exploration
Physical Properties of Icy Materials
There is evidence that water-ice exists on a number of bodies in the solar system. As ice deposits may contain biomarkers that indicate the presence of life, or can be used as a consumable resource for future missions, confirming these observations with in-situ measurements is of great interest. Missions aiming to do this must consider how the presence of water-ice in regolith affects both the regolithās properties and the performance of the instruments that interact with it. The properties of icy lunar and Martian regolith simulants in preparation for currently planned missions are examined in this chapter. These results can be used in future instrumentation testing and missions designed to explore other icy bodies in the solar system. The testing of icy lunar regolith simulants is summarised, before focusing on experiments demonstrating the change in properties of frozen NU-LHT-2M, a simulant of the highlands regolith found at the lunar poles, as water is added. Further tests showed a critical point of 5 Ā± 1% water mass content where the penetration resistance significantly increases. The addition of water to Martian regolith simulants was also examined, with the presence of salts resulting in the formation of cemented crusts under simulated Martian conditions. Additional tests with the ExoMars PSDDS demonstrated how increased internal cohesion caused by the water resulted in the failure of the instrument