342 research outputs found

    Fecal continence for solid and liquid stool:The function of the anal-external sphincter continence reflex and the puborectal continence reflex

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    BACKGROUND: The anal-external sphincter continence reflex and the puborectal continence reflex control fecal continence by involuntary contractions of the external anal sphincter and puborectal muscle. To date it is unknown what the effect of liquid stool is on these reflexes. OBJECTIVE: The purpose of this study was to analyze the consequence of liquid stool on the presence and function of these fecal continence reflexes. DESIGN: This was a prospective, observational study. SETTING: The study was conducted at the Anorectal Physiology Laboratory, University Medical Center Groningen. PATIENTS: Forty-two healthy subjects were included. MAIN OUTCOME MEASURES: Pressure changes at the level of the external anal sphincter and the puborectal muscle during the anorectal pressure test used to measure voluntary contractions, the balloon retention test used to measure involuntary contractions mimicking solid stool, and the rectal infusion test used to investigate the effect of only water mimicking liquid stool were measured. RESULTS: During the test mimicking solid stool, the pressure at the level of the external anal sphincter increased from the start to the end (132 ± 54 vs 198 ± 69 mm Hg; p < 0.001). The pressure at the level of the puborectal muscle increased simultaneously (30 ± 9 vs 176 ± 52 mm Hg; p < 0.001). After injecting water into the rectum, mimicking liquid stool, we observed immediate activation of the anal-external sphincter continence reflex (87 ± 32 vs 145 ± 36 mm Hg; p < 0.001); this was after a median 30 seconds, whereas no activation of the puborectal continence reflex appeared (26 ± 9 vs 26 ± 7 mm Hg; p = 0.655). LIMITATIONS: We only performed anorectal function tests mimicking 2 types of stool consistencies, namely water and solid. CONCLUSIONS: The anal-external sphincter continence reflex controls fecal continence of both solid and liquid stool. Contrarily, the puborectal continence reflex contributes to solid stool continence only. See Video Abstract at http://links.lww.com/DCR/B286

    Functional outcomes of surgery for colon cancer:A systematic review and meta-analysis

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    Introduction: As survival rates of colon cancer increase, knowledge about functional outcomes is becoming ever more important. The primary aim of this systematic review and meta-analysis was to quantify functional outcomes after surgery for colon cancer. Secondly, we aimed to determine the effect of time to follow-up and type of colectomy on postoperative functional outcomes. Materials and methods: A systematic literature search was performed to identify studies reporting bowel function following surgery for colon cancer. Outcome parameters were bowel function scores and/or prevalence of bowel symptoms. Additionally, the effect of time to follow-up and type of resection was analyzed. Results: In total 26 studies were included, describing bowel function between 3 to 178 months following right hemicolectomy (n = 4207), left hemicolectomy/sigmoid colon resection (n = 4211), and subtotal/total colectomy (n = 161). In 16 studies (61.5%) a bowel function score was used. Pooled prevalence for liquid and solid stool incontinence was 24.1% and 6.9%, respectively. The most prevalent constipation-associated symptoms were incomplete evacuation and obstructive, difficult emptying (33.3% and 31.4%, respectively). Major Low Anterior Resection Syndrome was present in 21.1%. No differences between time to follow-up or type of colectomy were found. Conclusion: Bowel function problems following surgery for colon cancer are common, show no improvement over time and do not depend on the type of colectomy. Apart from fecal incontinence, constipation-associated symptoms are also highly prevalent. Therefore, more attention should be paid to all possible aspects of bowel dysfunction following surgery for colon cancer and targeted treatment should commence promptly

    Review: Markers and proxies to monitor ruminal function and feed efficiency in young ruminants

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    Developing the rumen’s capacity to utilise recalcitrant and low-value feed resources is important for ruminant production systems. Early-life nutrition and management practices have been shown to influence development of the rumen in young animals with long-term consequences on their performance. Therefore, there has been increasing interest to understand ruminal development and function in young ruminants to improve feed efficiency, health, welfare, and performance of both young and adult ruminants. However, due to the small size, rapid morphological changes and low initial microbial populations of the rumen, it is difficult to study ruminal function in young ruminants without major invasive approaches or slaughter studies. In this review, we discuss the usefulness of a range of proxies and markers to monitor ruminal function and nitrogen use efficiency (a major part of feed efficiency) in young ruminants. Breath sulphide and methane emissions showed the greatest potential as simple markers of a developing microbiota in young ruminants. However, there is only limited evidence for robust indicators of feed efficiency at this stage. The use of nitrogen isotopic discrimination based on plasma samples appeared to be the most promising proxy for feed efficiency in young ruminants. More research is needed to explore and refine potential proxies and markers to indicate ruminal function and feed efficiency in young ruminants, particularly for neonatal ruminants

    Fast protein liquid chromatography : gel filtration of actin and its quantitative analysis by 3 Methyl-L-Histidine

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    This study describes the experiences with the FPLC-technique for the separation of actin from a mixture composed of some single muscle proteins like myosin, [alpha] - actinin, tropomyosin and troponin, and the quantitative analysis of actin

    Spin oscillations in transient diffusion of a spin pulse in n-type semiconductor quantum wells

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    By studying the time and spatial evolution of a pulse of the spin polarization in nn-type semiconductor quantum wells, we highlight the importance of the off-diagonal spin coherence in spin diffusion and transport. Spin oscillations and spin polarization reverse along the the direction of spin diffusion in the absence of the applied magnetic field are predicted from our investigation.Comment: 5 pages, 4 figures, accepted for publication in PR

    Evidence for a Low-Spin to Intermediate-Spin State Transition in LaCoO3

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    We present measurements of the magnetic susceptibility and of the thermal expansion of a LaCoO3_3 single crystal. Both quantities show a strongly anomalous temperature dependence. Our data are consistently described in terms of a spin-state transition of the Co3+^{3+} ions with increasing temperature from a low-spin ground state to an intermediate-spin state without (100K - 500K) and with (>500K) orbital degeneracy. We attribute the lack of orbital degeneracy up to 500K to (probably local) Jahn-Teller distortions of the CoO6_6 octahedra. A strong reduction or disappearance of the Jahn-Teller distortions seems to arise from the insulator-to-metal transition around 500 K.Comment: an error in the scaling factor of Eq.(4) and consequently 2 values of table I have been corrected. The conclusions of the paper remain unchanged. See also: C. Zobel et al. Phys. Rev. B 71, 019902 (2005) and J. Baier et al. Phys. Rev. B 71, 014443 (2005

    Manifold-Topology from K-Causal Order

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    To a significant extent, the metrical and topological properties of spacetime can be described purely order-theoretically. The K+K^+ relation has proven to be useful for this purpose, and one could wonder whether it could serve as the primary causal order from which everything else would follow. In that direction, we prove, by defining a suitable order-theoretic boundary of K+(p)K^+(p), that in a KK-causal spacetime, the manifold-topology can be recovered from K+K^+. We also state a conjecture on how the chronological relation I+I^+ could be defined directly in terms of K+K^+.Comment: v2: 9 pages, 2 figures. Minor change

    Forced oscillations in a hydrodynamical accretion disk and QPOs

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    This is the second of a series of papers aimed to look for an explanation on the generation of high frequency quasi-periodic oscillations (QPOs) in accretion disks around neutron star, black hole, and white dwarf binaries. The model is inspired by the general idea of a resonance mechanism in the accretion disk oscillations as was already pointed out by Abramowicz & Klu{\'z}niak (\cite{Abramowicz2001}). In a first paper (P\'etri \cite{Petri2005a}, paper I), we showed that a rotating misaligned magnetic field of a neutron star gives rise to some resonances close to the inner edge of the accretion disk. In this second paper, we suggest that this process does also exist for an asymmetry in the gravitational potential of the compact object. We prove that the same physics applies, at least in the linear stage of the response to the disturbance in the system. This kind of asymmetry is well suited for neutron stars or white dwarfs possessing an inhomogeneous interior allowing for a deviation from a perfectly spherically symmetric gravitational field. We show by a linear analysis that the disk initially in a cylindrically symmetric stationary state is subject to three kinds of resonances: a corotation resonance, a Lindblad resonance due to a driven force and a parametric sonance. The highest kHz QPOs are then interpreted as the orbital frequency of the disk at locations where the response to the resonances are maximal. It is also found that strong gravity is not required to excite the resonances.Comment: Accepte

    Interplay of superexchange and orbital degeneracy in Cr-doped LaMnO3

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    We report on structural, magnetic and Electron Spin Resonance (ESR) investigations in the manganite system LaMn_{1-x}Cr_{x}O_{3} (x<=0.5). Upon Cr-doping we observe a reduction of the Jahn-Teller distortion yielding less distorted orthorhombic structures. A transition from the Jahn-Teller distorted O' to the pseudocubic O phase occurs between 0.3<x<0.4. A clear connection between this transition and the doping dependence of the magnetic and ESR properties has been observed. The effective moments determined by ESR seem reduced with respect to the spin-only value of both Mn^{3+} and Cr^{3+} ions
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