Background
Reflux monitoring using combined multichannel intraluminal impedance (MII) and pH-metry increases the sensitivity for identifying gastroesophageal reflux episodes. The likelihood of a ...positive symptom index (SI) for patients with reflux disease (gastroesophageal reflux disease GERD or nonerosive reflux disease NERD) receiving proton pump inhibitor (PPI) treatment has been used to select candidates for antireflux surgery. Little is known about the advantages of MII-pH monitoring compared with pH monitoring alone for evaluating GERD/NERD patients off PPI treatment considered as candidates for antireflux surgery or for assessing changes in MII-pH-detected reflux episodes after antireflux surgery. This study aimed to determine the additional value of MII over pH-metry alone for patients off PPI treatment before and after antireflux surgery.
Methods
For this study 12 patients (4 women and 8 men; mean age, 45 years; range, 27–74 years) were evaluated using ambulatory MII-pH monitoring before and 3 months after mesh-augmented hiatoplasty. Reflux events were identified by MII-pH (A) and pH-metry (B) as patients recorded symptoms on a data logger. For each symptom, a symptom index was calculated for reflux events identified by MII-pH and by pH-monitoring alone.
Results
Preoperatively, MII-pH monitoring identified 71.9 ± 8.4 reflux episodes, whereas pH monitoring identified only 51.0 ± 7.8 (
p
< 0.05). Postoperatively, MII-pH monitoring identified 35.5 ± 6.6 reflux episodes, whereas pH monitoring identified only 19.6 ± 4.7 (
p
< 0.05). The pre- and postoperative symptom index for MII-pH monitoring was higher than pH monitoring (preoperative 91.7% vs 25%,
p
= 0.006; postoperative 50% vs 16.7%,
p
= 0.012).
Conclusion
Combined MII-pH-metry improves the pre- and postoperative assessment of GERD patients off PPI and results in a higher symptom-reflux association.
The Drosophila Standard Brain Rein, Karlheinz; Zöckler, Malte; Mader, Michael T. ...
CB/Current biology,
02/2002, Volume:
12, Issue:
3
Journal Article
Peer reviewed
Open access
Organisms and organs come in sizes and shapes. With size, science has no problems, but how to quantify shape? How similar are two birds or two brains? This problem is particularly pressing in cases ...like brains where structure reflects function. The problem is not new, but satisfying solutions have yet to be worked out. For brain anatomy, no general methodology for a statistically secured quantitative description is available. Using the small brain of the fly Drosophila melanogaster, we have explored a new approach combining immunohistochemistry, high-resolution 3D confocal microscopy, and advanced graphics computing. For a genetic model organism such as Drosophila, a quantitative assessment of brain structure is particularly rewarding, since it allows for the identification of genetic variants with subtle brain structure phenotypes and, even more importantly, the organization of the wealth of gene expression patterns in the brain into a genetic atlas linking molecular and organismic gene function. We now provide a representative standard for the brain of D. melanogaster wild-type with means and variances for several aspects of its shape. Its application to volumetry, mutants, and gene expression patterns is demonstrated.
Background Diffuse esophageal spasm (DES) is characterized on manometry by a combination of simultaneous contractions and normal swallows. The aim of this study was to examine the manometric ...characteristics of simultaneous and ‘normal’ swallows in patients with DES patients compared with normal controls.
Methods Manometric studies from 69 patients with DES and 20 controls were analysed to determine the proportion of normal, hypertensive, ineffective and simultaneous contractions, and the velocity of propagation along the esophagus, the duration and amplitude of contraction and the relaxation characteristics (nadir and duration) of the lower esophageal sphincter.
Key Results The propagation velocity was the only significant difference between normal swallows and simultaneous contractions in DES patients (middle third: 49.2 VS 101.2 mm s−1, P ≤ 0.001 lower third: 44.1 VS 88.7 mm s−1, P ≤ 0.001). ‘Normal’ swallows in patients with DES had a greater velocity of propagation than those in age‐matched control subjects (middle third: 49.2 VS 37.0 mm s−1, P = 0.02, lower third: 44.1 VS 23.3 mm s−1, P ≤ 0.001).
Conclusions & Inferences As expected, simultaneous contractions of DES patients differ from ‘normal’ swallows in DES patients mainly regarding the velocity of propagation of contraction but are similar in amplitude, however ‘normal’ swallows of DES patients are also more rapidly propagated along the esophagus than normal swallows of a control group suggesting that all swallows in DES are affected to some degree by the same process.
Problemstellung:
Die Abdomensonographie ist bei stationären gastroenterologischen Patienten eine unverzichtbare Methode für die Primär- und Verlaufsdiagnostik. Zeitliche und räumlich-apparative ...Ressourcenknappheit führen häufig zu verzögerter Diagnostik mit verlängerter Hospitalisationsdauer. Ziel dieser prospektiven Studie war die Evaluation der „bedside sonography“ im Vergleich zur konventionellen Sonographie bezüglich Zeitaufwand für Transport und Vorbereitung des Patienten und Einfluss auf die Patientenprozesse auf einer gastroenterologischen Schwerpunktstation.
Methoden:
1. Bei konsekutiv eingeschlossenen Pat. wurde der Zeitaufwand des Pflegepersonals (Transport, Vor- und Nachbereitung des Pat.) für eine konventionelle Sonographie (Gruppe A) und für die Installation des Gerätes für eine „bedside sonography“ (Gruppe B) erfasst. 2. Die durch einen Kaderarzt gestellten Diagnosen der Gruppe B wurden erfasst und in drei sonographische Schwierigkeitsstufen (1=Basiskenntnisse, 2=Solide Grundlagenkenntnisse, 3=Fortgeschritten) klassifiziert. 3. Die Relevanz der Befunde mit Einfluss auf das Patientenmanagement wurde in 3 Kategorien erfasst (Handlungsbedarf: 1=kein, 2=innert 24–48h, 3=<12h). Alle Patienten wurden mit einem Gerät Hitachi EUB 6500 untersucht.
Ergebnisse:
Von Mitte Mai bis August 2004 wurden 32 Pat. (14 F, 18 M, mittleres Alter 66 von 28 bis 91) konventionell sonographisch (Gruppe A) und 26 Pat. (11 F, 15 M, mittleres Alter 57 von 17 bis 89) mittels „bedside sonography“ (Gruppe B) untersucht. Der durchschnittliche Zeitaufwand für den Transport und die Patientenvorbereitung in Gruppe A (Bett n=11, Rollstuhl n=7, zu Fuss n=14), bzw. die Geräteinstallation in Gruppe B betrugen 12.25 (min. 4, max. 23.73) Min., bzw. 5.08 (min. 3.58 max. 6.16) Min. In 11% der Gruppe A waren 2 Pflegende für den Transport notwendig. In 42% und 35% der Fälle waren fortgeschrittene oder solide sonographische Grundlagenkenntnisse, in 23% lediglich Basiskenntnisse erforderlich. In 31% resultierte eine hohe, in 54% eine mittlere und lediglich in 15% eine kleine Relevanz der Befunde mit entsprechendem Handlungsbedarf.
Schlussfolgerungen:
Die „bedside sonography“ spart zeitliche Ressourcen des Pflegepersonals ein. Die rasche sonographische Diagnostik während der Arztvisite optimiert die Patientenprozesse. Die Untersuchung durch die betreuenden Stationsärzte hat zudem den Vorteil der optimalen Information über die Problemstellung.
Multiferroics have attracted strong interest for potential applications where electric fields control magnetic order. The ultimate speed of control via magnetoelectric coupling, however, remains ...largely unexplored. Here, we report an experiment in which we drove spin dynamics in multiferroic TbMnO3 with an intense few-cycle terahertz (THz) light pulse tuned to resonance with an electromagnon, an electric-dipole active spin excitation. We observed the resulting spin motion using time-resolved resonant soft x-ray diffraction. Our results show that it is possible to directly manipulate atomic-scale magnetic structures with the electric field of light on a sub-picosecond time scale.
During ultrafast demagnetization of a magnetically ordered solid, angular momentum has to be transferred between the spins, electrons, and phonons in the system on femto- and picosecond timescales. ...Although the intrinsic spin-transfer mechanisms are intensely debated, additional extrinsic mechanisms arising due to nanoscale heterogeneity have only recently entered the discussion. Here we use femtosecond X-ray pulses from a free-electron laser to study thin film samples with magnetic domain patterns. We observe an infrared-pump-induced change of the spin structure within the domain walls on the sub-picosecond timescale. This domain-topography-dependent contribution connects the intrinsic demagnetization process in each domain with spin-transport processes across the domain walls, demonstrating the importance of spin-dependent electron transport between differently magnetized regions as an ultrafast demagnetization channel. This pathway exists independent from structural inhomogeneities such as chemical interfaces, and gives rise to an ultrafast spatially varying response to optical pump pulses.
•Linearly decreasing porosities at an increasing diameter of from 250 to 500 μm; pores located mostly between the contour and the hatch infill.•Increasing α-Ti texture at an increasing diameter of ...the microbeams due to the increasing size of large central crystal domains originated from a single or very few parent β-Ti grains.•Increasing Young’s modulus and UTS increases at an increasing diameter of the microbeams slightly due to the increasing texture towards the crystal orientation with a higher modulus, and the decreasing pore volume ratio and surface-to-volume ratio of the microbeams, respectively.•High yield strength/E ratio of Ti-6Al-4V structures manufactured by selected laser melting, attractive as elements for metallic mechanical metamaterials, in particular in this study the 375 μm diameter microbeams.
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The size effect of Ti-6Al-4V submillimeter structures manufactured by selective laser melting, which is critical for metallic mechanical metamaterials of unique mechanical properties, for example, negative Poisson's ratio and ultrahigh modulus, which show promise in biomedical, environmental, energy-related applications, has not been systematically investigated. Presented here are the quantification of the porosities by X-ray microtomography scans, texture analysis, and mechanical characterization of the additively manufactured Ti-6Al-4V microbeams. We found linearly decreasing porosities, increasing mechanical properties, and increasing texture in the microbeam with increasing diameter from 250 to 500 µm. The variation of microstructure in microbeams of different diameters and along the sample height, resulting from the printing parameters and the thermal conditions, leads to the discrepancy between the behavior observed in experiments and finite element simulation. Our results provide the structure-property-processing correlation to improve the manufacturing and prediction of the mechanical behavior of metallic mechanical metamaterials.
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