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81.
Kushaljit Singh Sodhi Vivek Virmani M. S. Sandhu N. Khandelwal 《The Indian journal of surgery》2015,77(2):104-110
Diagnosis of abdominal wall hernia is often a clinical problem, especially in occult or in obese patients. Multidetector CT is an accurate method of detecting various types of abdominal and diaphragmatic hernias. It clearly demonstrates the anatomical sites of hernial sac, its contents and possible complications. 相似文献
82.
Purpose:The 2-year outcomes of patients undergoing repair of triple labrum tears using an all-suture anchor device were assessed.Results:Overall total CS and FLEX-SF scores increased from 52.9 ± 20.4 to 84.3 ± 10.7 (P < 0.0001) and from 29.3 ± 4.7 to 42.0 ± 7.3 (P < 0.0001), respectively. When divided into two groups by whether or not glenohumeral arthrosis was present at the time of surgery (n = 9 each group), significant improvements in CS and FLEX-SF were obtained for both groups (P < 0.0015). There were no intraoperative complications. All patients, including contact athletes, returned to their preinjury level of sports activity and were satisfied. MRI evaluation revealed no instances of subchondral cyst formation or tunnel expansion. Anchor tracts appeared to heal with fibrous tissue, complete bony healing, or combined fibro-osseous healing.Conclusion:Our results are encouraging, demonstrating a consistent healing of the anchor tunnels through arthroscopic treatment of complex labrum lesions with a completely suture-based implant. It further demonstrates a meaningful improvement in patient outcomes, a predictable return to activity, and a high rate of patient satisfaction.
Level of Evidence:
Level IV case series. 相似文献83.
Chrystian Ochoa Shang Gao Samanvaya Srivastava Vivek Sharma 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(25)
Ultrathin foam films containing supramolecular structures like micelles in bulk and adsorbed surfactant at the liquid–air interface undergo drainage via stratification. At a fixed surfactant concentration, the stepwise decrease in the average film thickness of a stratifying micellar film yields a characteristic step size that also describes the quantized thickness difference between coexisting thick–thin flat regions. Even though many published studies claim that step size equals intermicellar distance obtained using scattering from bulk solutions, we found no reports of a direct comparison between the two length scales. It is well established that step size is inversely proportional to the cubic root of surfactant concentration but cannot be estimated by adding micelle size to Debye length, as the latter is inversely proportional to the square root of surfactant concentration. In this contribution, we contrast the step size obtained from analysis of nanoscopic thickness variations and transitions in stratifying foam films using Interferometry Digital Imaging Optical Microscopy (IDIOM) protocols, that we developed, with the intermicellar distance obtained using small-angle X-ray scattering. We find that stratification driven by the confinement-induced layering of micelles within the liquid–air interfaces of a foam film provides a sensitive probe of non-DLVO (Derjaguin–Landau–Verwey–Overbeek) supramolecular oscillatory structural forces and micellar interactions.Molecules in simple liquids and supramolecular structures in complex fluids can stratify or undergo confinement-induced layering induced by symmetry breaking at a solid–liquid or a fluid–fluid interface (1–8). In freestanding or foam films, the confinement-induced layering of supramolecular structures including micelles (9–17), lipid layers (18, 19), polyelectrolyte–surfactant complexes (20, 21), nanoparticles (9, 22), and liquid crystalline assemblies (23) can result in drainage via stratification. Due to thin film interference, foam films visualized under white light illumination display iridescent colors for thick films (h > 100 nm) (24–28), but ultrathin films (h < 100 nm) exhibit shades of gray that get progressively darker as the film gets thinner (9–21). In reflected light microscopy, micellar foam films exhibit coexisting thick−thin regions with distinct shades of gray. Interferometry-based measurement of the average film thickness over time decreases in a stepwise fashion yielding a step size, (9–17). Many published studies argue (9–12, 22, 29–34) that foam films containing charged micelles or latex particles stratify analogously due to the formation of “ordered colloidal crystals” (OCCs) and step size, , equals the intermicellar distance, d, in bulk solutions. However, a comparison of concentration-dependent obtained from the dynamic foam stratification studies (influenced by confinement effects) with measured using small-angle X-ray or neutron scattering (SAXS or SANS) or other direct measurements of static equilibrium structure, and related evidence for or against the formation of OCCs in micellar foam films, are lacking in the literature. Thus, the motivations of this contribution are threefold: 1) contrast the step size, , obtained via stratification studies with the intermicellar distance, , and micelle dimensions determined using SAXS; 2) examine the SAXS data for any evidence of OCCs; and 3) elucidate the influence of ionic micelles on foam film stability and topography, as well as on colloidal forces, in multicomponent complex fluids.Micelles, formed by self-assembly of soaps and detergents and ever present in typical household foams, facilitate cleaning and detergent action by solubilizing oils and oil-soluble dirt within their hydrophobic core (2, 34, 35). Micelles formed by biosurfactants like bile salt and rhamnolipids can be used for delivering nonpolar, bio-active polyunsaturated oils, flavonoids, vitamins, and hydrophobic drugs (36–38). Therefore, understanding the stability and lifetime of micellar foams is essential toward molecular engineering of formulations, controlling foams in industrial reactors, rivers, and lakes and developing bio-surfactants (36–38). Foam film drainage involves interfacial flows that are influenced both by bulk rheology and interfacial rheology as well as Laplace or capillary pressure, (set by surface tension, σ and curvature, C) (27, 28, 39–41). Additionally, thickness transitions and variations in ultrathin (h < 100 nm) freestanding as well as supported (containing one or two solid boundaries) films (41–43) depend on disjoining pressure, , defined as the free energy required to change unit thickness at constant temperature, T, pressure, P, surface area, A, and mole number, Ni (1, 34, 40–42). Intermolecular and surface forces determine the strength and range of disjoining pressure, , as well as of colloidal interaction forces, (1–3, 35, 40–42). Physical properties of surfactant solutions like surface tension and conductivity show distinct change around a critical micelle concentration (CMC), beyond which spheroidal micelles can form (2, 34, 35), and rod-like micelles, lamellar phases, etc., emerge at higher concentrations (44–46). In foam films formed with ionic surfactant at c < CMC, drainage below h < 30 nm often leads to the formation of relatively long-lived common black (CB) film attributed to counterbalancing of Pc by , the disjoining pressure due to DLVO (Derjaguin–Landau–Verwey–Overbeek) forces contributed by van der Waals and electrostatic double-layer interactions (1–3, 35, 39, 40). Even thinner Newton black (NB) films attest to the role of shorter-range, non-DLVO surface forces (14, 25–27, 40, 41). In contrast, in micellar foam films (c > CMC), a non-DLVO, oscillatory structural force, , counterbalances Pc at multiple flat thicknesses, manifested as distinct shades of gray in reflected light microscopy (9–17, 21, 40, 47–50).For micellar fluids containing charged micelles, the step size, , obtained using thickness–time plots from stratification experiments, and periodicity, , of directly measured using thin-film balance (47, 48) show that both periodicity and step size exceed micelle size, a, implying and . In 1971, Bruil and Lyklema (51) were the first to report that the concentration-dependent decrease in step size measured for sodium dodecyl sulfate (SDS) solutions followed a power law of the form and wrote that step size values “seem to be related to intermolecular distance in the (unmicellized) bulk solution.” In 1988, Nikolov et al. (9) reported that foam films containing latex particles stratified in a fashion similar to micellar foam films and argued that diffusion-driven, layer-by-layer removal of micelles or particles from an ordered colloidal crystal (OCC) structure drives stratification. In their OCC or “micelle-vacancy diffusion” mechanism, they proposed that the effective film viscosity increases with decrease in stratified film thickness (9, 10, 29–31, 33). Contrastingly, in the “hydrodynamic” mechanism, Bergeron and Radke (13, 47) described stratification using a thin-film equation, by incorporating and bulk solution viscosity. Nikolov et al. (9, 10, 29–31) suggested that the step size, , was equal to an effective diameter, , computed by adding the fixed length of SDS molecules, lSDS, to the Debye length, , that captures the range of screened electrostatic interactions. However, the step size and the Debye length display distinct power laws, and the measured step size exceeds the micelle size, a, as well as the computed effective diameter, deff, for ionic micellar systems, or typically and .Studies on charged nanoparticle dispersions find that the periodicity, , of the oscillatory structural force, , measured directly with surface force apparatus (SFA), or colloidal probe atomic force microscopy (CP-AFM), correlates well with the interparticle distance, d, obtained using scattering and simulations (4, 5, 52–55). Furthermore, the periodicity, , is primarily set by the particle number density, , and is relatively independent of added salt, charge at solid surfaces, and particle size, a (4, 5, 53–55). Assuming that analogy between in the nanoparticle studies and in stratified foam studies arises due to similar underlying physics, Danov et al. (32) and Anachkov et al. (11) argued that or step size equals the intermicellar distance, d, in bulk solutions and hypothesized that step size from stratification studies could be used for determining aggregation number as . However, Yilixiati et al. (17) showed that on salt addition, the measured values for micellar SDS solutions do not collapse onto a single curve even if plotted against micellar number density, , as micelle number and dimensions can change on the addition of salt (or surfactant) (2), whereas nanoparticle dimensions remain constant. Furthermore, solid boundaries that can impact SFA and AFM measurements are absent in stratifying foam films. However, the thickness of stratifying films is rather heterogeneous, and the average thickness changes in a stepwise fashion. Thus, the analogy between stratifying micelles in foam films and stratifying nanoparticle dispersions under confinement between solid surfaces requires further investigation. In particular, a comparison between multiple length-scales including micelle dimensions, Debye length, intermicellar distance, d and step-size, , and the consequences of thickness heterogeneities within foam films are warranted.In this study, we contrast the concentration-dependent changes in step-size measured in foam stratification studies with micellar dimensions and intermicellar distances in bulk solutions obtained using SAXS for aqueous solutions of SDS. For the range of concentrations (25 mM ≤ cSDS ≤ 250 mM) explored here, bulk rheology, interfacial tension, micelle shape and size, and interfacial charge (or potential) are nearly constant. Hence, the observed concentration-dependent changes in step-size and nanoscopic topography in stratifying films are dictated by the corresponding changes in intermicellar interactions and the resulting disjoining pressure, . We visualize and analyze nanoscopic thickness variations and transitions in stratifying foam films using IDIOM (Interferometry Digital Imaging Optical Microscopy) protocols (16) (Fig. 1A) that provide requisite spatiotemporal resolution (thickness ∼1 nm, in-plane < 1 μm, time < 1 ms). We analyze SAXS data to compute micelle dimensions, volume fraction, and microstructure (order) in bulk solutions and obtain the intermicellar distance from structure factor peak in SAXS data. Finally, we discuss the ramifications of the close comparison between step size from the foam film stratification studies and micellar dimensions and intermicellar distance determined using SAXS analysis on the intermicellar interactions and the mechanistic basis of stratification.Open in a separate windowFig. 1.Schematic of the setup used for examining stratification using IDIOM protocols and illustrative examples of stepwise thinning. (A) The Scheludko-like cell contains a plane-parallel film and surrounding meniscus that emulates a single foam film and its Plateau border. The cell is placed in a closed container and stratification is visualized using reflected light microscopy. A finite volume of fluid is inserted into the cell using the side-arm connected to a syringe. No liquid is added or withdrawn during the stratification experiment, and drainage from the film into the meniscus occurs freely and spontaneously. (B) Spatiotemporal variation in interference intensity I(x, y, t; λ) is used for computing thickness transitions and variations in stratifying films. (C) Average film thickness plotted as a function of time shows stepwise thinning for foam films made with aqueous SDS solutions. The spikes and dips in thickness plots appear when mesas or domains emerge in the region selected for computing average thickness. The data are shifted horizontally for clarity. 相似文献
84.
Venkata?Anudeep Kolar?Vishwanath?VinodEmail author Nandini?Pandit Vivek?Kumar?Sharma Halanaik?Dhanapathi Tarun?Kumar?Dutta Akkilagunta?Sujiv 《Indian journal of gastroenterology》2016,35(5):385-392
Background and Aims
Upper gastrointestinal symptoms are more prevalent among type 2 diabetes mellitus (T2DM) patients. The prevalence of delayed gastric emptying (GE) and factors predictive of it have not been studied in Indian T2DM patients and the present study aimed to study the same.Methods
This hospital-based cross-sectional study involved adult (age between 18 and 65 years) outpatients with T2DM of ≥5-year duration. Measurements of GE of a labelled standardized solid rice idli meal by gastric emptying scintigraphy (GES), symptoms of delayed GE (by standardized questionnaire) and autonomic function by cardiovascular autonomic function tests (AFTs) were carried out. Thirty healthy subjects served as controls for GES and AFTs.Results
One hundred and forty T2DM patients (age range: 32–65 years) were studied. Delayed GE was documented in ≈29 % (40/140) and rapid GE in 2 % (3/140) of T2DM patients. Univariate analysis showed significant positive association between delayed GE and duration of DM, body mass index (BMI), HbA1c, retinopathy, peripheral neuropathy, autonomic dysfunction and coronary artery disease (p < 0.05 for all). However, there was no significant correlation of age, sex, symptoms suggestive of gastroparesis and nephropathy with delayed GE. Hypoglycemic episodes were significantly more frequent in those with delayed GE (p < 0.05). Multiple logistic regression analysis revealed only BMI and HbA1c to be significant independent predictors of delayed GE.Conclusion
Presence and severity of symptoms of gastroparesis did not predict delayed GE. Delayed GE, irrespective of symptoms, was associated with microvascular and macrovascular diabetic complications and increased risk of hypoglycemic episodes. HbA1c and BMI were independent predictors of delayed GE.85.
86.
87.
Pulimood AB Ramakrishna BS Rita AB Srinivasan P Mohan V Gupta S Perakath B Kang G Chandy G Balasubramanian KA 《Journal of gastroenterology and hepatology》2008,23(5):752-758
Background and Aim: Macrophages and dendritic cells are closely related mononuclear phagocytic cells. Little is known about their in vivo role in acute intestinal bacterial infections in humans. We undertook to evaluate these cells in rectal mucosal biopsies of patients with acute colitis. Methods: All mucosal mononuclear phagocytic cells in rectal biopsies of patients with acute Campylobacter colitis (n = 5), shigellosis (n = 5), and cholera (n = 10) were evaluated ultrastructurally and compared with those in controls (n = 5). Results: Mononuclear phagocytic cells in the superficial rectal mucosa showed a higher prevalence of ultrastructural features of activation in Campylobacter colitis and cholera than in controls. A lower prevalence of features of activation with increased monocytes was seen in shigellosis. Cells with the ultrastructural morphology of activated dendritic cells constituted 41% and 45% of all mononuclear phagocytic cells in two of five patients with Campylobacter colitis and 4–22% of cells in four of 10 patients with cholera. Their presence in patients with Campylobacter colitis was associated with significant surface epithelial damage and prominent acute inflammatory changes in the mucosa. Conclusions: This is the first ultrastructural study to show activated macrophages and dendritic cells in vivo in acute Campylobacter colitis and cholera. Dendritic cell activation occurred early in the clinical course of these infections. Surface epithelial damage may play a role in the activation of dendritic cells. 相似文献
88.
89.
Gurpreet Singh Dhillon Shohreh Honarbakhsh Antonio Di Monaco Ann Elizabeth Coling Kernerov Lenka Francesca Pizzamiglio Ross J. Hunter Rodney Horton Moussa Mansour Andrea Natale Vivek Reddy Massimo Grimaldi Petr Neuzil Claudio Tondo Richard J. Schilling 《Journal of cardiovascular electrophysiology》2020,31(6):1259-1269
90.