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OBJECTIVE: In Crohn's disease (CD) a Th-1 dominant immune reaction is induced, which could be associated with genetic predisposition. Several previous studies have investigated the roles of CD14, heat-shock protein (Hsp)70 and IL-10 gene polymorphisms in the development of the disease. The results are contradictory and inter-racial differences are implicated. Therefore, this phenomenon was evaluated in well-documented Caucasian patients with CD in order to verify the clinical importance of these polymorphisms. MATERIAL AND METHODS: The genomic DNA of 133 patients with CD and that of 75 healthy controls were examined. CD was divided into subgroups according to the Vienna classification. An arbitrary classification system based on disease severity was also applied, which was determined according to the therapeutic intervention. The CD14 (-159 C-->T) promoter gene polymorphism was investigated by melting-point analysis. The IL-10 (-1082 G-->A) and Hsp70-2 (1267 A-->G) gene polymorphisms were detected by RFLP (restriction fragment length polymorphism). RESULTS: None of the allele frequencies of the examined polymorphisms differed significantly between the patient and control populations. Neither the CD14 nor the IL-10 polymorphisms exhibited any correlation with the development or with the progression of the disease. With regard to Hsp70-2 gene polymorphism, those patients who carry at least one A allele have a significantly lower probability of the need for surgical intervention. CONCLUSIONS: Allele A of the Hsp70-2 gene may be associated with a less severe form of CD, suggesting the clinical value of the genotype assessment. The genetic determination of the defense mechanisms in CD appears to be associated with the polymorphism of the Hsp70-2 gene rather than that of the CD14 or IL-10 genes.  相似文献   
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Purpose

To describe the applied anatomy of a minimally invasive muscle-splitting approach used to reach the posterior aspect of the C1–C2 complex.

Summary of background data

Atlantoaxial fusion using a midline posterior approach and polyaxial screw and rod system is widely used. Although minimally invasive variations of this technique have been recently reported, the complex applied anatomy of these approaches has not been described. The C1–C2 complex represents an unique challenge because of its bony and vascular anatomy. In this study, the applied anatomy and feasibility of this technique are examined on cadavers.

Methods

The microsurgical anatomy of the upper cervical spine is examined on a formalin-fixed and on a fresh cadaver. The muscle-splitting approach is performed on 12 fresh cadavers using this technique.

Results

The minimally invasive muscle-splitting approach is described in detail. Relevant anatomy and bony landmarks that aid screw placement in C1 and C2 could be well visualized. Using this approach, we were able to reach the lateral mass of the atlas and the inferior articular process and pars interarticularis of the axis in all of the nine cadavers. We placed mini polyaxial screws in C1 lateral mass and C2 pars interarticularis in four cadavers according to the technique described by Harms and Melcher.

Conclusions

Using this approach, it was possible to reach the posterior aspect of C1 and C2; the relevant anatomy needed to perform a C1–C2 fusion could be well visualized.  相似文献   
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Lesch-Nyhan syndrome (LNS) is a chronic, progressive neurodevelopmental disorder causing motor and behavioral dysfunction due to decreased synthesis of the enzyme hypoxantine-guanine phosphoribosyltransferase (HPRT). Affected boys have mental retardation, delayed development, extrapyramidal motor disturbances and self-injuring behavior. As hematopoietic stem cell transplantation (HSCT) has been shown to be effective in several neurodevelopmental inborn errors, we hypothesized that it could be favorable in LNS as well. Following a myeloablative conditioning regimen (busulphan 3.2 mg/kg/day for 4 days, cyclophosphamide 60 mg/kg/day for 2 days with ATG Thymoglobin 2.5 mg/kg/day for 4 days) an unrelated umbilical cord blood unit was transfused at the age of 2 years. The graft was a 6/6 HLA-matched at HLA-A, B loci by antigen level, and at DRB1 by allelic level typing. Infused total nucleated cell dose was 3.6 × 10e7 per kilogram body weight. Serum HPRT levels reached normal values by the end of the sixth month post transplant. Slow neurodevelopmental improvement seen during the three-year follow-up and the missing self-injuring behavior can be considered as a proof for the presence of enzyme-competent cells behind the blood–brain barrier.  相似文献   
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Introduction

Acute severe asthma is a life-threatening form of bronchial constriction in which the progressively worsening airway obstruction is unresponsive to the usual appropriate bronchodilator therapy. Pathophysiological changes restrict airflow, which leads to premature closure of the airway on expiration, impaired gas exchange, and dynamic hyperinflation (“air-trapping”). Additionally, patients suffering from asthma for a prolonged period of time usually have serious comorbidities. These conditions constitute a challenge during the treatment of this disease. Therapeutic interventions are designed to reduce airway resistance and improve respiratory status. To achieve therapeutic goals, appropriate bronchodilator treatment is indispensable, and mechanical ventilation under adequate sedation may also be required. The volatile anesthetic agent, sevoflurane, meets both criteria; therefore, its use can be beneficial and should be considered.

Case presentation

A 67-yr-old Caucasian male presented with acute life-threatening asthma provoked by an assumed upper airway infection and non-steroidal anti-inflammatory drug antipyretics, complicated by chronic atrial fibrillation and hemodynamic instability. Due to frequent premature ventricular contractions, conventional treatment was considered unsafe and discontinued, and sevoflurane inhalation was initiated via the AnaConDa? (Anaesthetic Conserving Device). Symptoms of life-threatening bronchospasm resolved, and the patient’s respiratory status improved within hours. Adequate sedation was also achieved without any hemodynamic adverse effects.

Conclusion

The volatile anesthetic agent, sevoflurane, is used widely in anesthesia practice. Its utility for treatment of refractory bronchospasm has been appreciated for years; however, its administration was difficult within the environment of the intensive care unit due to the need for an anesthesia machine and a scavenging system. The introduction of the AnaConDa eliminates these obstacles and makes the use of sevoflurane safe and simple. Our case report reveals the potential of sevoflurane as a “two-in-one” (bronchodilator and sedative) drug to treat a severe acute asthma attack.
  相似文献   
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Recent advances in nanoscale bioreplication processes present the potential for novel basic and applied research into organismal behavioral processes. Insect behavior potentially could be affected by physical features existing at the nanoscale level. We used nano-bioreplicated visual decoys of female emerald ash borer beetles (Agrilus planipennis) to evoke stereotypical mate-finding behavior, whereby males fly to and alight on the decoys as they would on real females. Using an industrially scalable nanomolding process, we replicated and evaluated the importance of two features of the outer cuticular surface of the beetle’s wings: structural interference coloration of the elytra by multilayering of the epicuticle and fine-scale surface features consisting of spicules and spines that scatter light into intense strands. Two types of decoys that lacked one or both of these elements were fabricated, one type nano-bioreplicated and the other 3D-printed with no bioreplicated surface nanostructural elements. Both types were colored with green paint. The light-scattering properties of the nano-bioreplicated surfaces were verified by shining a white laser on the decoys in a dark room and projecting the scattering pattern onto a white surface. Regardless of the coloration mechanism, the nano-bioreplicated decoys evoked the complete attraction and landing sequence of Agrilus males. In contrast, males made brief flying approaches toward the decoys without nanostructured features, but diverted away before alighting on them. The nano-bioreplicated decoys were also electroconductive, a feature used on traps such that beetles alighting onto them were stunned, killed, and collected.Biomimicry of insect visual communication signals has received much recent attention, with growing interest in nanofabrication processes that result in artificially produced structural colors (1) such as those emanating from the ridges on butterfly wing scales (2). The fidelity of the nanoreplication of visual signals with communication value to such organisms has been underexplored, however. Visually induced behavior in arthropods often integrates color and edge-motion detection, with interactions often involving a variety of biotic and abiotic entities, making it difficult to reproduce experimentally (3).Bioreplication of visual signaling structures might be manipulated so as to provide insight into the mechanisms of such signaling processes; however, all currently known examples of bioreplicated nanostructures that have been created to affect behavior involve unicellular movements across particular textured environments (47), rather than directed to evoke responses of specialized sensory organs of more complex multicellular organisms. Bioreplicated structures emitting behaviorally effective visual cues also may be useful for such practical purposes as the monitoring and detection of pest species, but the communication efficacy of the bioreplica needs to be validated under field conditions using naturally occurring (i.e., wild) populations.In contrast, biomimicry of chemical signals, such as insect pheromones, has been a burgeoning field for more than half a century. Synthetically reproduced pheromones have been successfully applied under field conditions to manipulate insect behavior for invasive species pest detection, population monitoring of endemic species, and disruption of mating. Thousands of studies have described the essential components of nanoscale levels (nanograms) of semiochemical signals that trigger behavioral responses, such as upwind flight for mating (8), alarm responses (9), and trail following (10). Furthermore, neurophysiological techniques have elucidated how these signals are transduced by peripheral sensory organs (11) and integrated into odor sensations in the higher processing centers of the insect brain (12). In the realm of applied science, these insights have led to trapping protocols for pest population detection, attract-and-kill protocols, and mating disruption (13). Visually attractive features of trapping technologies generally have not been approached with such rigor, however, and are usually optimized by simple manipulations of trap colors without efforts to understand the underlying mechanisms of visual attraction.In an effort to initiate such an approach to manipulation of visual signaling systems, we used an industrially scalable nano-bioreplication technique (14) to produce high-fidelity replicas of the structural features of the cuticle of the hard wing covers (elytra) of an invasive buprestid beetle pest, the emerald ash borer (Agrilus planipennis). This species is a tree-killing pest of Asian origin whose visual signal is emitted by the elytra of a female at rest on an ash leaf in direct sunlight, which triggers attraction of flying males that are patrolling the canopy. Male responses unfold as rapid flights toward the females from heights of up to 2 m, usually terminating with the males alighting directly on the females and attempting to copulate (15). This “paratrooper” descent behavior by flying A. planipennis males in the field can be repeatedly evoked by affixing dead A. planipennis females to ash leaves (15, 16). Furthermore, various other potentially invasive European and North American tree-feeding Agrilus species have been observed performing similar stereotypical inflight descents onto dead beetle decoys affixed to the leaves of preferred host trees (17, 18). Such approaches are often seen to congeneric, heterospecific targets. One such species, the two-spotted oak borer, Agrilus biguttatus, that is similar in size and habits to A. planipennis is known to kill oak trees within its native range in Europe (19), particularly after drought (20) or defoliation events (21).The base colors of many metallic-colored beetles, including buprestid beetles (Fig. 1A), are known to be structurally produced by the repeated alternation of cuticle layers (Fig. 1D) with different refractive indices (22, 23). This periodically multilayered assemblage functions as a quarter-wave Bragg stack reflector in a particular spectral regime (2) and is thus highly effective for creating a color of narrow specificity in sunlight, unlike many naturally occurring pigments. The reflected light is also affected by regular fine-scale topographic features of the surface, including thousands of sharp spicules each emitting green to yellow colors, which are further scattered by numerous spines (Fig. 1 B and C). Many of the physical attributes of the A. planipennis cuticle that produce its attractive visual signal have been replicated by a process that involves the stamping of a polymer quarter-wave Bragg stack reflector with a set of dies cast from the actual elytra of a female A. planipennis (Fig. 2) (14).Open in a separate windowFig. 1.Structural color and surface topography of A. planipennis wings. (A) Optical microscopy showing a dorsal view of the beetle elytron. (B) Higher-magnification optical microscopy showing spines and cilia. (C) Scanning electron micrograph showing a higher-resolution image of the surface topography. (D) Transmission electron micrograph of a cross-section of an elytron, showing four alternating layers of differing refractive indices. (C and D are reprinted with permission from ref. 14.)Open in a separate windowFig. 2.Nano-bioreplicated decoy characteristics. (A) Optical microscopy of the nickel die. (B) Scanning electron micrograph of a nickel die used for bioreplication, showing a similar structure as the A. planipennis surface (Fig. 1), but without the cilia. (C) Optical microscopy of the dorsal view of a nano-bioreplicated A. planipennis decoy that reproduces the surface structure of the beetle and is colored by metallic paint. (A and B are reprinted with permission from ref. 14.)Here we report on direct field observations of A. planipennis and A. biguttatus male behavior toward natural beetle decoys versus three types of synthetic decoys with varying degrees of verisimilitude with respect to the fidelity of bioreplication. These synthetic decoys included: (i) a bioreplicated decoy created by a nanomolding process and colored with a polymer functioning as a Bragg reflector; (ii) another bioreplicated decoy created by a nanomolding process and colored with a metallic green paint; and (iii) a 3D-printed decoy consisting of a smooth polymer surface without a nanomolded bioreplicated surface structure, also colored with green metallic paint. We investigated whether the nanomolding process could create light-scattering patterns similar to those of real decoys by observing light emissions resulting from the application of a white laser to the surfaces of real and synthetic decoys in a dark room. We hypothesized that a sufficient degree of verisimilitude with respect to color and fine-scale topological features of the elytra could be achieved through the bioreplication process to elicit inflight mating approaches and landings similar to those evoked by real beetles. We also incorporated the bioreplicated decoys into a trapping system in which the electroconductive properties of the decoy are used to electrocute male beetles when they approach and alight on the decoys.  相似文献   
30.
Background: Lumefantrine, a commonly used antimalarial drug, inhibits hemozoin formation in parasites. Several other antimalarial substances counteract parasitemia by triggering suicidal death or eryptosis of infected erythrocytes. Eryptosis is characterized by cell shrinkage and cell membrane scrambling leading to phosphatidylserine-exposure at the erythrocyte surface. Signaling involved in eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i), formation of ceramide, oxidative stress and/or activation of p38 kinase, protein kinase C (PKC), or caspases. The present study explored, whether lumefantrine stimulates eryptosis. Methods: Cell volume has been estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, [Ca2+]i from Fluo3-fluorescence, reactive oxygen species from 2'',7''-dichlorodihydrofluorescein-diacetate fluorescence, content of reduced glutathione (GSH) from mercury orange fluorescence, and ceramide abundance from binding of fluorescent antibodies in flow cytometry. Results: A 48 h exposure to lumefantrine (3 µg/mL) was followed by a significant increase of annexin-V-binding without significantly altering forward scatter, [Ca2+]i, ROS formation, reduced GSH, or ceramide abundance. The annexin-V-binding following lumefantrine treatment was not significantly modified by p38 kinase inhibitors SB203580 (2 μM) and p38 Inh III (1 μM), PKC inhibitor staurosporine (1 µM) or pancaspase inhibitor zVAD (1 or 10 µM). Conclusions: Lumefantrine triggers cell membrane scrambling, an effect independent from entry of extracellular Ca2+, ceramide formation, ROS formation, glutathione content, p38 kinase, PKC or caspases.  相似文献   
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