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991.
Wiener Medizinische Wochenschrift - Gastrointestinal tuberculosis (TB) is a rare manifestation in low TB-incidence countries such as Austria. It is usually seen in immunocompromised...  相似文献   
992.
Transmigration through the liver endothelium is a prerequisite for the homeostatic balance of intrahepatic T cells and a key regulator of inflammatory processes within the liver. Extravasation into the liver parenchyma is regulated by the distinct expression patterns of adhesion molecules and chemokines and their receptors on the lymphocyte and endothelial cell surface. In the present study, we investigated whether liver sinusoidal endothelial cells (LSEC) inhibit or support the chemokine-driven transmigration and differentially influence the transmigration of pro-inflammatory or anti-inflammatory CD4(+) T cells, indicating a mechanism of hepatic immunoregulation. Finally, the results shed light on the molecular mechanisms by which LSEC modulate chemokine-dependent transmigration. LSEC significantly enhanced the chemotactic effect of CXC-motif chemokine ligand 12 (CXCL12) and CXCL9, but not of CXCL16 or CCL20, on naive and memory CD4(+) T cells of a T helper 1, T helper 2, or interleukin-10-producing phenotype. In contrast, brain and lymphatic endothelioma cells and ex vivo isolated lung endothelia inhibited chemokine-driven transmigration. As for the molecular mechanisms, chemokine-induced activation of LSEC was excluded by blockage of G(i)-protein-coupled signaling and the use of knockout mice. After preincubation of CXCL12 to the basal side, LSEC took up CXCL12 and enhanced transmigration as efficiently as in the presence of the soluble chemokine. Blockage of transcytosis in LSEC significantly inhibited this effect, and this suggested that chemokines taken up from the basolateral side and presented on the luminal side of endothelial cells trigger T cell transmigration. CONCLUSION: Our findings demonstrate a unique capacity of LSEC to present chemokines to circulating lymphocytes and highlight the importance of endothelial cells for the in vivo effects of chemokines. Chemokine presentation by LSEC could provide a future therapeutic target for inhibiting lymphocyte immigration and suppressing hepatic inflammation.  相似文献   
993.

OBJECTIVE

There is growing evidence that vitamin D deficiency plays a role in the development and the course of inflammatory bowel disease (IBD). However, the correlation between vitamin D deficiency and clinical parameters in IBD is still not completely understood.

METHODS

A retrospective study of IBD patients was performed. Vitamin D values were analyzed, regardless of vitamin D substitution administration, and correlated with clinical parameters such as medical therapy, anatomical situation, location of the disease and disease activity. Level of 25‐hydroxyvitamin D [25(OH)D] <50 nmoL/L was regarded as vitamin D deficiency and <75 nmoL/L as insufficiency.

RESULTS

In total, 208 IBD patients were analyzed, including 123 with Crohn's disease (CD) and 85 with ulcerative colitis (UC). Therapy with azathioprine did not affect the vitamin D values of either disease entity. But CD patients benefited from therapy with tumor necrosis factor‐α inhibitor and exhibited significantly higher vitamin D levels than those without. Furthermore, significantly lower vitamin D levels were found if CD was located in the small bowel or if the small bowel had been resected. Moreover, significantly lower levels of vitamin D were detectable for high disease activity (reflected by high simple clinical colitis activity index values) in patients with UC.

CONCLUSIONS

Vitamin D deficiency is common in patients with IBD. However, certain clinical situations lead to significantly lower vitamin D levels and may therefore require close monitoring for vitamin D deficiency.  相似文献   
994.
995.
AIM: To register chromosomal anomalies, syndromes and extracardiac malformations in patients with Congenital heart defects (CHDs). METHOD: Population-based prospective observational study. RESULTS: Of 57 027 live births during 1982-2005, CHDs were detected in 662 (11.6 per 1000), of whom 146 (22%) had associated anomalies. Of these 52 (36%) had chromosomal anomalies (exclusive microdeletions), 26 (18%) genetic syndromes/microdeletions, 1 (0.7%) a teratogenous syndrome and 67 (46%) extracardiac malformations. In perimembraneous ventricular septal defects (VSDs), associated anomalies occurred in 22 of 70 (31%) compared to 27 of 298 (9%) in VSDs located in the muscular part of the septum (p < 0.0001). The prevalence of CHDs with associated disorders increased significantly from the cohort born during 1982-1993 to those born during 1994-2005 (2.0 vs. 3.1 per 1000, respectively; p < 0.0001), mainly caused by an increase of chromosomal trisomies (0.5 vs. 1.1 per 1000; p = 0.026). The percentage of women giving live birth at 35 years of age or more was 7.6% for the period 1982-1993 compared to 13.4% for 1994-2005 (p = 0.001). CONCLUSIONS: Chromosomal anomalies, syndromes and extracardiac malformations occurred in nearly one-fourth of CHD cases. Muscular VSDs had a low prevalence of such conditions. The prevalence of CHDs with chromosomal trisomies increased, and was probably related to an increasing age of women giving birth.  相似文献   
996.
The aim of the present work was to investigate the preparation of nanoparticles as a potential drug carrier and targeting system for the treatment of inflammatory bowel disease. Rolipram was chosen as the model drug to be incorporated within nanoparticles. Pressure homogenization-emulsification (PHE) with a microfluidizer or a modified spontaneous emulsification solvent diffusion method (SESD) were used in order to select the most appropriate preparation method. Poly(epsilon-caprolactone) has been used for all preparations. The drug loading has been optimized by varying the concentration of the drug and polymer in the organic phase, the surfactants (polyvinyl alcohol, sodium cholate) as well as the volume of the external aqueous phase. The rolipram encapsulation efficiency was high (>85%) with the PHE method in all cases, whereas with the SESD method encapsulation efficiencies were lower (<40%) when lower surfactant concentrations and reduced volume of aqueous phase were used. Release profiles were characterized by a substantial initial burst release with the PHE method (25-35%) as well as with the SESD method (70-90%). A more controlled release was obtained after 2 days of dissolution with the PHE method (70-90%), no further significant drug release was observed with the SESD method.  相似文献   
997.
Around 40% of newly diagnosed lung cancer patients are Stage IV, where the improvement of survival and reduction of disease-related adverse events is the main goal for oncologists. In this scenario, we present preclinical evidence supporting the use of ABTL0812 in combination with chemotherapy for treating advanced and metastatic Nonsmall cell lung adenocarcinomas (NSCLC) and squamous carcinomas. ABTL0812 is a new chemical entity, currently in Phase 1b/2a clinical trial for advanced squamous NSCLC in combination with paclitaxel and carboplatin (P/C), after successfully completing the first-in-human trial where it showed an excellent safety profile and signs of efficacy. We show here that ABTL0812 inhibits Akt/mTOR axis by inducing the overexpression of TRIB3 and activating autophagy in lung squamous carcinoma cell lines. Furthermore, treatment with ABTL0812 also induces AMPK activation and ROS accumulation. Moreover, combination of ABTL0812 with chemotherapy markedly increases the therapeutic effect of chemotherapy without increasing toxicity. We further show that combination of ABTL0812 and chemotherapy induces nonapoptotic cell death mediated by TRIB3 activation and autophagy induction. We also present preliminary clinical data indicating that TRIB3 could serve as a potential novel pharmacodynamic biomarker to monitor ABTL0812 activity administered alone or in combination with chemotherapy in squamous NSCLC patients. The safety profile of ABTL0812 and its good synergy with chemotherapy potentiate the therapeutic potential of current lines of treatment based on chemotherapy regimens, arising as a promising option for improving these patients therapeutic expectancy.  相似文献   
998.
999.
Preparatory trunk motion accompanies rapid upper limb movement   总被引:12,自引:0,他引:12  
 Evaluation of trunk movements, trunk muscle activation, intra-abdominal pressure and displacement of centres of pressure and mass was undertaken to determine whether trunk orientation is a controlled variable prior to and during rapid bilateral movement of the upper limbs. Standing subjects performed rapid bilateral symmetrical upper limb movements in three directions (flexion, abduction and extension). The results indicated a small (0.4–3.3°) but consistent initial angular displacement between the segments of the trunk in a direction opposite to that produced by the reactive moments resulting from limb movement. Phasic activation of superficial trunk muscles was consistent with this pattern of preparatory motion and with the direction of motion of the centre of mass. In contrast, activation of the deep abdominal muscles was independent of the direction of limb motion, suggesting a non-direction specific contribution to spinal stability. The results support the opinion that feedforward postural responses result in trunk movements, and that orientation of the trunk and centre of mass are both controlled variables in relation to rapid limb movements. Received: 4 March 1998 / Accepted: 24 June 1998  相似文献   
1000.
INTRODUCTION: Most decompression procedures induce the formation of asymptomatic venous gas bubbles. They can be classified as "silent bubbles," which are asymptomatic compared to paradoxical arterialization of venous gas emboli, which can lead to serious neurologic damage. The penetration of such gas bubbles into the arterial circulation is due to pulmonary barotrauma, intrapulmonary (I-P) passage after massive bubble formation ("chokes"), or intracardiac shunting. Venous gas bubbles can be monitored and graded with echocardiographic scanning. CASE: We believe this is the first case to be reported of a recreational diver who, after surfacing from a dive, developed grade 5 ("white-out") venous gas bubbles in the right heart with evidence of I-P shunt at rest without any symptoms of decompression sickness. Grade 4 gas bubbles were found on the left side of the heart, indicating significant I-P shunting even at rest. CONCLUSION: We observed venous bubbles crossing through the I-P shunt during post-dive recovery at rest in a diver who developed "white out" of venous bubbles. Previously, the maximum bubble grade 5 had been observed in experimental animals, but not in humans. Moreover, a significant bubble grade was found on the left side of the heart, indicating a need for further studies to investigate the mechanisms of post-dive changes in peripheral and central circulation.  相似文献   
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