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31.
Klimiuk PA Sierakowski S Domysławska I Fiedorczyk M Chwiećko J 《Archivum immunologiae et therapiae experimentalis》2004,52(1):36-42
INTRODUCTION: The purpose of this study was to determine the effect of repeated infusions of infliximab, a chimeric anti-tumor necrosis factor (anti-TNF)-alpha antibody, on the levels of soluble adhesion molecules and vascular endothelial growth factor (VEGF) in patients with active rheumatoid arthritis (RA). MATERIALS AND METHODS: The treatment design consisted of 9 infusions of infliximab (3 mg/kg) at weeks 0, 2, 6, and every 8 weeks thereafter. All patients had been receiving methotrexate (MTX; 7.5-20 mg/week). Serum levels of soluble intercellular adhesion molecule (sICAM)-1, vascular cell adhesion molecule (sVCAM)-1, E-selectin (sE-selectin), and VEGF were measured by ELISA at weeks 0, 2, 6, 14, and 38 prior to infusion, and at week 62. RESULTS: A remarkable decrease in serum sICAM-1 (p<0.001), sVCAM-1 (p<0.01), sE-selectin (p<0.01) and VEGF (p<0.001) levels was observed in RA patients after the initial dose of infliximab. The second administration of the drug was followed by an even more significant suppression of serum sICAM-1, sVCAM-1, sE-selectin, and VEGF (p<0.001 in all cases). Further infliximab infusions also significantly reduced serum soluble adhesion molecules and VEGF concentrations, although these were less effective. Infliximab treatment induced a significant decrease in the number of monocytes observed until the end of the study. CONCLUSIONS: Our study, besides a rapid suppression of disease activity, showed that serum soluble adhesion molecules and VEGF concentrations are down-regulated following anti-TNF-alpha antibody therapy combined with MTX. Repeated doses of infliximab sustained the reductions in the soluble adhesion molecules and VEGF concentrations, although they were less effective than the first and second infusions of infliximab. 相似文献
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Wieslaw W. Pawlik Piotr Gustaw Eugene D. Jacobson Ryszard Sendur Krzysztof Czarnobilski 《Pflügers Archiv : European journal of physiology》1995,429(3):301-305
It has long been recognized that intestinal blood flow increases at mealtimes. Mesenteric hyperaemia is also evoked by activation of sensory peptidergic nerves. Our studies explored the possible role of endogenous nitric oxide (NO) in the rat intestinal vasodilator response to luminal instillation of an oleic acid plus bile mixture before and after acute intrajejunal instillation of capsaicin and after chronic pretreatment with capsaicin. In anaesthetized rats we measured jejunal blood flow (BF) with an ultrasonic Doppler flowmeter and systemic arterial pressure (AP) with a pressure transducer. Intestinal perfusion with 80 mM oleic acid in bile increased BF by 98±12%. Instillation of 4 mg of capsaicin into the jejunal lumen initially increased BF by 42±9% but was followed by vasoconstriction. Inhibition of NO synthase with 25 mg/kg i.v. N-nitro-L-arginine (L-NNA) decreased BF by 27±5% and increased AP by 37±11%. After treatment with L-NNA and after acute and chronic administration of capsaicin, the bile-oleate-induced maximal increases in BF above control levels were 42±7%, 65±12%, and 58±8%, respectively. The observed inhibitory effect of L-NNA on the intestinal hyperaemic response to the bile-oleate mixture was reversed by pretreatment with L-arginine (100 mg/kg i.V.). In capsaicin pretreated rats the subsequent bile-oleate-induced hyperaemia was reduced in magnitude but the inhibitory effects of L-NNA were proportionately the same as in animals not receiving capsaicin. These findings support the hypothesis that NO is involved with bile-oleate-induced mesenteric hyperaemia. 相似文献
34.
Krzyzak AT Jasiński A Weglarz WP Adamek D Sagnowskil P Baj M 《Acta neurobiologiae experimentalis》2005,65(3):255-264
Magnetic Resonance Diffusion Tensor Imaging (DTI) of the control and traumatic injured spinal cord of a rat in vitro is reported. Experiments were performed on excised spinal cords from 10 Wistar rats, using a home-built 6.4 T MR microscope. MRI and histopathological results were compared. Presented results show that DTI of the spinal cord, perfused with formalin 10 minutes after the injury, can detect changes in water diffusion in white matter (WM) and in gray matter (GM), in areas extending well beyond the region of direct impact. Histology of neurons of the GM shows changes that can be attributed to ischemia. This is in agreement with the observed decrease of diffusion in the injured regions, which may be attributed to the cytotoxic edema due to ischemia. However, the diffusion changes in highly anisotropic WM seem to be caused by a direct action of mechanical force of impact, which significantly distorts the nerve fibers. 相似文献
35.
Vinod Dasa James R.B. Eastwood Michal Podgorski Heewon Park Christopher Blackstock Tetyana Antoshchenko Piotr Rogala Tadeusz Bieganski S. Michal Jazwinski Malwina Czarny‐Ratajczak 《American journal of medical genetics. Part A》2019,179(4):534-541
Mutations in the COMP, COL9A1, COL9A2, COL9A3, MATN3, and SLC26A2 genes cause approximately 70% of multiple epiphyseal dysplasia (MED) cases. The genetic changes involved in the etiology of the remaining cases are still unknown, suggesting that other genes contribute to MED development. Our goal was to identify a mutation causing an autosomal dominant form of MED in a large multigenerational family. Initially, we excluded all genes known to be associated with autosomal dominant MED by using microsatellite and SNP markers. Follow‐up with whole‐exome sequencing analysis revealed a mutation c.2032G>A (p.Gly678Arg) in the COL2A1 gene (NCBI Reference Sequence: NM_001844.4), which co‐segregated with the disease phenotype in this family, manifested by severe hip dysplasia and osteoarthritis. One of the affected family members had a double‐layered patella, which is frequently seen in patients with autosomal recessive MED caused by DTDST mutations and sporadically in the dominant form of MED caused by COL9A2 defect. 相似文献
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Treatment with continuous positive airway pressure may affect blood glucose levels in nondiabetic patients with obstructive sleep apnea syndrome 总被引:5,自引:0,他引:5
STUDY OBJECTIVES: Obstructive sleep apnea syndrome (OSAS) is often associated with impaired glucose metabolism. Data on the effects of OSAS treatment with continuous positive airway pressure (CPAP) on blood glucose and insulin resistance are conflicting. The study aimed at assessing the immediate effect of CPAP on glucose control measured with a continuous glucose monitoring system (CGMS). PARTICIPANTS AND MEASUREMENTS: Nine non-diabetes subjects with OSAS (mean age 53.0 +/- 8.0 years; body mass index 34.8 +/- 5.3 kg/m2) underwent 2 overnight polysomnographic examinations: a diagnostic study and one with CPAP treatment. Continuous glucose monitoring system (CGMS) was applied overnight on both occasions. Glucose metabolism was assessed with a 75-g oral glucose tolerance test, plasma insulin and homeostatic model assessment of insulin resistance (HOMA-IR) index. RESULTS: The mean (+/- SD) apnoea-hypopnea index (AHI) at diagnostic polysomnography was 54.3 +/- 29.3 (range 16-81). Fasting plasma insulin levels in patients with OSAS was 84.3 +/- 43.4 pM at baseline, and the HOMA-IR was 3.6 +/- 2.2. CPAP treatment in the subjects with OSAS resulted in a significant reduction in the AHI to 4.5 +/- 7.1. All of the major saturation parameters improved significantly on CPAP. CGMS showed mean glucose values significantly higher during the CPAP night than during the diagnostic night: 80 +/- 11 mg/dL versus 63 +/- 7 mg/dL (P < .01). Fasting insulin and HOMA-IR measured after the CPAP night tended to be higher than at baseline (98.4 +/- 51.0 pmol vs 84.3 +/- 43.4 pmol and 3.9 pmol +/- 2.6 vs 3.6 +/- 2.2 pmol, respectively, P > .05). CONCLUSION: CPAP treatment in nondiabetic obese patients with OSAS may have an immediate elevating effect on blood glucose. 相似文献
39.
Christina D Cota Pooneh Bagher Piotr Pelc C Owen Smith Christina R Bodner Teresa M Gunn 《Developmental dynamics》2006,235(12):3438-3447
Mahogunin Ring Finger 1 (Mgrn1) encodes a RING-containing protein with ubiquitin ligase activity that has been implicated in pigment-type switching. In addition to having dark fur, mice lacking MGRN1 develop adult-onset spongy degeneration of the central nervous system and have reduced embryonic viability. Observation of complete situs inversus in a small proportion of adult Mgrn1 mutant mice suggested that embryonic lethality resulted from congenital heart defects due to defective establishment and/or maintenance of the left-right (LR) axis. Here we report that Mgrn1 is expressed in a pattern consistent with a role in LR patterning during early development and that many Mgrn1 mutant embryos show abnormal expression of asymmetrically expressed genes involved in LR patterning. A range of complex heart defects was observed in 20-25% of mid-to-late gestation Mgrn1 mutant embryos and another 20% were dead. This finding was consistent with 46-60% mortality of mutants by weaning age. Our results indicate that Mgrn1 acts early in the LR signaling cascade and is likely to provide new insight into this developmental process as Nodal expression was uncoupled from expression of other Nodal-responsive genes in Mgrn1 mutant embryos. Our work identifies a novel role for MGRN1 in embryonic patterning and suggests that the ubiquitination of MGRN1 target genes is essential for the proper establishment and/or maintenance of the LR axis. 相似文献
40.
Dorota Skrzypczak Alicja Ewa Ratajczak Aleksandra Szymczak-Tomczak Agnieszka Dobrowolska Piotr Eder Iwona Krela-Ka
mierczak 《Nutrients》2021,13(2)
Sarcopenia is a disorder characterized by a loss of muscle mass which leads to the reduction of muscle strength and a decrease in the quality and quantity of muscle. It was previously thought that sarcopenia was specific to ageing. However, sarcopenia may affect patients suffering from chronic diseases throughout their entire lives. A decreased mass of muscle and bone is common among patients with inflammatory bowel disease (IBD). Since sarcopenia and osteoporosis are closely linked, they should be diagnosed as mutual consequences of IBD. Additionally, multidirectional treatment of sarcopenia and osteoporosis including nutrition, physical activity, and pharmacotherapy should include both disorders, referred to as osteosarcopenia. 相似文献