30 research outputs found
L-Glutamine therapy reduces endothelial adhesion of sickle red blood cells to human umbilical vein endothelial cells
BACKGROUND: We have previously demonstrated that therapy with orally administered L-glutamine improves nicotinamide adenosine dinucleotide (NAD) redox potential of sickle red blood cells (RBC). On further analysis of L-glutamine therapy for sickle cell anemia patients, the effect of L-glutamine on adhesion of sickle RBC to human umbilical vein endothelial cells (HUVEC) was examined. METHODS: The first part of the experiment was conducted with the blood samples of the 5 adult sickle cell anemia patients who had been on L-glutamine therapy for at least 4 weeks on a dosage of 30 grams per day compared to those of patient control group. In the second part of the experiment 6 patients with sickle cell anemia were studied longitudinally. Five of these patients were treated with oral L-glutamine 30 grams daily and one was observed without treatment as the control. t-test and paired t-test were used for determination of statistical significance in cross-sectional and longitudinal studies respectively. RESULTS: In the first study, the mean adhesion to endothelial cells with the autologous plasma incubated cells were 0.97 ± 0.45 for the treated group and 1.91 ± 0.53 for the nontreated group (p < 0.02). Similarly with lipopolysaccharide (LPS) incubated cells the mean adhesion to endothelial cells were 1.39 ± 0.33 for the treated group and 2.80 ± 0.47 for the untreated group (p < 0.001). With the longitudinal experiment, mean decrease in the adhesion to endothelial cells was 1.13 ± 0.21 (p < 0.001) for the 5 treated patients whereas the control patient had slight increase in the adhesion to endothelial cells. CONCLUSION: In these studies, oral L-glutamine administration consistently resulted in improvement of sickle RBC adhesion to HUVEC. These data suggest positive physiological effects of L-glutamine in sickle cell disease
Genome-Wide Survey and Expression Profiling of CCCH-Zinc Finger Family Reveals a Functional Module in Macrophage Activation
Previously, we have identified a novel CCCH zinc finger protein family as negative regulators of macrophage activation. To gain an overall insight into the entire CCCH zinc finger gene family and to evaluate their potential role in macrophage activation, here we performed a genome-wide survey of CCCH zinc finger genes in mouse and human. Totally 58 CCCH zinc finger genes in mouse and 55 in human were identified and most of them have not been reported previously. Phylogenetic analysis revealed that the mouse CCCH family was divided into 6 groups. Meanwhile, we employed quantitative real-time PCR to profile their tissue expression patterns in adult mice. Clustering analysis showed that most of CCCH genes were broadly expressed in all of tissues examined with various levels. Interestingly, several CCCH genes Mbnl3, Zfp36l2, Zfp36, Zc3h12a, Zc3h12d, Zc3h7a and Leng9 were enriched in macrophage-related organs such as thymus, spleen, lung, intestine and adipose. Consistently, a comprehensive assessment of changes in expression of the 58 members of the mouse CCCH family during macrophage activation also revealed that these CCCH zinc finger genes were associated with the activation of bone marrow-derived macrophages by lipopolysaccharide. Taken together, this study not only identified a functional module of CCCH zinc finger genes in the regulation of macrophage activation but also provided the framework for future studies to dissect the function of this emerging gene family
Identification of amino acid residues responsible for von Willebrand factor binding to sulfatide by charged-to-alanine-scanning mutagenesis
von Willebrand factor (VWF) performs its hemostatic functions through binding to various proteins. The A1 domain of VWF contains binding sites of not only physiologically important ligands, but also exogenous modulators that induce VWF-platelet aggregation. Sulfatides, 3-sulfated galactosyl ceramides, that are expressed on oligodendrocytes, renal tubular cells, certain tumor cells and platelets, have been suggested to interact with VWF under some pathological conditions. The binding of VWF to sulfatide requires the A1 domain, but its binding sites have not been precisely identified. Here, we report that alanine mutations at Arg1392, Arg1395, Arg1399 and Lys1423 led to decreased VWF–sulfatide binding. These sites have been reported to be the binding sites for platelet membrane glycoprotein (GP) Ib and/or snake venom botrocetin, and, interestingly, are identical to the monoclonal antibody (mAb) NMC4 epitope previously reported to inhibit the VWF-GPIb interaction. We observed that NMC4 also inhibited VWF interaction with sulfatides in a dose-dependent manner. Thus, we conclude that VWF binding sites of sulfatide overlap those of platelet GPIb and botrocetin
Endothelial cell interactions with sickle cell, sickle trait, mechanically injured, and normal erythrocytes under controlled flow
Endothelial cell interactions with sickle cell, sickle trait, mechanically injured, and normal erythrocytes under controlled flow
Storage duration and white blood cell content of red blood cell (RBC) products increases adhesion of stored RBCs to endothelium under flow conditions
Restoration of Retinal Development in Vsx2 Deficient Mice by Reduction of Gdf11 Levels
The visual system homeobox 2 (Vsx2/Chx10) gene is required for proper eye development in vertebrates. In mouse, mutations in Vsx2 cause micro-ophthalmia, optic nerve aplasia, and failed retinal development, as well as aberrant retinal lamination. GDF11, a member of the TGF-β superfamily of signaling molecules known to function as an autocrine negative regulator of sensory neuron neurogenesis, has also been shown to have dramatic effects on retinal development: Absence of Gdf11 results in an increase in numbers of retinal ganglion cells, resulting from changes in the fates of retinal stem/progenitor cells in Gdf11 null retinas. In the present study, we performed genetic manipulations of the GDF11 signaling system to determine whether alterations in Gdf11 activity levels can improve retinal development in Vsx2-null mice. We found that removal of Gdf11 alleles in Vsx2 mice can rescue retinal development and thickness to a substantial extent, and partially restores the expression of genes important for the development of specific types of retinal neurons. The molecular mechanism(s) by which reduction of Gdf11 activity enables rescue of retinal development in Vsx2 mutant animals is currently being investigated, and should provide important insights for potential treatment of retinal dystrophies. © 2012 Springer Science+Business Media, LLC. orJ/or
Necessity for surgery in children with gastrooesophageal reflux and supraoesophageal symptoms
BACKGROUND/PURPOSE: The majority of gastrooesophageal reflux (GER) manifestations in children are supraoesophageal, and "spitting/posseting" is "the tip of the iceberg" because most reflux episodes are not regurgitated. Aim of the present study was to prospectively evaluate the incidence of gastrooesophageal reflux and the incidence of antireflux surgery in patients with difficult-to-treat respiratory symptoms.
PATIENTS AND METHODS: Five hundred and ninety-five children with difficult-to-treat respiratory symptoms were prospectively enrolled in a blind study looking for the correlation between clinical presentation (asthma or non-asthma), oesophageal pH monitoring, X-ray barium meal, broncho-alveolar lavage, necessity for surgery, and outcome.
RESULTS: pH monitoring was anomalous in 47% of patients with asthma (group A) and in 43% of those who did not have asthma as main symptom (group B). Overall, 48 patients finally underwent anti-reflux surgery (8%) as anti-reflux medical treatment did not ensure stable benefits. No major surgical complications were experienced. Postoperatively, respiratory symptoms improved strongly (Visick 1) in 69% of cases, moderately (Visick 2) in 27%, while clinical worsening (Visick 4) was observed in 4%.
CONCLUSIONS: The results of this study stress the importance of symptoms, clinical response to anti-reflux medical treatment and broncho-alveolar lavage compared to classical pH parameters in the decision-making process for patients with difficult-to-treat supraoesophageal symptoms. To date no single tool alone has proved to be diagnostic in these patients. Fundoplication is recommended only when a relationship between supraoesophageal symptoms and gastrooesophageal reflux is strongly suspected