Spinal cord ischemia revealed by a Brown-Sequard syndrome and caused by a calcified thoracic disc extrusion with spontaneous regression: a case report and review of the literature.

BACKGROUND: Thoracic disc herniation is relatively uncommon, accounting for less than 1% of all spinal herniations. Although most often asymptomatic, they may represent a rare cause of spinal cord ischemia. CASE REPORT: We report the case of a healthy 43-year-old North African male who presented with a Brown-Sequard syndrome revealing a spinal cord ischemia caused by a thoracic disc extrusion. The initial MRI revealed a calcified disc extrusion at the level of T5-T6 without significant spinal cord compression or signal abnormality. A pattern consistent with a medullary ischemia only appeared 48 h later. The patient was treated conservatively with Aspirin and Heparin, which were discontinued later because of a negative cardiovascular work-up. The calcified disc extrusion, which was later recognized as the cause of the ischemia, decreased spontaneously over time and the patient recovered within a few months. CONCLUSIONS: Our case highlights the challenge in diagnosing and managing this uncommon condition. We propose a literature review showing the different therapeutic strategies and their corresponding clinical outcomes.

Effect of Wheatgrass Juice on Nutritional Quality of Apple, Carrot, Beet, Orange and Lemon Juice.

Fresh fruit and vegetable juices are commonly consumed as a valuable source of nutrients, while wheatgrass juice is, due to its nutritional value, used as a natural dietary supplement. The main aim of this research was to evaluate the effect of wheatgrass juice addition to apple, beet, carrot, orange, and lemon juice on total and in vitro bioaccessible concentrations of K, Ca, Mg, Mn, Fe, and Zn, vitamin C concentration, total phenolic and flavonoid content, and antioxidant activity. In comparison to other juices, wheatgrass juice had the highest total and in vitro bioaccessible concentrations of Ca, Mg, Mn, Fe, and Zn, while beet juice had the highest K concentration. Lemon and orange juices had the highest vitamin C concentration, while the highest total phenolic and flavonoid content were found in wheatgrass juice. After the addition of wheatgrass juice, Ca, Mg, Mn, and Zn concentration increased in all examined juices, vitamin C concentration increased in apple, beet, and carrot juice, total phenolic content increased in carrot juice, while total flavonoid content increased in apple, carrot, and orange juice. In comparison to the examined juices, wheatgrass juice has better nutritional value, and it could be used in a mixture with other juices to improve their nutritional value.

Identifiability of two-tree mixtures for group-based models.

Phylogenetic data arising on two possibly different tree topologies might be mixed through several biological mechanisms, including incomplete lineage sorting or horizontal gene transfer in the case of different topologies, or simply different substitution processes on characters in the case of the same topology. Recent work on a 2-state symmetric model of character change showed that for 4 taxa, such a mixture model has nonidentifiable parameters, and thus, it is theoretically impossible to determine the two tree topologies from any amount of data under such circumstances. Here, the question of identifiability is investigated for two-tree mixtures of the 4-state group-based models, which are more relevant to DNA sequence data. Using algebraic techniques, we show that the tree parameters are identifiable for the JC and K2P models. We also prove that generic substitution parameters for the JC mixture models are identifiable, and for the K2P and K3P models obtain generic identifiability results for mixtures on the same tree. This indicates that the full phylogenetic signal remains in such mixtures, and the 2-state symmetric result is thus a misleading guide to the behavior of other models.

Association of fibronectin with hypogalactosylated immunoglobulin G in gingival crevicular fluid in periodontitis.

BACKGROUND: Fibronectin (FN) can bind to immunoglobulins (Ig), influencing both the normal clearance and abnormal deposition of circulating immune complexes. This study focuses on the possible interaction between FN and IgG present in gingival crevicular fluid (GCF) of periodontitis patients and periodontally healthy controls, with the aim to determine whether such interaction may be connected with the glycosylation profile of IgG and, thus, consequentional in accumulation of proinflammatory IgG in periodontal pockets. METHODS: The study included 30 patients with initial or advanced periodontitis, and 13 periodontally healthy subjects. GCF IgG was purified and analyzed for the presence of FN and its fragments and for galactose expression. RESULTS: IgG isolated from GCF contained FN, which was bound to the IgG heavy chains. IgG from GCF of advanced periodontitis patients contained high levels of hypogalactosylated IgG, and bound more FN than IgG from GCF of the other two groups, which contained low levels of this glycoform. FN was in a degraded form in GCF from all studied patients, and a fragment of 48- to 53-kDa molecular mass seemed to be the sole one linked to IgG. CONCLUSIONS: IgG and the FN fragment of 48 to 53 kDa in GCF of periodontitis patients and periodontally healthy subjects are physically connected. This fragment was linked to the heavy chains of IgG and the reaction seemed to be particularly intensive with IgG from advanced periodontitis, which contained significantly less galactose in its sugar chains.

Glycosylation of IgG B cell receptor (IgG BCR) in multiple myeloma: relationship between sialylation and the signal activity of IgG BCR.

Little is known about the glycosylation of the isotype switched B cell receptor (BCR) in multiple myeloma, and the way it might affect receptor function. In this work IgG BCRs isolated from the individual lysates of peripheral blood lymphocytes (PBL) of 32 patients with IgG multiple myeloma and healthy controls were investigated for the expression of sialic acid (SA), galactose (Gal) and N-acetylglucosamine (GlcNAc), the sugars known to specify the glycoforms of human serum IgG. The degree of glycosylation and signaling status of all 32 isolated myeloma IgG BCRs were correlated and compared with the glycosylation of the IgG paraproteins isolated from sera of the same patients. It was shown that BCR IgG in myeloma is more heavily sialylated when compared with normal controls, that the increased sialylation of IgG BCR is associated with higher levels of tyrosine phosphorylation (signaling activity) of the IgG BCR supramolecular complex and that BCR IgG and serum IgG paraprotein from the same patient differed in all cases in the levels of terminal sugar expression. The results suggest that the development of the malignant clone in MM from post-switch B cells expressing IgG BCR at their surfaces to plasma cells secreting IgG paraprotein may be followed by permanent glycosylation changes in the IgG molecules.

Signaling status of IgG B cell receptor (IgG BCR) is indicative for an activated state of circulating B cells in multiple myeloma.

Circulating post-switch B cells have been proposed as proliferative and disseminating progenitors in multiple myeloma. It is unclear whether the class-switched antigen receptor expressed at the surface of these cells plays a role in their expansion. In this work, the signaling status of IgG B cell receptor (BCR) isolated from the lysates of peripheral blood lymphocytes of 32 patients with IgG multiple myeloma, at the time of diagnosis, was investigated by examining whether phosphorylation of BCR Igalpha and Igbeta signal transducer factors (co-receptors) or other signaling molecules was abnormal in these cells when compared with healthy controls. In IgG BCR of normal controls, weak phosphorylation of 56 and 61 kDa Src kinase-related proteins and unphosphorylated co-receptors were found. In myeloma, p56 and p61 kDa proteins, co-receptors, and other IgG BCR-associated proteins from the signal cascade were phosphorylated. Myeloma patients can be classified into subgroups by IgG BCR phosphorylation profiles which characteristically coordinated with the level of IgG paraprotein in serum and the stage of disease. There was a correlative trend between the extent of phosphorylation reduction and advanced stage of disease. Reduced phosphorylation was more pronounced with advanced stages of multiple myeloma.

Hypogalactosylation of salivary and gingival fluid immunoglobulin G in patients with advanced periodontitis.

BACKGROUND: Altered glycosylation of immunoglobulin G (IgG) has been found to affect certain immunological activities of IgG and to correlate with increased inflammation in various disease states. This work deals with the changes in distribution and galactosylation of IgG subclasses present in saliva and gingival crevicular fluid (GCF) of patients with initial and advanced periodontitis and of normal controls. METHODS: IgG subclasses were quantified by dot-blot assay, and the degrees of expression of galactose in the total IgG and its individual subclasses were estimated by lectin immunoblot assay after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separation of IgG and by capture enzyme-linked immunosorbent assay (ELISA), using biotinylated Ricinus communis (RCA-I) and Bandeiraea simplicifolia (BS-II) lectins. RESULTS: The distribution of IgG subclasses in both fluids was found to differ in periodontal patients compared to normal controls. In the periodontitis saliva and GCF, the IgG2 subclass dominated quantitatively, regardless of periodontal status. However, galactose was found to be expressed in IgG heavy chains in normal controls and patients with initial periodontitis but not, or at barely detectable levels, in advanced periodontitis. CONCLUSION: The results suggest that the shift toward hypogalactosylated glycoforms may occur during the process of inflammation of the gingiva.

A longitudinal study of the relationship between galactosylation degree of IgG and rheumatoid factor titer and avidity during long-term immunization of rabbits with BSA.

Although IgG with reduced content of galactose has been implicated as important in the autoimmune rheumatoid factor (RF) response in rheumatoid arthritis (RA), relatively little is known about the temporal relationship between RF and the degree of galactosylation of IgG in vivo. We established an experimental model for studying the dynamic association between changes in the relative extent of galactosylation of IgG antigen(s) and the main parameters of RF activity, such as the titer, specificity and functional affinity/avidity. Rabbits hyperimmunized with BSA were used for examining the influence of long-term antigenic stimulation on the galactosylation status of IgG and rheumatoid factor production. The results showed that the galactosylation profile of IgG varied during the humoral anti-BSA response in rabbits and that the accompanying RF response fluctuated in titer and binding avidity for differently galactosylated IgG. The immune complexes (IC) were found to be composed of differently galactosylated IgG differing in capacity to inhibit the agglutination activity of RF. Moreover, the ability of circulating RF to react avidly with rather small IC was associated with a lower content of galactose in complexed IgG. The results suggest that a certain dynamic relationship exists between the oligosaccharide moiety of IgG and the titer and avidity of RF during the normal anti-BSA response of rabbits.