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61.
Modic changes following lumbar disc herniation 总被引:4,自引:3,他引:1
Only a small proportion (20%) of patients with LBP can be diagnosed based on a patho-anatomical entity. Therefore, the identification
of relevant subgroups, preferably on a patoanatomical basis, is strongly needed. Modic changes have been described by several
authors as being closely linked with LBP. The aims of this study were to describe the prevalence of Modic changes, their development
as well as their association to LBP, previous disc contour, and surgery in patients with previous severe sciatica. This is
a longitudinal cohort study where the patients were recruited from an RCT comparing two active conservative treatments, the
181 patients, who at baseline had radicular pain in or below the knee; all underwent a physical examination and MRI. MRI’s,
pain history and physical examination of 166 patients were obtained at follow-up 14 months later. The prevalence of Modic
changes type 1 increased from 9% at baseline to 29% at follow-up. At that time, a strong association between Modic changes
and non-specific LBP was noted. Apparently, Modic changes type 1 was more strongly associated with non-specific lumbar pain
than Modic changes type 2. The development of new Modic changes was closely related to the level of a previous disc herniation.
A lumbar disc herniation is a strong risk factor for developing Modic changes (especially type 1) during the following year.
Furthermore, Modic changes are strongly associated with LBP. 相似文献
62.
Liliane Harika Ralph Weissleder Kirtland Poss Claus Zimmer Mikhail I. Papisov Thomas J. Brady 《Magnetic resonance in medicine》1995,33(1):88-92
A model system of a paramagnetic lymphotropic MR contrast agent (Gd-DTPA labeled polyglucose associated macrocomplex, PGM) for T1-weighted MR imaging of lymph nodes in rats and rabbits was evaluated. Pharmacokinetic (tissue accumulation) and MR imaging data (optimal dose and timing parameters) were obtained in normal rats (n = 88) after subcutaneous (SC) injection of paramagnetic, radiolabeled [111In]Gd-DTPA-PGM. A rabbit model of lymph node metastases (n = 8) was ultimately used to demonstrate the potential of MR imaging with Gd-DTPA-PGM for nodal tumor detection. Maximum concentrations of Gd-DTPA-PGM were found in popliteal and paraaortic lymph nodes within 24 h after SC administration, and highest lymph node SNR values were obtained by MR imaging at this time point. The optimum imaging dose was 6–12 μmol Gd/kg. Tumor-lymph node contrast increased from 0.0 ± 1.2 precontrast to 19.2 ± 6.5 (spoiled gradient echo sequence, TR 50/TE 7/flip angle 60°) postcontrast and conspicuity of nodal metastases was improved. Gd-DTPA-PGM accumulates in lymph nodes after SC administration and significantly enhances lymph node signal intensity of normal animals but not metastatic lymph nodes. 相似文献
63.
M Hamoir M Remacle A Youssif D Moulin G Francois D Claus A Kahn Y Frederickx 《Head & neck surgery》1988,10(6):406-410
Parapharyngeal cystic hygroma is a rare tumor of the neck. This report describes two cases in which surgical resection was necessary to overcome sudden airway obstruction and details the surgical technique. These cases were considered "near misses" for sudden infant death syndrome (SIDS) and were revealed by computed tomography (CT) and echography to be parapharyngeal cystic hygroma. The location of this malformation could have produced sudden airway collapse and be erroneously diagnosed as SIDS. The postoperative follow-up was satisfactory and no recurrence was detected. We believe CT and echography should be included in the evaluation of such cases. 相似文献
64.
Allegria Kessous Pierre Colombies Martine Sudries Georges Bourrouillou Jacques Pris Danielle Clement 《Cancer Genetics and Cytogenetics》1980,2(4):335-337
This report describes a new case of chronic myeloid leukemia with an unusual Philadelphia chromosome translocation involving chromosomes No. 4,9, and 22; t(4,9,22) (q31;q34;q11). 相似文献
65.
Mounir Chennaoui Danielle Gomez-Marino Catherine Drogou Cyprien Bourrilhon Samuel Sautivet Charles Yannick Guezennec 《Revue canadienne de physiologie appliquée》2004,29(6):714-730
The aim of this study was to examine hormonal and metabolic changes in a group of 18 professional male cyclists ((.)VO(2)max 69.9 [95 % CI 64.9 to 74.9] mL x kg(-1) x min(-1) ) during two successive periods of adapted intensive training. The second training period included 4 days of cycling competition. Intensity was increased while volume was decreased in the second training. Anthropometric data were collected before and at the end of the two training periods. Venous blood samples were taken in a basal state before the two training sessions and after each training session. Serum concentrations of cortisol (C), testosterone (T), dehydroepiandrosterone sulfate (DHEAs), and catecholamines were determined as well as branched-chain amino acids (valine, leucine, isoleucine) (BCAA) and free fatty acids (FFAs). At the end of the two training periods, the subjects lost fat mass whereas mean body mass was unchanged. The T/C ratio was reduced transiently after the first training session (45.90 %), while DHEAs/C remained unchanged. T/C and DHEAs/C were significantly increased after the second training session compared to the first (48.40 and 97.18 %, respectively). Catecholamines and FFAs were unchanged. The significant increase in BCAA levels after the second training session was of note as it might constitute a "store shape" of amino acids in anticipation of future intense training loads. Based on the responses of testosterone, DHEAs, and cortisol, and on the training-induced increase in BCAA, there appeared to be hormonal and metabolic adaptation despite the inherent psychological stress of competition. 相似文献
66.
Meyer-Fernandes JR Saad-Nehme J Peres-Sampaio CE Belmont-Firpo R Bisaggio DF Do Couto LC Fonseca De Souza AL Lopes AH Souto-Padrón T 《Parasitology research》2004,93(1):41-50
In this work, we describe the ability of living epimastigotes of Trypanosoma cruzi to hydrolyze extracellular ATP. In these intact parasites, there was a low level of ATP hydrolysis in the absence of any divalent metal (2.42±0.31 nmol Pi/h×108 cells). ATP hydrolysis was stimulated by MgCl2, and the Mg-dependent ecto-ATPase activity was 27.15±2.91 nmol Pi/h×108 cells. The addition of MgCl2 to the extracellular medium increased the ecto-ATPase activity in a dose-dependent manner. This stimulatory activity was also observed when MgCl2 was replaced by MnCl2, but not by CaCl2 or SrCl2. The apparent Km for Mg-ATP2– was 0.61 mM, and free Mg2+ did not increase the ecto-ATPase activity. This ecto-ATPase activity was insensitive to the inhibitors of other ATPase and phosphatase activities. To confirm that this Mg-dependent ATPase was an ecto-ATPase, we used an impermeant inhibitor, DIDS (4, 4.diisothiocyanostylbene 2-2-disulfonic acid) as well as suramin, an antagonist of P2 purinoreceptors and inhibitor of some ecto-ATPases. These two reagents inhibited the Mg2+-dependent ATPase activity in a dose-dependent manner. A comparison among the Mg2+-ecto-ATPase activities of the three forms of T. cruzi showed that the noninfective epimastigotes were less efficient at hydrolyzing ATP than the infective trypomastigote and amastigote stages. 相似文献
67.
Upregulation of the Golgi protein GP73 by adenovirus infection requires the E1A CtBP interaction domain 总被引:4,自引:0,他引:4
GP73 is a novel type II Golgi transmembrane protein that is expressed at high levels in the hepatocytes of patients with viral hepatitis (R. D. Kladney, G. A. Bulla, L. Guo, A. L. Mason, A. E. Tollefson, D. J. Simon, Z. Koutoubi, and C. J. Fimmel, 2000, Gene 249, 53-65) and is induced in cultured cells by infection with viruses including adenoviruses. Its biological function and the mechanisms by which its expression may be regulated by viral infection are unknown. Here we report that GP73 is induced at the RNA and protein level in human Hep3B hepatoma cells infected by human Ad5 and Ad2. Hep3B cells were infected with wild-type or mutant adenoviruses. GP73 expression was measured by RNase protection assay, immunoblotting, or immunofluorescence microscopy. GP73 RNA and protein levels were strikingly induced following infection. The rise in GP73 expression coincided with the appearance of the adenovirus E1A and DBP proteins and preceded the expression of the fiber protein, a marker of the late phase of infection. Infection did not affect the expression of giantin, GPP130, or golgin-84, three integral Golgi membrane proteins with structural similarities to GP73. Mapping studies using a panel of mutant adenoviruses demonstrated that the E1A C-terminus, specifically its CtBP interaction domain (CID), is required for GP73 expression. Subsequently, Hep3B cells were transiently transfected with plasmids expressing wild-type or mutant E1A proteins. These studies confirmed that E1A induced GP73 expression via the CID. Our studies establish GP73 as a novel adenovirus-induced cellular protein whose expression is regulated through the CID of the E1A protein. 相似文献
68.
Chlamydiales are important intracellular bacterial pathogens, causing a wide variety of diseases in vertebrates, including humans. Besides the well-known species in the family Chlamydiaceae, new chlamydial organisms have recently been discovered, forming three new families: Parachlamydiaceae, Simkaniaceae and Waddliaceae. Parachlamydia acanthamoebae and Simkania negevensis are currently investigated as emerging human respiratory pathogens. Additional chlamydial lineages have been discovered by 16S rDNA-based molecular studies, and their implication in human infections is poorly known. By using a pan-chlamydia 16S rDNA PCR, we have searched for the presence of chlamydiae in 228 clinical samples that all previously had been shown to be PCR-negative for Chlamydophila pneumoniae: 170 respiratory samples, 45 atheromatic plaques and 13 peripheral blood mononuclear cell samples. Nine respiratory samples tested positive. Sequence analysis has allowed us to assign four sequences to Chlamydophila psittaci, three sequences to Chlamydophila felis, and two sequences to two novel phylotypes belonging to the Parachlamydiaceae. These latter sequences showed similarity values of more than 93% with each other and with the P. acanthamoebae sequence, thus belonging to novel, unrecognized species. In conclusion, this report showed that a variety of non-C. pneumoniae chlamydial respiratory infection is present in humans, and that new parachlamydiae distinct from P. acanthamoebae may be detected in human clinical samples. Future studies will be of interest in order to estimate the diversity of these novel chlamydiae in both clinical and environmental samples, as well as their possible clinical implication in human and animal infections. 相似文献
69.
Carlo Chizzolini Rachel Chicheportiche Danielle Burger Jean-Michel Dayer 《European journal of immunology》1997,27(1):171-177
The role of human T cells in the induction and regulation, upon cell/cell contact, of inflammatory responses by monocytic cells was investigated. The production of interleukin (IL)-1β and IL-1 receptor antagonist (IL-1Ra) by the monocytic THP-1 cell line was measured upon contact with either Th1 or Th2 cell clones. CD4+ T cell clones specific for purified protein derivative of Mycobacterium tuberculosis, predominantly Th1 [high interferon (IFN)-γ and low IL-4 producers], or tetanus toxoid, predominantly Th2 (low IFN-γ and high IL-4 producers), were generated. Cell membranes from antigen-stimulated, but not from resting T cell clones induced dose-dependent cytokine production by THP-1 cells. Th1 clones induced higher levels of IL-1β production (484–806 pg/ml) than did Th2 clones (21–114 pg/ml). In contrast, Th1 clones induced lower levels of IL-1Ra (0.9–7.8 ng/ml) than did Th2 clones (7.0–49.6 ng/ml). Similar results were obtained when T cell clones were activated by cross-linked CD3 and CD28. IL-1β production by THP-1 cells correlated with IFN-γ production by T cell clones but was unaffected by IFN-γ neutralization. IL-1Ra production by THP-1 cells correlated with IL-4 production by T cells and was partially inhibited by IL-4 neutralization. These data indicate that activated Th1 and Th2 cells express different molecules on the cell surface able to induce distinct pro-inflammatory (IL-1β) or anti-inflammatory (IL-1Ra) responses in monocytes. This differential induction of molecules with opposite effects on inflammation stresses the functional heterogeneity in CD4+ T cells. 相似文献
70.
A method is described based on crossed immunoelectrophoresis of a complex antigen mixture in agarose gel followed by incubation of the gel with the monoclonal antibody. The bound monoclonal antibody is detected by the use of a secondary enzyme-labelled antibody.Using this technique we have been able to identify the precipitate arc in crossed immunoelectrophoresis of major histocompatibility complex (MHC) class I molecules in a mixture of all detergent solubilized cell membrane molecules by means of a monoclonal antibody, the specificity of which was known independently to be against MHC class I molecules. In other experiments using the same technique we demonstrated the reaction of a monoclonal antibody specific for chicken Ig light chains. 相似文献