Disease activity in osteomyelitis: role of radiography

To determine the impact of radiographic findings on the interpretation of bone and gallium scans of patients with active osteomyelitis, the authors reviewed the medical records and radiologic examinations of 104 patients. The only diagnostic finding of active disease on radiographs was the presence of a sequestrum (three patients). Other findings--such as erosion, soft-tissue swelling, and periosteal reaction--proved nonspecific and did not differentiate active from inactive disease. Furthermore, these findings did not significantly change the sensitivity or specificity of the bone and gallium scans, either in detecting or in excluding the presence of active disease.     

Genetic mapping of the copper toxicosis locus in Bedlington terriers to dog chromosome 10, in a region syntenic to human chromosome region 2p13- p16

Abnormal hepatic copper accumulation is recognized as an inherited disorder in man, mouse, rat and dog. The major cause of hepatic copper accumulation in man is a dysfunctional ATP7B gene, causing Wilson disease (WD). Mutations in the ATP7B genes have also been demonstrated in mouse and rat. The ATP7B gene has been excluded in the much rarer human copper overload disease non-Indian childhood cirrhosis, indicating genetic heterogeneity. By investigating the common autosomal recessive copper toxicosis (CT) in Bedlington terriers, we have identified a new locus involved in progressive liver disease. We examined whether the WD gene ATP7B was also causative for CT by investigating the chromosomal co-localization of ATP7B and C04107, using fluorescence in situ hybridization (FISH). C04107 is an anonymous microsatellite marker closely linked to CT. However, BAC clones containing ATP7B and C04107 mapped to the canine chromosome regions CFA22q11 and CFA10q26, respectively, demonstrating that WD cannot be homologous to CT. The copper transport genes CTR1 and CTR2 were also excluded as candidate genes for CT since they both mapped to canine chromosome region CFA11q22. 2-22.5. A transcribed sequence identified from the C04107-containing BAC was found to be homologous to a gene expressed from human chromosome 2p13-p16, a region devoid of any positional candidate genes.      

Ceramide in apoptosis and oxidative stress in allergic inflammation and asthma

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Cell–matrix interactions and dynamic mechanical loading influence chondrocyte gene expression and bioactivity in PEG-RGD hydrogels

The pericellular matrix (PCM) surrounding chondrocytes is thought to play an important role in transmitting biochemical and biomechanical signals to the cells, which regulates many cellular functions including tissue homeostasis. To better understand chondrocytes interactions with their PCM, three-dimensional poly(ethylene glycol) (PEG) hydrogels containing Arg–Gly–Asp (RGD), the cell-adhesion sequence found in fibronectin and which is present in the PCM of cartilage, were employed. RGD was incorporated into PEG hydrogels via tethers at 0.1, 0.4 and 0.8 mM concentrations. Bovine chondrocytes were encapsulated in the hydrogels and subjected to dynamic compressive strains (0.3 Hz, 18% amplitude strain) for 48 h, and their response assessed by cell morphology, ECM gene expression, cell proliferation and matrix synthesis. Incorporation of RGD did not influence cell morphology under free swelling conditions. However, the level of cell deformation upon an applied strain was greater in the presence of RGD. In the absence of dynamic loading, RGD appears to have a negative effect on chondrocyte phenotype, as seen by a 4.7-fold decrease in collagen II/collagen I expressions in 0.8 mM RGD constructs. However, RGD had little effect on early responses of chondrocytes (i.e. cell proliferation and matrix synthesis/deposition). When isolating RGD as a biomechanical cue, cellular response was very different. Chondrocyte phenotype (collagen II/collagen I ratio) and proteoglycan synthesis were enhanced with higher concentrations of RGD. Overall, our findings demonstrate that RGD ligands enhance cartilage-specific gene expression and matrix synthesis, but only when mechanically stimulated, suggesting that cell–matrix interactions mediate chondrocyte response to mechanical stimulation.     

Chronic donor site pain complicating bone graft harvesting from the posterior iliac crest for spinal fusion.

To explore the relationship between surgical approach and chronic posterior iliac crest donor site pain, 151 bone graft harvests with follow-up periods longer than 1 year were evaluated using a detailed questionnaire and follow-up clinical visits. There was no difference in the incidence of chronic donor site pain between harvests performed through the primary midline incision versus a separate lateral oblique incision (28 vs 31%). Twice as many donor sites harvested for reconstructive spinal procedures were reported as having chronic pain as compared with those harvested for spinal trauma, regardless of approach used (39 vs 18%). The association of chronic donor site pain with residual back pain was also greater in the spinal reconstructive group. Thus, it appears that incidence of chronic donor site pain is more dependent on diagnosis than on surgical approach.     

Food aversions and cravings during early pregnancy: association with nausea and vomiting

The prospective cohort study examined whether Ecuadorian women with early pregnancy nausea and vomiting (NVP) are more likely to develop food aversions and cravings, and if so, whether the specific foods identified as aversive or craved are the same as those predicted by the popular maternal-embryo protection hypothesis (MEPH). Consistent with MEPH predictions, women with NVP were more likely to report increased odor sensitivity and aversions for some predicted "toxic" foods and more likely to crave fruits. However, other hypothesis predictions were not supported. The relationship of food aversions and cravings with NVP appears more complicated than that explained by the MEPH.     

Vesicle movement in rat hepatocytes is reduced by ethanol exposure: Alterations in microtubule-based motor enzymes

BACKGROUND & AIMS: Ethanol is known to alter vesicle-mediated protein trafficking in hepatocytes by undefined mechanisms. In this study, the effects of long- and short-term ethanol exposure on vesicle movements were measured in isolated hepatocytes, and alterations in the function of the microtubule-associated motor enzymes dynamin, kinesin, and dynein, which are believed to support the transport and/or budding of vesicles along microtubules, were tested. METHODS: Vesicular movements in isolated hepatocytes exposed to short- and long-term ethanol treatment were measured. Motor adenosine triphosphatase activities and their association with specific membrane organelles were assessed in response to long-term administration of ethanol in vivo or acetaldehyde in vitro. RESULTS: Hepatocytes exposed to short- or long-term ethanol treatment showed a significant reduction in the number of motile vesicles. No alterations in the levels of motor messenger RNA, protein, or enzymatic activity were observed. Interestingly, ethanol had no effect on the association of dynein and kinesin with membranes, whereas there was a significant increase in the amount of dynamin associated specifically with Golgi membranes. CONCLUSIONS: Long- and short-term ethanol exposure markedly reduces hepatocellular vesicle transport by a mechanism apparently independent of any alteration in the enzymatic activity of molecular motors, possibly involving a change in the function of dynamin. (Gastroenterology 1997 Dec;113(6):1938-48)     

Comparison of two Cobas Core enzyme immunoassays with other test systems for the detection of cytomegalovirus-specific IgG and IgM antibodies

The new Cobas Core CMV IGM and IgG enzyme immunoassays (Roche Diagnostic Systems, Basle, Switzerland) were evaluated for their ability to detect cytomegalovirus (CMV)-specific IgM and IgG antibodies. Therefore, both were compared with some other commercially available and already established serological tests used in the laboratory diagnosis of CMV infection. These included the Abbott IMx CMV IgM and IgG assays, the Abbott CMV-M EIA, the Gull CMV IgM and IgG immunofluorescence tests, the medac CMV-IgM-ELA, and the Enzygnost anti-cytomegalovirus assay (Behringwerke). A total of 572 serum samples of various categories were examined and the results showed high concordances between all methods, ranging from 84.5% to 94.9%. In a follow-up on renal transplant patients, the times of first detection of seroconversions were compared. Since a high overall agreement between the Cobas Core CMV IgM and IgG enzyme immunoassays and the other test systems were observed, these new assays represent useful and reliable tools for clinical CMV diagnosis. © 1994 Wiley-Liss, Inc.