Sil overexpression in lung cancer characterizes tumors with increased mitotic activity

Sil (SCL interrupting locus) was cloned from the most common chromosomal rearrangement in T-cell acute lymphoblastic leukemia. It is an immediate early gene whose expression is associated with cell proliferation. Sil protein levels are tightly regulated during the cell cycle, reaching peak levels in mitosis and disappearing on transition to G1. A recent study found Sil to be one of 17 genes whose overexpression in primary adenocarcinomas predicts metastatic spread. We hypothesized that Sil might have a role in carcinogenesis. To address this question, we utilized several approaches. Using a multitumor tissue array, we found that Sil protein expression was increased mostly in lung cancer, but also at lower levels, in a subset of other tumors. Microarray gene expression analysis and immunohistochemistry of lung cancer samples verified these observations. Sil gene expression in lung cancer correlated with the expression of several kinetochore check-point genes and with the histopathologic mitotic index. These observations suggest that overexpression of the Sil gene characterizes tumors with increased mitotic activity.     

Associations between measles antibody levels and the protein structure of class II human leukocyte antigens

In this study, we describe associations between variation in human leukocyte antigen (HLA) DP and DQ amino acid sequences and low measles antibody levels after measles immunization. We tested serum samples from 242 children for measles immunoglobulin G antibodies. We performed class II HLA typing and examined associations between DQ and DP exon 2 amino acid sequences and antibody levels. No DP amino acid variants were associated with seronegativity. However, 11 DQA and 6 DQB amino acid variants were associated with seronegativity (p<0.005). These amino acid variants were highly correlated, and the significant DQA amino acids were only found in alleles *0201, *0301, *0401, *0501, and *0601. Two of the amino acids associated with measles seronegativity were located in predicted binding pockets of the DQ molecule; one was present in the leader sequence. Among the DQB alleles, all of the amino acid variants associated with seronegativity were present only in the DQB*0201 allele. Two of the amino acids associated with seronegativity were located in predicted binding pockets of the DQ molecule; two were located in the leader sequence. Our data suggest that specific DQA and DQB amino acid variations are associated with measles seronegativity after vaccination.     

Effect of fetal number on maternal serum uric acid concentration

The aim of this study was to examine whether maternal serum uric acid (UA) concentrations are influenced by the number of fetuses and whether this effect is confounded by maternal body mass index (BMI). Medical records of 207 consecutive twin and 69 triplet pregnancies admitted to our high-risk pregnancy unit between 1994 and 1998 were reviewed. Pregnancies complicated by acute or chronic renal diseases, vascular diseases, hypertension, hemolysis, diabetes mellitus, or proteinuria were excluded. The remaining 137 twin and 42 triplet pregnancies were matched with 118 consecutive singleton pregnancies who met the same exclusion criteria and were admitted in the first half of 1998. Each birth order study group was further stratified and compared within three maternal BMI subgroups. Serum UA concentrations were higher in twin and triplet pregnancies compared to singletons (4.6 +/- 1.3, 5.2 +/- 1.2, and 3.8 +/- 0.7 mg%, respectively; p <0.01). These differences in UA concentration persisted after grouping by BMI classes. Serum UA concentration in pregnancy are positively correlated with the number of fetuses. For clinical purpose, the UA cutoff concentration should be adjusted using mean + 2 SD as follows: 5.2, 7.2, and 7.6 for singleton, twin, and triplets, respectively.     

Patients with prior second-trimester loss: prophylactic cerclage or serial transvaginal sonograms?

OBJECTIVE: To compare management with prophylactic cerclage versus serial transvaginal sonograms of the cervix in patients with prior second-trimester loss. STUDY DESIGN: Singleton pregnancies with prior second-trimester spontaneous loss between 14 and 24 weeks' gestation were retrospectively reviewed. At the obstetricians' discretion, some were managed with prophylactic cerclage and some with serial transvaginal sonograms of the cervix, starting at 14 weeks, and cerclage only if cervical length was <25 mm or funneling was >25% before 24 weeks. All cerclages were McDonald. Primary outcome was preterm delivery at <35 weeks. RESULTS: Of 177 patients with singleton pregnancies who had prior second-trimester loss identified, 66 received prophylactic cerclage and 111 were followed up with transvaginal sonography, of which 36% (40/111) had therapeutic cerclage because of cervical changes. The two management groups of prophylactic cerclage versus transvaginal sonography of the cervix did not differ in any measure of obstetric outcome, including preterm delivery at <35 weeks (23% vs 30%; P =.3), preterm delivery at <33 weeks (21% vs 26%; P =.5), or gestational age at delivery (34.6 +/- 6.8 weeks vs 34.4 +/- 6.8 weeks; P =.8). CONCLUSION: In patients with prior second-trimester loss, serial transvaginal sonography of the cervix, with cerclage only if indicated by cervical changes, is a valuable alternative to a policy of uniform prophylactic cerclage.     

Tumor necrosis factor as a mediator of cardiac toxicity following snake envenomation

OBJECTIVE: To investigate the possible role of tumor necrosis factor in mediating cardiotoxicity following venom injection in a rat. DESIGN: A randomized controlled experimental study using a Langendorff isolated heart model. SETTING: Animal laboratory. SUBJECTS: Adult male Wistar rats. INTERVENTIONS: The control group (n = 10) was injected with saline only. Each animal in the experimental groups 1-3 (n = 10 each) was injected with Vipera aspis venom 500 microg/kg intramuscularly. Group 1 animals received no additional substance beforehand, group 2 animals were injected intramuscularly with 250 microg of soluble tumor necrosis factor receptor (sTNF-R p55) 15 mins before the venom injection, and group 3 animals were injected intraperitoneally with 40 microg of anti-tumor necrosis factor 60 mins before the venom injection. MEASUREMENTS AND MAIN RESULTS: Cardiac performances were investigated following envenomation. Cardiac histology and myocardial tumor necrosis factor-RNA concentrations were assessed. Serum tumor necrosis factor concentrations rose and peaked 2 hrs following envenomation. A reduction in peak systolic pressures, maximum and minimum change in pressure over time, time-pressure integral, and coronary flow occurred in the venom-only-injected rats compared with controls, whereas blocking tumor necrosis factor activity prevented the deleterious cardiac effects of the envenomation. No histologic changes or increases in myocardial tumor necrosis factor-RNA concentrations were detected. CONCLUSION: These results strongly suggest that systemic release of tumor necrosis factor mediates cardiac toxicity following Vipera aspis envenomation.     

Expression of Dp260 in muscle tethers the actin cytoskeleton to the dystrophin-glycoprotein complex and partially prevents dystrophy

Dystrophin forms a mechanical link between the actin cytoskeleton and the extracellular matrix in muscle that helps maintain sarcolemmal integrity. Two regions of dystrophin have been shown to bind actin: the N-terminal domain and rod domain repeats 11-17. To better understand the roles of these two domains and whether the rod domain actin-binding domain alone can support a mechanically functional link with actin, we constructed transgenic mice expressing Dp260 in skeletal muscle. Dp260, the retinal isoform of dystrophin, lacks the N-terminal domain and a significant portion of the rod domain, but retains the rod domain actin-binding domain. Our results indicate that Dp260 expression restores a stable association between costameric actin and the sarcolemma, assembles the dystrophin-glycoprotein complex, and significantly slows the progression of the dystrophy in the dystrophin-deficient mdx mouse. We assessed the functional integrity of the mechanical link in Dp260 transgenic mdx mice and found that Dp260 muscles showed normal resistance to contraction-induced injury, but dramatic reductions in force generation similar to those found with mdx muscles. Morphologically, Dp260 muscles displayed reduced amounts of inflammation and fibrosis, but still showed a significant, albeit reduced, amount of degeneration/regeneration. These data demonstrate that protection from contraction-induced injury can dramatically ameliorate, but not completely halt, the dystrophic process. We suggest that a non-mechanical defect, attributed to the loss of the N terminus of dystrophin, is likely responsible for the residual dystrophy observed.     

Homogeneous assays for cellular protein degradation using beta-galactosidase complementation: NF-kappaB/IkappaB pathway signaling

Activation of cells by the tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) cytokines results in activation of the nuclear factor-kappaB (NF-kappaB) via proteasomal degradation of an associated IkappaB molecule. To monitor cellular IkappaB, the protein was recombinantly expressed as a fusion protein with a novel enzymatic tag, ProLabel (PL). ProLabel is a small 5.5-kDa sequence from the amino-terminal amino acids of beta-galactosidase, possesses a simple ribbon structure, and can be fused to many proteins via the amino or carboxyl terminus. Expression of this construct allows quantitative detection of the recombinant protein in crude lysates by using a method based on beta-galactosidase enzyme fragment complementation (EFC). Transient transfection of IkappaB-PL in HeLa cells generated an EFC signal that was highly correlated with a western analysis of the protein construct. ProLabel expressed alone in the cells did not show any EFC activity, due to rapid proteolytic degradation, indicating a very low background signal from the protein tag. TNF-alpha and IL-1 treatment induced a concentration-dependent degradation of IkappaB-PL, with potency values similar to those reported using other methods. IkappaBM-PL (mutant of IkappaB-PL), in contrast, did not undergo degradation for concentrations up to and including 10 ng/ml TNF-alpha or IL-1, demonstrating that degradation of IkappaB-PL was specific to the NF-kappaB pathway activation. TNF-alpha and IL-1 induced maximal IkappaB-PL degradation within 30 min of induction. This was reversed by several agents that ablate this pathway, including anti-TNF-alpha antibodies and the proteasome inhibitor, MG-132. The assay was amenable to HTS systems, with good precision and reproducibility. Z' values and coefficients of variance for IkappaB-PL degradation were 0.6 and <9%, respectively.     

Scintigraphic monitoring of mucociliary tracheo-bronchial clearance of technetium-99m macroaggregated albumin aerosol

A simple method for in vivo monitoring mucociliary tracheo-bronchial clearance is described. Eighteen healthy subjects and 13 patients with various chronic lung diseases were studied by this method. The principle of using an aerosol administration system similar to the system used for routine ventilation lung studies is stressed. Proximal large airway deposition of the radioaerosol was obtained by using relatively large particles (average diameter 2 microM) of [99mTc]MAA aerosol. Monitoring was performed by visual inspection of the tracheo-bronchial cinescintigraphic ascendence of the accumulated radioactive boli and by assessing their rate of clearance via automated computer analysis of the time-activity curves, following the movement of each bolus. The normal mean +/- s.d. clearance rate thus obtained was 4.7 +/- 1.3 mm/min. This rate appears to be more precise as compared with the range of results obtained by other radioisotopic methods. Significantly faster rates, mean 8.2 +/- 1.4 mm/min (p less than 0.001) were obtained in bronchiectatic patients while slower rates (2.8 mm/min) were seen in a patient with ciliary dyskinesia.     

Transfer of Carbapenem-Resistant Plasmid from Klebsiella pneumoniae ST258 to Escherichia coli in Patient

Klebsiella pneumoniae carbapenemase (KPC) 3–producing Escherichia coli was isolated from a carrier of KPC-3–producing K. pneumoniae. The KPC-3 plasmid was identical in isolates of both species. The patient''s gut flora contained a carbapenem-susceptible E. coli strain isogenic with the KPC-3–producing isolate, which suggests horizontal interspecies plasmid transfer.