The genome of the social amoeba Dictyostelium discoideum

The social amoebae are exceptional in their ability to alternate between unicellular and multicellular forms. Here we describe the genome of the best-studied member of this group, Dictyostelium discoideum. The gene-dense chromosomes of this organism encode approximately 12,500 predicted proteins, a high proportion of which have long, repetitive amino acid tracts. There are many genes for polyketide synthases and ABC transporters, suggesting an extensive secondary metabolism for producing and exporting small molecules. The genome is rich in complex repeats, one class of which is clustered and may serve as centromeres. Partial copies of the extrachromosomal ribosomal DNA (rDNA) element are found at the ends of each chromosome, suggesting a novel telomere structure and the use of a common mechanism to maintain both the rDNA and chromosomal termini. A proteome-based phylogeny shows that the amoebozoa diverged from the animal-fungal lineage after the plant-animal split, but Dictyostelium seems to have retained more of the diversity of the ancestral genome than have plants, animals or fungi.

Oxidative status during late pregnancy and early lactation in dairy cows

In the last few years, the detection of free radical damage and the body's defences against it have become increasingly important in clinical medicine as a complementary tool in the evaluation of metabolic status. The aim of this study was to evaluate, under field conditions, the anti-oxidant status of healthy cows during late pregnancy and lactation onset using two parameters: (1) plasma levels of malondialdehyde (MDA), a degradation product of lipid peroxidation, and (2) total antioxidant status (TAS). Results were compared with those obtained in another group of cows with lesser metabolic demands. We also investigated possible relationships between antioxidant status markers and other relevant blood parameters. Our results confirmed the characteristic metabolic changes associated with late pregnancy and early lactation. MDA and TAS provided an accurate reflection of the internal physiological status of the animal. The data indicated increased lipid peroxidation around parturition, but with wide individual variations that may be attributable not only to the physiological stage but also to unknown factors that will have to be further considered in future studies.

Identification of the residues in the Myb domain of maize C1 that specify the interaction with the bHLH cofactor R

The maize Myb transcription factor C1 depends on the basic helix-loop-helix (bHLH) proteins R or B for regulatory function, but the closely related Myb protein P does not. We have used the similarity between the Myb domains of C1 and P to identify residues that specify the interaction between the Myb domain of C1 and the N-terminal region of R. Substitution of four predicted solvent-exposed residues in the first helix of the second Myb repeat of P with corresponding residues from C1 is sufficient to confer on P the ability to physically interact with R. However, two additional Myb domain amino acid changes are needed to make the P regulatory activity partially dependent on R in maize cells. Interestingly, when P is altered so that it interacts with R, it can activate the Bz1 promoter, normally regulated by C1 + R but not by P. Together, these findings demonstrate that the change of a few amino acids within highly similar Myb domains can mediate differential interactions with a transcriptional coregulator that plays a central role in the regulatory specificity of C1, and that Myb domains play important roles in combinatorial transcriptional regulation.

Treatment of submassive pulmonary embolism with tenecteplase or placebo: cardiopulmonary outcomes at 3 months: multicenter double-blind, placebo-controlled randomized trial

BACKGROUND

Acute pulmonary embolism (PE) can worsen quality of life due to persistent dyspnea or exercise intolerance.

OBJECTIVE

Test if tenecteplase increases the probability of a favorable composite patient-oriented outcome after submassive PE.

METHODS

Normotensive patients with PE and right ventricular (RV) strain (by echocardiography or biomarkers) were enrolled from eight hospitals. All patients received low-molecular-weight heparin followed by random assignment to either a single weight-based bolus of tenecteplase or placebo, administered in a double-blinded fashion. The primary composite outcome included: (i) death, circulatory shock, intubation or major bleeding within 5 days or (ii) recurrent PE, poor functional capacity (RV dysfunction with either dyspnea at rest or exercise intolerance) or an SF36(®) Physical Component Summary (PCS) score < 30 at 90-day follow-up.

RESULTS

Eighty-three patients were randomized; 40 to tenecteplase and 43 to placebo. The trial was terminated prematurely. Within 5 days, adverse outcomes occurred in three placebo-treated patients (death in one and intubation in two) and one tenecteplase-treated patient (fatal intracranial hemorrhage). At 90 days, adverse outcomes occurred in 13 unique placebo-treated patients and five unique tenecteplase-treated patients Thus, 16 (37%) placebo-treated and six (15%) tenecteplase-treated patients had at least one adverse outcome (exact two-sided P = 0.017).

CONCLUSIONS

Treatment of patients with submassive pulmonary embolism with tenecteplase was associated with increased probability of a favorable composite outcome.

Dexterity enhancement with robotic surgery

BACKGROUND

The aim of this study was to quantify the extent of dexterity enhancement in robotic surgery as compared to laparoscopic surgery.

METHODS

Ten surgeons with varying laparoscopic suturing experience were asked to place three sutures on a suture pad. The sutures were placed laparoscopically, robotically with 2-D vision and robotically with 3-D vision. The da Vinci systems Application Programming Interface (API) was used for positional data. A validated motion analysis system was used for data retrieval for the laparoscopic task. Custom software was developed for data analysis.

RESULTS

Compared to laparoscopic suturing, when the task was undertaken robotically with 2-D vision there was a 20% reduction in the time taken but this was not significant (p = 0.07). There was a 55% reduction in the path traveled by the right hand (p = 0.01) and a 45% reduction in the path traveled by the left hand (p = 0.008). When the task was undertaken robotically with 3-D vision, there was a 40% reduction in the time taken (p = 0.01). There was a 70% reduction in the path traveled by right hand (p = 0.008) and a 55% reduction by the left hand (p = 0.08).

CONCLUSIONS

The presence of wristed instrumentation, tremor abolition, and motion scaling enhance dexterity by nearly 50% as compared to laparoscopic surgery. 3-D vision enhances dexterity by a further 10-15%. In addition, the presence of 3-D vision results in a 93% reduction in skills-based errors.

Event generator tunes obtained from underlying event and multiparton scattering measurements

New sets of parameters ("tunes") for the underlying-event (UE) modelling of the pythia8, pythia6 and herwig++ Monte Carlo event generators are constructed using different parton distribution functions. Combined fits to CMS UE proton-proton ([Formula: see text]) data at [Formula: see text] and to UE proton-antiproton ([Formula: see text]) data from the CDF experiment at lower [Formula: see text], are used to study the UE models and constrain their parameters, providing thereby improved predictions for proton-proton collisions at 13[Formula: see text]. In addition, it is investigated whether the values of the parameters obtained from fits to UE observables are consistent with the values determined from fitting observables sensitive to double-parton scattering processes. Finally, comparisons are presented of the UE tunes to "minimum bias" (MB) events, multijet, and Drell-Yan ([Formula: see text] lepton-antilepton+jets) observables at 7 and 8[Formula: see text], as well as predictions for MB and UE observables at 13[Formula: see text].

Immediate and short-term benefit of multilesion coronary angioplasty: influence of degree of revascularization

The safety and short-term therapeutic benefit of multilesion percutaneous transluminal coronary angioplasty was assessed in 135 patients, 66 of whom had a minimum of 6 months of follow-up study. Primary success, defined as successful dilation of the most critical lesion or all lesions attempted without major in-hospital complications was obtained in 117 (87%) of the 135 patients. Cardiac complications associated with the procedure were uncommon; prolonged angina occurred in 5% and myocardial infarction in 3%; emergency coronary bypass surgery was performed in 4% of the patients. There were no deaths. Complete revascularization was achieved in 46% of the 117 patients with a primary success. Of the 66 patients eligible for 6 month follow-up, 80% had an uncomplicated course and required no further procedures. Clinical improvement by at least one angina functional class was observed in 90% of the patients. Cardiac events such as the need for a second revascularization procedure were significantly more common in patients who had incomplete versus complete revascularization (35 versus 9%; p = 0.018). Repeat coronary angiography performed an average of 5 months after angioplasty revealed restenosis in 18 of 22 symptomatic patients and 3 of 9 asymptomatic patients. Restenosis occurred at the site of a single dilation in 12 patients, at two sites in 8 patients and at three sites in 1 patient. Thus, multilesion coronary angioplasty is an important therapeutic option for selected patients with multivessel disease and can be performed with relatively low risk. Improvement in angina status can be expected even in patients who have incomplete revascularization.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of a novel family of targets of PYK2 related to Drosophila retinal degeneration B (rdgB) protein

The protein tyrosine kinase PYK2 has been implicated in signaling pathways activated by G-protein-coupled receptors, intracellular calcium, and stress signals. Here we describe the molecular cloning and characterization of a novel family of PYK2-binding proteins designated Nirs (PYK2 N-terminal domain-interacting receptors). The three Nir proteins (Nir1, Nir2, and Nir3) bind to the amino-terminal domain of PYK2 via a conserved sequence motif located in the carboxy terminus. The primary structures of Nirs reveal six putative transmembrane domains, a region homologous to phosphatidylinositol (PI) transfer protein, and an acidic domain. The Nir proteins are the human homologues of the Drosophila retinal degeneration B protein (rdgB), a protein implicated in the visual transduction pathway in flies. We demonstrate that Nirs are calcium-binding proteins that exhibit PI transfer activity in vivo. Activation of PYK2 by agents that elevate intracellular calcium or by phorbol ester induce tyrosine phosphorylation of Nirs. Moreover, PYK2 and Nirs exhibit similar expression patterns in several regions of the brain and retina. In addition, PYK2-Nir complexes are detected in lysates prepared from cultured cells or from brain tissues. Finally, the Nir1-encoding gene is located at human chromosome 17p13.1, in proximity to a locus responsible for several human retinal diseases. We propose that the Nir and rdgB proteins represent a new family of evolutionarily conserved PYK2-binding proteins that play a role in the control of calcium and phosphoinositide metabolism downstream of G-protein-coupled receptors.

Effect of lameness on the calving-to-conception interval in dairy cows

OBJECTIVE

To examine the relationship between lameness and the duration of the interval from calving to subsequent conception in lactating dairy cows.

DESIGN

Cohort study.

ANIMALS

837 dairy cows.

PROCEDURE

Cows affected with lameness were classified into 1 of 4 groups on the basis of types of disease or lesions observed, including foot rot, papillomatous digital dermatitis, claw lesions, or multiple lesions. Cows not affected with lameness were classified as healthy. Time from calving to conception was compared between lame cows and healthy cows.

RESULTS

254 (30%) cows were affected with lameness during lactation. Most lame cows (59%) had claw lesions. Lame cows with claw lesions were 0.52 times as likely to conceive as healthy cows. Median time to conception was 40 days longer in lame cows with claw lesions, compared with healthy cows. Number of breedings per conception for lame cows with claw lesions was significantly higher than that for healthy cows.

CONCLUSION AND CLINICAL RELEVANCE

Claw lesions were the most important cause of lameness, impairing reproductive performance in dairy cows, as indicated by a higher incidence of affected cows and a greater time from calving to conception and a higher number of breedings required per conception, compared with healthy cows.

Multiple facets of junD gene expression are atypical among AP-1 family members

JunD is a versatile AP-1 transcription factor that can activate or repress a diverse collection of target genes. Precise control of junD expression and JunD protein-protein interactions modulate tumor angiogenesis, cellular differentiation, proliferation and apoptosis. Molecular and clinical knowledge of two decades has revealed that precise JunD activity is elaborated by interrelated layers of constitutive transcriptional control, complex post-transcriptional regulation and a collection of post-translational modifications and protein-protein interactions. The stakes are high, as inappropriate JunD activity contributes to neoplastic, metabolic and viral diseases. This article deconvolutes multiple layers of control that safeguard junD gene expression and functional activity. The activity of JunD in transcriptional activation and repression is integrated into a regulatory network by which JunD exerts a pivotal role in cellular growth control. Our discussion of the JunD regulatory network integrates important open issues and posits new therapeutic targets for the neoplastic, metabolic and viral diseases associated with JunD/AP-1 expression.

Regular exercise enhances insulin activation of IRS-1-associated PI3-kinase in human skeletal muscle

Insulin action in skeletal muscle is enhanced by regular exercise. Whether insulin signaling in human skeletal muscle is affected by habitual exercise is not well understood. Phosphatidylinositol 3-kinase (PI3-kinase) activation is an important step in the insulin-signaling pathway and appears to regulate glucose metabolism via GLUT-4 translocation in skeletal muscle. To examine the effects of regular exercise on PI3-kinase activation, 2-h hyperinsulinemic (40 mU. m(-2). min(-1))-euglycemic (5.0 mM) clamps were performed on eight healthy exercise-trained [24 +/- 1 yr, 71.8 +/- 2.0 kg, maximal O(2) uptake (VO(2 max)) of 56.1 +/- 2.5 ml. kg(-1). min(-1)] and eight healthy sedentary men and women (24 +/- 1 yr, 64.7 +/- 4.4 kg, VO(2 max) of 44.4 +/- 2.7 ml. kg(-1). min(-1)). A [6, 6-(2)H]glucose tracer was used to measure hepatic glucose output. A muscle biopsy was obtained from the vastus lateralis muscle at basal and at 2 h of hyperinsulinemia to measure insulin receptor substrate-1(IRS-1)-associated PI3-kinase activation. Insulin concentrations during hyperinsulinemia were similar for both groups (293 +/- 22 and 311 +/- 22 pM for trained and sedentary, respectively). Insulin-mediated glucose disposal rates (GDR) were greater (P < 0.05) in the exercise-trained compared with the sedentary control group (9.22 +/- 0.95 vs. 6.36 +/- 0.57 mg. kg fat-free mass(-1). min(-1)). Insulin-stimulated PI3-kinase activation was also greater (P < 0.004) in the trained compared with the sedentary group (3.8 +/- 0.5- vs. 1.8 +/- 0.2-fold increase from basal). Endurance capacity (VO(2 max)) was positively correlated with PI3-kinase activation (r = 0.53, P < 0.04). There was no correlation between PI3-kinase and muscle morphology. However, increases in GDR were positively related to PI3-kinase activation (r = 0.60, P < 0.02). We conclude that regular exercise leads to greater insulin-stimulated IRS-1-associated PI3-kinase activation in human skeletal muscle, thus facilitating enhanced insulin-mediated glucose uptake.

6q deletion in Waldenström macroglobulinemia is associated with features of adverse prognosis

Fluorescence in situ hybridisation (FISH) is an effective technique for the cytogenetic analysis of Waldenström macroglobulinemia (WM), but the potential impact of molecular cytogenetics on disease evolution and as a prognostic marker is still unknown. Deletion of the long arm of chromosome 6 (6q-) is the most frequent cytogenetic abnormality in WM. This study analysed the prevalence of this aberration in 102 WM patients, and correlated it with disease characteristics. The incidence of 6q21 deletion was 7% by conventional cytogenetics and 34% when analysed by FISH (54% when cytoplasmic immunoglobulin M-FISH was used). Patients with deletion of 6q displayed features of adverse prognosis, such as higher levels of beta2-microglobulin and monoclonal paraprotein and a greater tendency to display anaemia and hypoalbuminemia. Interestingly, there was a correlation between the presence of 6q deletion and the International Staging System prognostic index (incidence of 6q- among patients stratified in stages 1, 2 and 3 was 24%, 42% and 67% respectively). Those patients diagnosed with smouldering WM who displayed the abnormality showed a trend to an earlier requirement of treatment. Finally, the survival analysis did not show differences between the two groups of patients, probably due to the short follow up of our series.

Lack of Borrelia burgdorferi DNA in synovial samples from patients with antibiotic treatment-resistant Lyme arthritis

OBJECTIVE

To determine whether Borrelia burgdorferi DNA may be detected in synovial tissue from patients with Lyme arthritis who have persistent synovial inflammation after antibiotic treatment.

METHODS

Synovial specimens obtained at synovectomy from 26 patients with antibiotic treatment-resistant Lyme arthritis and from 10 control subjects were tested for B burgdorferi DNA using 3 primer-probe sets that target genes encoding outer surface proteins A or B or a flagellar protein (P41) of the spirochete.

RESULTS

The 26 patients with Lyme arthritis, who had received antibiotic therapy for a mean total duration of 8 weeks prior to synovectomy, and the 10 control subjects each had negative polymerase chain reaction (PCR) results in synovial samples. When the samples were spiked with approximately 1-10 B burgdorferi, all but 1 had positive PCR results, suggesting that spirochetal DNA could have been detected in most of the unspiked samples if it had been present.

CONCLUSION

These results indicate that synovial inflammation may persist in some patients with Lyme arthritis after the apparent eradication of the spirochete from the joint with antibiotic therapy.

Adaptor function for the Syk kinases-interacting protein 3BP2 in IL-2 gene activation

Syk-family tyrosine kinases are essential for lymphocyte development and activation. Using a yeast two-hybrid screen to identify Syk kinases-interacting proteins (SKIPs), we isolated 3BP2, an Abl SH3-interacting protein of unknown function. 3BP2 was selectively expressed in hematopoietic/lymphoid tissues and bound via its SH2 domain activated Syk-family kinases in mammalian cells, including in antigen receptor-stimulated T cells. In addition to Zap-70, the 3BP2 SH2 domain associated in vitro with LAT, Grb2, PLCgamma1, and Cbl from activated T cell lysates. Transient 3BP2 overexpression induced transcriptional activation of the IL-2 promoter and its NFAT or AP-1 elements. This activity was dependent on the SH2 and pleckstrin-homology domains of 3BP2, and required functional Syk kinases, Ras, and calcineurin. Thus, 3BP2 is an important adaptor that may couple activated Zap-70/Syk to a LAT-containing signaling complex involved in TCR-mediated gene transcription.

Reduction of the diagnostic window with a new combined p24 antigen and human immunodeficiency virus antibody screening assay

In order to reduce the window phase between time of human immunodeficiency virus (HIV) infection and laboratory diagnosis, new fourth generation screening assays which permit a simultaneous detection of HIV antigen and antibody have been developed. In a multicenter study, a new automated fourth generation assay, Enzymun-Test HIV Combi (Boehringer Mannheim GmbH) was compared to third generation assay, p24 antigen tests and Western blot. A total of 37 seroconversion panels, samples of the early infection (n = 42), HIV-1 antibody positive sera, including subtypes A E, and O (n = 1118), HIV-2 positive samples (n = 252) and cell culture supernatants infected with different HIV-1 subtypes and HIV-2 (n = 50), blood donors (n = 6649), hospitalized patients (n = 475), HIV neg. sera with indeterminate Western blot (n = 32), potentially cross reactive serum samples (n = 435) and HIV negative specimens from Cameroon (n = 68) were tested. A total of 16 of 29 seroconversions were detected on average 8.5 days earlier with Enzymun-Test HIV Combi than HIV-1/HIV-2 3rd generation EIA (Abbott Laboratories). Overall, in the 29 panels investigated comparatively with the two assays, the mean time delay between Enzymun-Test HIV Combi and HIV-1/HIV-2 3rd generation EIA was 4.7 days. HIV antigen was detected in three out of 35 seroconversions one bleed earlier with HIV-1 Ag Monoclonal than with Enzymun-Test HIV Combi. Enzymun-Test HIV Combi showed a sensitivity of 100% for HIV antibody detection for HIV-1 group M and O and HIV-2 positive specimens. While p24 antigen of different HIV-1 subtypes was detected with Enzymun-Test HIV Combi in all the 49 cell culture supernatants, HIV Ag was not detected in an HIV-2 virus lysate. A total of 66 false positive results out of 7659 HIV negative samples were obtained with the Enzymun-Test HIV Combi. The specificity for unselected blood donors was 99.6%. The Enzymun-Test HIV Combi permits an earlier diagnosis of HIV infection than third generation assays through the detection of p24 antigen, which may be present in serum samples from individuals with recent HIV infection prior to seroconversion and it shows an excellent sensitivity for antibodies to all known HIV-1 subtypes and HIV-2. The specificity in blood donors and hospitalized patients is comparable to that of other assays.

Race-start characteristics and risk of catastrophic musculoskeletal injury in Thoroughbred racehorses

OBJECTIVE

To identify race-start characteristics associated with catastrophic musculoskeletal (MS) injury in Thoroughbred racehorses at 2 racetracks in Florida during 1995 through 1998.

DESIGN

Matched case-control study.

ANIMALS

97 Thoroughbreds (case horses) that incurred a catastrophic MS injury during racing and 388 Thoroughbreds (control horses) randomly selected from noninjured participants and matched on the basis of racetrack and year.

PROCEDURE

Incidence of MS injury was calculated for all race meets at 2 racetracks in Florida from 1995 through 1998. Race-start characteristics were compared among case and control horses, using conditional logistic regression.

RESULTS

Overall incidence of MS injury was 1.2/1,000 race starts (97/79,416 starts). Incidence of injury was significantly higher for turf races (2.3/1,000 starts) than for dirt races (0.9/1,000 starts). Sex, number of days since last race, and racing surface were associated with risk of injury; geldings, > or = 33 days since the last race, and turf racing surface were associated with a higher risk of injury.

CONCLUSIONS AND CLINICAL RELEVANCE

Incidence of injury among Thoroughbreds in Florida was associated with sex, number of days since last race, and racing surface. Days since last race may have been an indicator of previous health and lameness problems. Racing surface may have been a risk factor for MS injury because turf races tended to be more competitive than dirt races. Horses running in turf races were more likely to participate in races with a large field, handicap races, long races, and races with high purses.

High-sensitive immunophenotyping and DNA ploidy studies for the investigation of minimal residual disease in multiple myeloma

Sensitive techniques for monitoring minimal residual disease (MRD) in multiple myeloma (MM) are needed to evaluate the effectiveness of new intensive treatment strategies. The aim of the present study was to explore the applicability and sensitivity of flow cytometry immunophenotyping and DNA ploidy studies for the investigation of residual myelomatous plasma cells (PC) in MM patients. Bone marrow (BM) samples from 61 untreated MM patients were immunophenotypically analysed with a panel of 21 monoclonal antibodies, using a high-sensitive method based on a two-step acquisition procedure through a SSC/CD38 -CD138+ 'live-gate'. Overall, in 87% of MM cases, PC displayed an aberrant phenotype at diagnosis. The most important aberrant criteria were: antigen over-expression of CD56 (62%), CD28 (16%) and CD33 (6%) and asynchronous expression of CD117 (28%), sIg (21%) and CD20 (10%). DNA aneuploidy was found in 62% of cases. The simultaneous use of these two techniques allowed the detection of aberrant/aneuploid PC in 95% of the cases. Based on dilutional experiments, the detection limit of both techniques ranged from 10(-4) to 10(-5). In 29 stem cells harvests and 19 BM samples obtained 3 months after autologous transplantation, we have investigated the presence of residual myelomatous PC; they were detected in 44% of the stem cell collections and in 61% of the BM samples obtained after transplant. The percentage of pathological PC did not significantly change during the days of harvest. In summary, the present study shows that the combined use of immunophenotyping and DNA ploidy studies is a suitable approach for MRD investigation in MM patients based on their applicability (95% of cases) and sensitivity (up to 10(-5)).

Antibacterial and free-radical scavenging activities of Sonoran propolis

AIMS

To evaluate the antibacterial and free-radical scavenging (FRS) activities of propolis collected from three different areas of Sonoran Desert in northwestern Mexico [Pueblo de Alamos (PAP), Ures (UP) and Caborca (CP)].

METHODS AND RESULTS

The antibacterial and FRS activities of Sonoran propolis were determined by the broth microdilution method and the DPPH (1,1-diphenyl-2-picrylhydracyl) assay, respectively. Propolis samples had antibacterial activity against only Gram-positive bacteria. The UP sample showed the highest antibacterial activity against Staphylococcus aureus [minimal inhibitory concentration (MIC) 100 microg ml(-1)] in a concentration-dependent manner (UP > CP > PAP). Caffeic acid phenethyl ester (CAPE), a UP propolis constituent, had very high growth-inhibitory activity towards Gram-positive bacteria, particularly against S. aureus (MIC 0.1 mmol l(-1)). To our knowledge, this is the first study showing a strong antibacterial activity of CAPE against S. aureus. Additionally, propolis CP exhibited high FRS activity (86% +/- 0.3 at 100 microg ml(-1)) comparable with those of the reference antioxidants vitamin C (87.4% +/- 1.7 at 70 micromol l(-1)) and BHT (66.07% +/- 0.76 at 140 micromol l(-1)). The propolis compounds CAPE and rutin showed high FRS activity (90.4% +/- 0.2 and 88.5% +/- 0.8 at 70 micromol l(-1), respectively).

CONCLUSIONS

Sonoran propolis UP and CAPE had strong antibacterial activity against S. aureus. In addition, propolis CP showed potent FRS activity comparable with those of vitamin C and BHT.

SIGNIFICANCE AND IMPACT OF THE STUDY

The strong antibacterial and antioxidant properties of Sonoran propolis and some of its constituents support further studies on the clinical applications of this natural bee product against S. aureus and several oxidative damage-related diseases.

Human cytomegalovirus elevates levels of the cellular protein p53 in infected fibroblasts

Human cytomegalovirus (HCMV), like other DNA tumor viruses, induces morphological transformation of cells in vitro and stimulates host cell macromolecular synthesis in infected cells. Since other DNA tumor viruses, such as simian virus 40 and adenovirus, have previously been shown to interact with cellular protein p53, we investigated whether infection of cells by HCMV would modulate cellular p53 levels. Our results indicate that HCMV elevates cellular p53 levels on the order of 10- to 20-fold in infected fibroblasts. The induction of elevated p53 levels was dependent upon the presence of active virus and was prevented by neutralizing antibody. The induction of elevated p53 levels was determined not to be due to virus-receptor interactions or HCMV late events. The induction of elevated p53 levels commenced at immediate-early times of the HCMV multiplication cycle (6 h postinfection) and reached maximal levels by 24 h postinfection, before most of the HCMV DNA synthesis was initiated. HCMV immediate-early proteins were clearly shown to be responsible for elevating p53 levels in infected fibroblasts; expression of HCMV immediate-early region 1 and 2 proteins resulted in elevation of p53 levels in transfected human fibroblasts. This is the first report of increased p53 levels caused by HCMV in infected fibroblasts.

The sequence alteration associated with a mutational hotspot in p53 protects cells from lysis by cytotoxic T lymphocytes specific for a flanking peptide epitope

A high proportion of tumors arise due to mutation of the p53 tumor suppressor protein. A p53 hotspot mutation at amino acid position 273 from R to H, flanking a peptide epitope that spans residues 264-272, renders cells resistant to killing by human histocompatibility leukocyte antigen (HLA)-A*0201-restricted cytotoxic T lymphocytes (CTLs) specific for this epitope. Acquisition of the R to H mutation at residue 273 of the human p53 protein promotes tumor growth in vivo by selective escape from recognition by p53.264-272 peptide-specific CTLs. Synthetic 27-mer p53 polypeptides covering the antigenic nonamer region 264-272 of p53 were used as proteasome substrates to investigate whether the R to H mutation at the P1' position of the COOH terminus of the epitope affects proteasome-mediated processing of the protein. Analysis of the generated products by tandem mass spectrometry and the kinetics of polypeptide processing in conjunction with CTL assays demonstrate that the R to H mutation alters proteasomal processing of the p53 protein by inhibiting proteolytic cleavage between residues 272 and 273. This prevents the release of the natural CTL epitope that spans flanking residues 264-272 as well as a putative precursor peptide. These results demonstrate that mutation of p53 not only leads to malignant transformation but may also, in some instances, affect immune surveillance and should be considered in the design of cancer vaccines.

Frequency domain models of the EEG

The structure of the normal resting EEG crosspectrum SVV(omega) is analyzed using complex multivariate statistics. Exploratory data analysis with Principal Component Analysis (PCA) is followed by hypothesis testing and computer simulations related to possible neural generators. The SVV(omega) of 211 normal individuals (ages 5 to 97) may be decomposed into two types of processes: the xi process with spatial isotropicity reflecting diffuse, correlated cortical generators with radial symmetry, and processes that seem to be generated by more spatially concentrated, correlated sources. The latter are reflected as spectral peaks such as the process. The eigenvectors of the xi process are the Spherical Harmonic Functions which explains the recurring pattern of maps characteristic of the spatial PCA of qEEG data. A new method for estimating sources in the frequency domain which fits dipoles to the whole crosspectrum is applied to explain the characteristics of the localized sources.

Extraction and validation of a new set of CMS pythia8 tunes from underlying-event measurements

New sets of CMS underlying-event parameters ("tunes") are presented for the pythia8 event generator. These tunes use the NNPDF3.1 parton distribution functions (PDFs) at leading (LO), next-to-leading (NLO), or next-to-next-to-leading (NNLO) orders in perturbative quantum chromodynamics, and the strong coupling evolution at LO or NLO. Measurements of charged-particle multiplicity and transverse momentum densities at various hadron collision energies are fit simultaneously to determine the parameters of the tunes. Comparisons of the predictions of the new tunes are provided for observables sensitive to the event shapes at LEP, global underlying event, soft multiparton interactions, and double-parton scattering contributions. In addition, comparisons are made for observables measured in various specific processes, such as multijet, Drell-Yan, and top quark-antiquark pair production including jet substructure observables. The simulation of the underlying event provided by the new tunes is interfaced to a higher-order matrix-element calculation. For the first time, predictions from pythia8 obtained with tunes based on NLO or NNLO PDFs are shown to reliably describe minimum-bias and underlying-event data with a similar level of agreement to predictions from tunes using LO PDF sets.