Safety, complications and clinical outcome after ultrasound-guided paravertebral catheter insertion for rib fracture analgesia: a single-centre retrospective observational study.

Rib fractures are associated with significant morbidity and mortality. Ultrasound-guided thoracic paravertebral catheter insertion has been described for the management of pain secondary to rib fractures. We conducted a retrospective observational study of all patients with rib fractures who had a paravertebral catheter inserted for analgesia provision over a 4-year period. Data from the Trauma Audit and Research Network were used to compare patients with rib fractures who were managed with paravertebral catheters to those managed with systemic analgesia. A total of 314 consecutive paravertebral catheters were inserted in 290 patients. Five (1.9%) catheters were removed due to ineffective analgesia. Other minor complications occurred in three cases (0.96%). The proportion of rib fracture patients managed with paravertebral catheters increased from 31/200 (15.5%) in the first year of study to 81/168 (48.2%) in the fourth; over this time-period the observed:predicted mortality ratio fell from 1.04 to 0.66. Proportional hazard regression with and without propensity score matching demonstrated a reduction in mortality associated with paravertebral catheter use, but this became statistically non-significant when time-dependent analysis was used. Paravertebral catheters are a safe and effective technique for rib fracture analgesia; however, our data were insufficient to demonstrate any improvement in mortality.

Aberrant expression and biological significance of Sox2, an embryonic stem cell transcriptional factor, in ALK-positive anaplastic large cell lymphoma.

Sox2 (sex-determining region Y-Box) is one of the master transcriptional factors that are important in maintaining the pluripotency of embryonic stem cells (ESCs). In line with this function, Sox2 expression is largely restricted to ESCs and somatic stem cells. We report that Sox2 is expressed in cell lines and tumor samples derived from ALK-positive anaplastic large cell lymphoma (ALK(+)ALCL), for which the normal cellular counterpart is believed to be mature T-cells. The expression of Sox2 in ALK(+)ALCL can be attributed to nucleophosmin-anaplastic lymphoma kinase (NPM-ALK), the oncogenic fusion protein carrying a central pathogenetic role in these tumors. By confocal microscopy, Sox2 protein was detectable in virtually all cells in ALK(+)ALCL cell lines. However, the transcriptional activity of Sox2, as assessed using a Sox2-responsive reporter construct, was detectable only in a small proportion of cells. Importantly, downregulation of Sox2 using short interfering RNA in isolated Sox2(active) cells, but not Sox2(inactive) cells, resulted in a significant decrease in cell growth, invasiveness and tumorigenicity. To conclude, ALK(+)ALCL represents the first example of a hematologic malignancy that aberrantly expresses Sox2, which represents a novel mechanism by which NPM-ALK mediates tumorigenesis. We also found that the transcriptional activity and oncogenic effects of Sox2 can be heterogeneous in cancer cells.

Endothelial progenitor cells - hype or hope?

The discovery of endothelial progenitor cells (EPC) radically altered our views of adult tissue angiogenesis, indicating the contribution of circulating bone marrow-derived cells to new blood vessel formation, rather than migration and replication of local endothelial cells. This opened up the prospect of new ways to repair damaged tissues, using EPC to encourage neoangiogenesis or the re-endothelialization of larger vessels. Within less than 5 years from the description of EPC and the inception of experimental studies, human studies were started with the aim of using autologous bone marrow-derived EPC to enhance tissue function after ischemic vascular injury, particularly after myocardial infarction (MI). However, the clinical studies have shown at best modestly encouraging results. Moreover, subsequent investigation has made it clear that these EPC are not true endothelial progenitors, although they are likely to play a role in angiogenesis by virtue of the release of paracrine angiogenic factors. This review summarizes knowledge of EPC and our current understanding of their function, together with what is known of the properties of genuine endothelial progenitor cells and how they will be used in the future to design more effective means of therapeutic angiogenesis.

Anti-beta2GPI-antibody-induced endothelial cell gene expression profiling reveals induction of novel pro-inflammatory genes potentially involved in primary antiphospholipid syndrome.

OBJECTIVE: To determine the effects of primary antiphospholipid syndrome (PAPS)-derived anti-beta(2)GPI antibodies on gene expression in human umbilical vein endothelial cells (HUVEC) by gene profiling using microarrays. METHODS: Anti-beta(2)GPI antibodies purified from sera of patients with PAPS or control IgG isolated from normal subjects were incubated with HUVEC for 4 h before isolation of RNA and processing for hybridisation to Affymetrix Human Genome U133A-2.0 arrays. Data were analysed using a combination of the MAS 5.0 (Affymetrix) and GeneSpring (Agilent) software programmes. For selected genes microarray data were confirmed by real-time PCR analysis or at the protein level by ELISA. RESULTS: A total of 101 genes were found to be upregulated and 14 genes were downregulated twofold or more in response to anti-beta(2)GPI antibodies. A number of novel genes not previously associated with APS were induced, including chemokines CCL20, CXCL3, CX3CL1, CXCL5, CXCL2 and CXCL1, the receptors Tenascin C, OLR1, IL-18 receptor 1, and growth factors CSF2, CSF3 IL-6, IL1beta and FGF18. The majority of downregulated genes were transcription factors/signalling molecules including ID2. Quantitative real-time RT-PCR analysis confirmed the microarray results for selected genes (CSF3, CX3CL1, FGF18, ID2, SOD2, Tenascin C). CONCLUSIONS: This study reveals a complex gene expression response in HUVEC to anti-beta(2)GPI antibodies with multiple chemokines, pro-inflammatory cytokines, pro-thrombotic and pro-adhesive genes regulated by these antibodies in vitro. Some of these newly identified anti-beta(2)GPI antibody-regulated genes could contribute to the vasculopathy associated with this disease.

Neutrophils in development of multiple organ failure in sepsis.

Multiple organ failure is a major threat to the survival of patients with sepsis and systemic inflammation. In the UK and in the USA, mortality rates are currently comparable with and projected to exceed those from myocardial infarction. The immune system combats microbial infections but, in severe sepsis, its untoward activity seems to contribute to organ dysfunction. In this Review we propose that an inappropriate activation and positioning of neutrophils within the microvasculature contributes to the pathological manifestations of multiple organ failure. We further suggest that targeting neutrophils and their interactions with blood vessel walls could be a worthwhile therapeutic strategy for sepsis.

Equilibrative nucleoside transporter 2 is expressed in human umbilical vein endothelium, but is not involved in the inhibition of adenosine transport induced by hyperglycaemia.

Human equilibrative, Na(+)-independent nucleoside transport is mediated by membrane proteins sensitive (system es, hENT1) or insensitive (system ei, hENT2) to nitrobenzylthioinosine (NBMPR). Gestational diabetes and elevated extracellular concentrations of D-glucose reduce adenosine transport in human umbilical vein endothelium (HUVEC). We studied hENT2 and hENT1 expression in HUVEC, and the effect of D-glucose on their activity and expression in HUVEC preincubated with 25 mM D-glucose (24 h). hENT2 and hENT1 mRNA were quantified by real-time reverse transcription polymerase chain reaction, and their proteins were detected by Western blotting. hENT2 and hENT1 proteins are co-expressed in HUVEC and are located at the plasma membrane, however, hENT2 was mainly cytoplasmatic and perinuclear in location. D-Glucose reduced hENT1 and hENT2 mRNA expression, but only hENT1 protein abundance at the plasma membrane. Adenosine transport was inhibited by D-glucose and NMBPR (1 microM) in intact cells and membrane vesicles. Hypoxanthine inhibited adenosine transport in the absence or in the presence of 1 microM NBMPR. D-Glucose reduced NBMPR maximal binding in intact cells, membrane vesicles, and plasma membrane fractions. In conclusion, the present study demonstrates that hENT2 and hENT1 are co-expressed in HUVEC, and even when adenosine transport is also mediated by hENT2, the hENT2-mediated transport activity is not involved in the d-glucose-induced down-regulation of total adenosine transport.

Functional relevance of antiemetic control. Experience using the FLIE questionnaire in a randomised study of the NK-1 antagonist aprepitant.

Little information exists on the functional impact of effective antiemetic protection. In the present study, the Functional Living Index-Emesis (FLIE), was used to assess patient-reported impact of chemotherapy-induced nausea and vomiting (CINV) after administration of a new NK-1 receptor antagonist (aprepitant). Cisplatin-treated patients in a double-blind randomised trial received either aprepitant+dexamethasone+ondansetron on day 1 and aprepitant+dexamethasone on days 2-5 or standard antiemetic therapy (dexamethasone and ondansetron on day 1 and dexamethasone on days 2-5). Emetic events, nausea ratings and rescue medications were recorded in a 5-day diary and the FLIE was completed on day 6. Compared with standard therapy, significantly more patients treated with the high dose aprepitant regimen achieved a Complete Response (71 vs 44%, P<0.001) and also reported no impact on daily life as indicated by the FLIE total score (84 vs 66%, P<0.01). Use of the FLIE demonstrated that improved control of emesis was highly effective in reducing the impact of CINV on patients' daily lives.

Assessing the impact of chemotherapy-induced nausea and vomiting on patients' daily lives: a modified version of the Functional Living Index-Emesis (FLIE) with 5-day recall.

BACKGROUND: The Functional Living Index-Emesis (FLIE), a patient-reported outcome measure, was originally developed to assess the impact of chemotherapy-induced nausea and vomiting (CINV) on patients' daily lives over the 3 days following chemotherapy. More recent studies of CINV include assessments covering the 5 days following chemotherapy in an effort to capture information during both the acute (within 24 h) and delayed (up to 5-7 days) phases of CINV. GOALS: To assess the measurement characteristics of a modified version of the FLIE with 5-day recall. Instrument reliability, validity, and missing data were assessed. PATIENTS AND METHODS: Data were collected from 183 patients receiving cisplatin >or=70 mg/m(2) as part of a phase IIb antiemetic trial of an NK-1 receptor antagonist (MK-0869). Patients recorded the number of vomiting episodes and nausea ratings in a 5-day daily diary. RESULTS: The 5-day FLIE had: (1) excellent internal consistency within FLIE Nausea and Vomiting domains (Cronbach's alpha 0.77-0.78), (2) acceptable construct validity shown by FLIE item-total correlations stronger within domains ( r=0.74-0.97) than across domains ( r=0.52-0.76), and (3) acceptable convergent validity as shown by moderate to strong correlations between FLIE domain scores and independent endpoints of emetic episodes, nausea ratings, and use of rescue medications. The extent of missing data was within acceptable limits with less than 2% of patients missing data. CONCLUSION: The 5-day FLIE had adequate measurement characteristics for studying the impact of CINV on patients' daily lives during the period covering both the acute and delayed phases.

Contemporary update of prostate cancer staging nomograms (Partin Tables) for the new millennium.

OBJECTIVES: We previously presented nomograms combining preoperative serum prostate-specific antigen (PSA), clinical (TNM) stage, and biopsy Gleason score to provide the likelihood of various final pathologic stages at radical retropubic prostatectomy. The data for the original nomograms were collected from men treated between 1982 and 1996. During the past 10 years, the stage at presentation has shifted, with more men presenting with Stage T1c, Gleason score 5 to 6, and serum PSA levels less than 10.0 ng/mL. In this work, we update the "Partin Tables" with a more contemporary cohort of men treated since 1994 and with revised PSA and Gleason categories. METHODS: Multinomial log-linear regression analysis was used to estimate the likelihood of organ-confined disease, extraprostatic extension, seminal vesicle or lymph nodal status from the preoperative PSA stratified as 0 to 2.5, 2.6 to 4.0, 4.1 to 6.0, 6.1 to 10.0, and greater than 10 ng/mL, clinical (AJCC-TNM, 1992) stage (T1c, T2a, T2b, or T2c), and biopsy Gleason score stratified as 2 to 4, 5 to 6, 3 + 4 = 7, 4 + 3 = 7, or 8 to 10 among 5079 men treated with prostatectomy (without neoadjuvant therapy) between 1994 and 2000 at Johns Hopkins Hospital. The average age was 58 years. RESULTS: In this cohort, more than 60% had T1c, more than 75% had Gleason score of 6, more than 70% had PSA greater than 2.5 and less than 10.0 ng/mL, and more than 60% had organ-confined disease. Nomograms of the robust estimated likelihoods and 95% confidence intervals were developed from 1000 bootstrap analyses. The probability of organ-confined disease improved across the groups, and further stratification of the Gleason score and PSA level allowed better differentiation of individual patients. CONCLUSIONS: These updated "Partin Tables" were generated to reflect the trends in presentation and pathologic stage for men newly diagnosed with clinically localized prostate cancer at our institution. Clinicians can use these nomograms to counsel individual patients and help them make important decisions regarding their disease.

Single ribosomal protein mutations in antibiotic-resistant bacteria analyzed by mass spectrometry.

Mutations in several ribosomal proteins are known to be related to antibiotic resistance. For several strains of Escherichia coli, the mutated protein is known but the amino acid actually altered has not been documented. Characterization of these determinants for antibiotic resistance in proteins will further the understanding of the precise mechanism of the antibiotic action as well as provide markers for resistance. Mass spectrometry can be used as a valuable tool to rapidly locate and characterize mutant proteins by using a small amount of material. We have used electrospray and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry to map out all 56 ribosomal proteins in E. coli based on intact molecular masses. We used this fingerprinting approach to locate variants of ribosomal proteins displaying a change in mass. In particular we have studied proteins responsible for streptomycin, erythromycin, and spectinomycin resistance in three strains of E. coli, and then we characterized each mutation responsible for resistance by analyzing tryptic peptides of these proteins by using MALDI-TOF and nanoelectrospray tandem mass spectrometry. The results provided markers for antibiotic resistance and demonstrated that mass spectrometry can be used to rapidly investigate changes in individual proteins from a complex with picomole amounts of protein.

A reference map of human lung MRC-5 fibroblast proteins using immobilized pH gradient-isoelectric focusing-based two-dimensional electrophoresis.

We report the first protein map of human adult lung MRC-5 fibroblasts using isoelectric focusing-immobilized pH gradient-based two-dimensional polyacrylamide gel electrophoresis. MRC-5 is an immortalised cell line used in a wide range of investigations. The two-dimensional gel pattern of proteins generated from any given cell system provides a fingerprint that is unique to those cells. Therefore, the establishment of a protein map for a particular cell system provides a useful reference tool as a "master map" for subsequent studies using those cells. In this map a total of 98 protein spots were identified by comparative searches of the nucleotide and protein database using peptide masses obtained by matrix-assisted laser desorption/ionization time of flight following trypsin digestion. To increase the utility of the reference map, cells were cultured in both Dulbecco's modified Eagle medium (DMEM), the standard medium, and Roswell Park Memorial Institute (RPMI)-1640. Two-dimensional gel protein patterns of MRC-5 cultures were shown to be largely unaffected by the use of RPMI compared to DMEM, respectively. In combination with the reference map, the standardised protocol described provides a tool for comparative studies involving MRC-5 cells in which nonspecific variation is minimized.

Agonist-specific cross talk between ERKs and p38(mapk) regulates PGI(2) synthesis in endothelium.

We have examined the mechanisms regulating prostacyclin (PGI(2)) synthesis after acute exposure of human umbilical vein endothelial cells (HUVEC) to interleukin-1 alpha (IL-1 alpha). IL-1 alpha evoked an early (30 min) release of PGI(2) and [(3)H]arachidonate that was blocked by the cytosolic phospholipase A(2)alpha (cPLA(2)alpha) inhibitor arachidonyl trifluoromethyl ketone. IL-1 alpha-mediated activation of extracellular signal-regulated kinase 1/2 (ERK1/2; p42/p44(mapk)) coincided temporally with phosphorylation of cPLA(2)alpha and with the onset of PGI(2) synthesis. The mitogen-activated protein kinase (MAPK) kinase (MEK) inhibitors, PD-98059 and U-0126, blocked IL-1 alpha-induced ERK activation and partially attenuated cPLA(2)alpha phosphorylation and PGI(2) release, suggesting that ERK-dependent and -independent pathways regulate cPLA(2)alpha phosphorylation. SB-203580 treatment enhanced IL-1 alpha-induced MEK, p42/44(mapk), and cPLA(2)alpha phosphorylation but reduced thrombin-stimulated MEK and p42/44(mapk) activation. IL-1 alpha, but not thrombin, activated Raf-1 as assessed by immune-complex kinase assay, as did SB-203580 alone. These results show that IL-1 alpha causes an acute upregulation of PGI(2) generation in HUVEC, establish a role for the MEK/ERK/cPLA(2)alpha pathway in this early release, and provide evidence for an agonist-specific cross talk between p38(mapk) and p42/44(mapk) that may reflect receptor-specific differences in the signaling elements proximal to MAPK activation.

Modulation of adenosine transport by insulin in human umbilical artery smooth muscle cells from normal or gestational diabetic pregnancies.

1. Adenosine transport was measured in human cultured umbilical artery smooth muscle cells, isolated from non-diabetic or gestational diabetic pregnancies, under basal conditions and after pretreatment in vitro with insulin. 2. Adenosine transport in non-diabetic smooth muscle cells was significantly increased by insulin (half-maximal stimulation at 0.33 +/- 0.02 nM, 8 h) and characterized by a higher maximal rate (V(max)) for nitrobenzylthioinosine (NBMPR)-sensitive (es) saturable nucleoside transport (17 +/- 5 vs. 52 +/- 12 pmol (microg protein)(-1) min(-1), control vs. insulin, respectively) and maximal binding sites (B(max)) for [(3)H]NBMPR (0.66 +/- 0.07 vs. 1.1 +/- 0.1 fmol (microg protein)(-1), control vs. insulin, respectively), with no significant changes in Michaelis-Menten (K(m)) and dissociation (K(d)) constants. 3. In contrast, in smooth muscle cells from diabetic pregnancies, where the values of V(max) for adenosine transport (59 +/- 4 pmol (microg protein)(-1) min(-1)) and B(max) for [(3)H]NBMPR binding (1.62 +/- 0.16 fmol (microg protein)(-1)) were significantly elevated by comparison with non-diabetic cells, insulin treatment (1 nM, 8 h) reduced the V(max) for adenosine transport and B(max) for [(3)H]NBMPR binding to levels detected in non-diabetic cells. 4. In non-diabetic cells, the stimulatory effect of insulin on adenosine transport was mimicked by dibutyryl cGMP (100 nM) and reduced by inhibitors of phosphatidylinositol 3-kinase (10 nM wortmannin), nitric oxide synthase (100 microM N (G)-nitro-L-arginine methyl ester, L-NAME) or protein synthesis (1 microM cycloheximide), whereas inhibition of adenylyl cyclase (100 microM SQ-22536) had no effect. 5. Wortmannin or SQ-22536, but not L-NAME or cycloheximide, attenuated the inhibitory action of insulin on the diabetes-induced stimulation of adenosine transport. 6. Protein levels of inducible NO synthase (iNOS) were similar in non-diabetic and diabetic cells, but were increased by insulin (1 nM, 8 h) only in non-diabetic smooth muscle cells. 7. Our results suggest that adenosine transport via the es nucleoside transporter is modulated differentially by insulin in either cell type. Insulin increased adenosine transport in non-diabetic cells via NO and cGMP, but inhibited the diabetes-elevated adenosine transport via activation of adenylyl cyclase, suggesting that the biological actions of adenosine may be altered under conditions of sustained hyperglycaemia in uncontrolled diabetes.

Cross-linking of brain endothelial intercellular adhesion molecule (ICAM)-1 induces association of ICAM-1 with detergent-insoluble cytoskeletal fraction.

Intercellular adhesion molecule (ICAM)-1 plays a vital role in the process of leukocyte transmigration through endothelial cell (EC) barriers and has been shown to mediate signal transduction events in ECs induced either by its cross-linking or by the binding of T lymphocytes. Immunoblotting of ICAM-1 of Triton X-100 detergent fractions demonstrated that the majority of ICAM-1 was contained within the detergent-soluble fraction (noncytoskeletal associated) under basal conditions. After cross-linking of endothelial ICAM-1 with monoclonal antibody or coculture with T lymphocytes, EC ICAM-1 was observed to partition with a Triton X-100-insoluble (cytoskeletal associated) fraction in a dose- and time-dependent manner. Redistribution of ICAM-1 was specific, inasmuch as no association with the Triton X-100-insoluble fraction was observed after cross-linking of vascular cell adhesion molecule-1, nor did cross-linking of ICAM-1 result in a redistribution of the platelet and EC adhesion molecule. ICAM-1 association with the endothelial cytoskeleton after cross-linking was unaffected after treatment of the cells with cytochalasin D, C3-transferase, removal of extracellular calcium ions, or chelation of intracellular calcium ions. These data show that ICAM-1 colocalizes with the endothelial cytoskeleton and associates with a detergent-insoluble fraction after cross-linking.

Fibroblast matrix gene expression and connective tissue remodeling: role of endothelin-1.

This study examines endothelin-induced modulation of extracellular matrix synthesis and remodeling by fibroblasts, and its potential role in the pathogenesis of systemic sclerosis (scleroderma). Endothelin-1 promoted fibroblast synthesis of collagen types I and III, but not fibronectin, by a mechanism dependent upon both ETA and ETB receptors. Conversely, endothelin-1 inhibited both protein expression of matrix metalloproteinase 1 and zymographic activity exclusively via ETA receptors. A dual regulatory role for endothelin-1 in transcriptional regulation was suggested by the ability of endothelin-1 to enhance steady-state levels of collagen mRNA and activate the proalpha2(I) collagen (Col1a2) promoter, but in contrast to reduce matrix metalloproteinase 1 transcript expression and suppress transcription of a human matrix metalloproteinase 1 promoter reporter construct in transient transfection assays. Although endothelin-1 significantly enhanced remodeling of three-dimensional collagen lattices populated by normal fibroblasts, this was not observed for lattices populated by systemic sclerosis fibroblasts. Promotion of matrix remodeling was dependent upon ETA receptor expression and was blocked by specific inhibitors of tyrosine kinases or protein kinase C. Reverse transcriptase polymerase chain reaction, S1 nuclease, and functional cell surface binding studies showed that normal and systemic sclerosis fibroblasts express both ETA and ETB receptors (predominantly ETA), but that ETA receptor mRNA levels and ETA binding sites on fibroblasts cultured from systemic sclerosis skin biopsies are reduced by almost 50%. Endothelin-1 is thus able to induce a fibrogenic phenotype in normal fibroblasts that is similar to that of lesional systemic sclerosis fibroblasts. Moreover, reduced responsiveness to exogenous endothelin-1 in systemic sclerosis suggests that downstream pathways may have already been activated in vivo. These data further implicate dysregulated endothelin-receptor pathways in fibroblasts in the pathogenesis of connective tissue fibrosis.

Vasoactive mediator release by fetal endothelial cells in intrauterine growth restriction and preeclampsia.

OBJECTIVE: Preeclampsia and fetal growth restriction are associated with poor placental perfusion, which may be accompanied by a compensatory release of vasoactive substances in the fetoplacental circuit. This study examines the effects of preeclampsia and fetal growth restriction on nitric oxide and prostacyclin signaling pathways in fetal endothelial cells. STUDY DESIGN: Human umbilical vein endothelial cells from 30 control pregnancies, 18 pregnancies with preeclampsia, and 9 pregnancies with intrauterine growth restriction were cultured. Intracellular cyclic guanosine monophosphate accumulation and 6-keto-prostaglandin F1alpha production were determined. RESULTS: Intracellular accumulation of cyclic guanosine monophosphate was significantly higher in the preeclampsia group and lower in the growth restriction group than in the control group (9.8, 1.8, and 3.9 pmol/microg protein for 5 minutes, respectively), whereas 6-keto-prostaglandin F1alpha production was not significantly different in the 3 groups. CONCLUSION: The data suggest that the fetoplacental vascular response to preeclampsia is to increase production of cyclic guanosine monophosphate, perhaps to maintain vessel dilatation and maximum flow through placental villi. In fetal growth restriction the umbilical vein endothelial cells do not or cannot respond to chronic hypoxia by increasing cyclic guanosine monophosphate, which may lead to fetoplacental vasoconstriction.

Impaired response to interferon-gamma in activated macrophages due to tyrosine nitration of STAT1 by endogenous nitric oxide.

1. Inducible NO synthase (iNOS) expression and activity were measured in the mouse macrophage cell line J774 after exposure to bacterial lipopolysaccharide (LPS) with or without interferon-gamma (IFN-gamma). 2. Inhibition of NOS activity by concomitant N(G)-monomethyl-L-arginine (L-NMMA) treatment further increased iNOS protein levels, with a substantial increase in iNOS half-life. 3. Western blotting and ELISA demonstrated that several cell proteins were tyrosine-nitrated when iNOS activity was high. 4. Rapid IFN-gamma-induced phosphorylation of STAT1 was reduced by about 40% when cells were pretreated to induce iNOS, unless L-NMMA was present during the pretreatment period. 2D gel electrophoresis demonstrated the presence of nitrotyrosine in STAT1 after iNOS induction, and confirmed the reduction in phospho-STAT1 on subsequent stimulation with IFN-gamma for 15 min and its partial restoration when L-NMMA was present during the pretreatment period. 5. We did not detect tyrosine nitration of the upstream kinase JAK2 in LPS+IFN-gamma pretreated cells, but JAK2 activity was also impaired, and was partially restored by concomitant L-NMMA pretreatment. 6. We conclude that endogenous production of NO induces feedback inhibition of signalling pathways activated by IFN-gamma, at least in part by nitrating tyrosine residues in STAT1 which prevents phosphorylation.

Vascular smooth muscle cells : isolation, culture, and characterization.

In blood vessel development (vasculogenesis) smooth muscle cells (SMCs) are derived by differentiation of mesenchymal cells under the influence of mediators secreted by the endothelial cells (ECs) composing newly formed vessels. In angiogenesis, SMCs can be formed in the same way or by proliferation of existing SMCs (1). Key events in the development of atherosclerotic lesions and restenosis of arteries are now recognized to include vascular SMC migration, hyperplasia, and hypertrophy (2). This has led to an increase in studies of SMC function in response to growth factors, extracellular matrix, and lipoproteins, under controlled in vitro conditions, to address the cellular mechanisms in atherogenesis. Most of the methodology used for vascular smooth muscle culture has been developed for such studies (3).

Regulation of adenosine transport by D-glucose in human fetal endothelial cells: involvement of nitric oxide, protein kinase C and mitogen-activated protein kinase.

The effects of elevated D-glucose on adenosine transport were investigated in human cultured umbilical vein endothelial cells isolated from normal pregnancies. Elevated D-glucose resulted in a time- (8-12 h) and concentration-dependent (half-maximal at 10+/-2 mM) inhibition of adenosine transport, which was associated with a reduction in the Vmax for nitrobenzylthioinosine (NBMPR)-sensitive (es) saturable nucleoside with no significant change in Km. d-Fructose (25 mM), 2-deoxy-D-glucose (25 mM) or D-mannitol (20 mM) had no effect on adenosine transport. Adenosine transport was inhibited following incubation of cells with the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA; 100 nM, 30 min to 24 h). D-Glucose-induced inhibition of transport was abolished by calphostin C (100 nM, an inhibitor of PKC), and was not further reduced by PMA. Increased PKC activity in the membrane (particulate) fraction of endothelial cells exposed to D-glucose or PMA was blocked by calphostin C but was unaffected by NG-nitro-L-arginine methyl ester (L-NAME; 100 microM, an inhibitor of nitric oxide synthase (NOS)) or PD-98059 (10 microM, an inhibitor of mitogen-activated protein kinase kinase 1). D-Glucose and PMA increased endothelial NOS (eNOS) activity, which was prevented by calphostin C or omission of extracellular Ca2+ and unaffected by PD-98059. Adenosine transport was inhibited by S-nitroso-N-acetyl-l, d-penicillamine (SNAP; 100 microM, an NO donor) but was increased in cells incubated with L-NAME. The effect of SNAP on adenosine transport was abolished by PD-98059. Phosphorylation of mitogen-activated protein kinases p44mapk (ERK1) and p42mapk (ERK2) was increased in endothelial cells exposed to elevated D-glucose (25 mM for 30 min to 24 h) and the NO donor SNAP (100 microM, 30 min). The effect of D-glucose was blocked by PD-98059 or L-NAME, which also prevented the inhibition of adenosine transport mediated by elevated D-glucose. Our findings provide evidence that D-glucose inhibits adenosine transport in human fetal endothelial cells by a mechanism that involves activation of PKC, leading to increased NO levels and p42-p44mapk phosphorylation. Thus, the biological actions of adenosine appear to be altered under conditions of sustained hyperglycaemia.

Validation of Partin tables for predicting pathological stage of clinically localized prostate cancer.

PURPOSE: The accurate prediction of pathological stage of prostate cancer using preoperative factors is a critical aspect of treatment. In 1997 Partin et al published tables predicting pathological stage using clinical stage, Gleason score and prostate specific antigen (PSA). We tested the validity of the Partin tables. MATERIALS AND METHODS: From 1990 to 1996 inclusively 5,780 patients underwent bilateral pelvic lymphadenectomy and radical prostatectomy for prostate cancer at the Mayo Clinic. However, only 2,475 of these patients met all inclusion criteria of no preoperative treatment, known biopsy Gleason score, available preoperative PSA done either before biopsy or more than 28 days after biopsy and clinical stage T1, T2 or T3a. Among the 2,475 patients 15 had positive lymph nodes and planned prostatectomy was abandoned. The receiver operating characteristics (ROC) curve area, observed and predicted Partin rates of each pathological stage, and positive and negative predictive values were used to compare the Mayo study to the Partin tables. RESULTS: The distribution of pathological stage was organ confined in 67% of Mayo cases versus 48% in the Partin study, extracapsular without seminal vesicle or node involvement in 18% versus 40%, seminal vesicle involvement without nodes in 9% versus 7% and were positive nodes in 6% versus 5%. Using the predicted probabilities of Partin et al the ROC curve area for predicted node positive disease was 0.84 for Mayo cases compared to an estimated 0. 82 in the Partin series. The ROC curve area for predicting organ confined cancer was 0.76 for the Mayo Clinic compared to an estimated 0.73 for the Partin series. The observed rates of node positive disease were similar to those predicted (Partin) based on clinical stage, PSA and Gleason score. For organ confined disease Mayo rates were consistently higher than those predicted from the Partin series using a cut point of 0.50 or greater. Positive and negative predictive values were 0.83 and 0.49 versus 0.63 and 0.70 for the Mayo Clinic and Partin series. CONCLUSIONS: Our study provides strong evidence that sensitivity and specificity of the Partin tables for external clinical sites are similar to what was reported.