Classification and regression tree analysis of acute-on-chronic hepatitis B liver failure: Seeing the forest for the trees.

At present, there is no ideal model for predicting the short-term outcome of patients with acute-on-chronic hepatitis B liver failure (ACHBLF). This study aimed to establish and validate a prognostic model by using the classification and regression tree (CART) analysis. A total of 1047 patients from two separate medical centres with suspected ACHBLF were screened in the study, which were recognized as derivation cohort and validation cohort, respectively. CART analysis was applied to predict the 3-month mortality of patients with ACHBLF. The accuracy of the CART model was tested using the area under the receiver operating characteristic curve, which was compared with the model for end-stage liver disease (MELD) score and a new logistic regression model. CART analysis identified four variables as prognostic factors of ACHBLF: total bilirubin, age, serum sodium and INR, and three distinct risk groups: low risk (4.2%), intermediate risk (30.2%-53.2%) and high risk (81.4%-96.9%). The new logistic regression model was constructed with four independent factors, including age, total bilirubin, serum sodium and prothrombin activity by multivariate logistic regression analysis. The performances of the CART model (0.896), similar to the logistic regression model (0.914, P=.382), exceeded that of MELD score (0.667, P<.001). The results were confirmed in the validation cohort. We have developed and validated a novel CART model superior to MELD for predicting three-month mortality of patients with ACHBLF. Thus, the CART model could facilitate medical decision-making and provide clinicians with a validated practical bedside tool for ACHBLF risk stratification.

Fluid shear stress activation of egr-1 transcription in cultured human endothelial and epithelial cells is mediated via the extracellular signal-related kinase 1/2 mitogen-activated protein kinase pathway.

The primary response transcription factor, early growth response-1 (Egr-1), is rapidly activated by a variety of extracellular stimuli. Egr-1 binds to a sequence found in the promoters of genes involved in vascular injury, such as PDGF-A and tissue factor, and trans-activates their expression in endothelial cells in response to fluid shear stress. Here we show that egr-1 mRNA is increased after 30 min of flow in human aortic endothelial cell and HeLa cell cultures. Transient transfection of HeLa cells with reporter gene constructs driven by the murine or human egr-1 5' flanking sequence revealed a five- and ninefold induction, respectively, in transcriptional activity after exposure to a shear stress of 5 dynes/cm2 for 3 h. Deletion of sequences in the murine promoter containing two AP1 sites and an inhibitory Egr-1 binding sequence, did not reduce shear stress inducibility. However, progressive deletion of five serum response elements, reduced both the basal promoter activity and its capacity to be activated by shear stress. Further examination indicated that the three upstream serum response elements are predominantly responsible for shear stress activation of the egr-1 promoter. Treatment of cells with PD98059, a specific inhibitor of mitogen-activated protein kinase-1 inhibited shear stress activation of egr-1. We suggest that egr-1 activation by shear stress involves activation of Elk-1 but not c-jun activity. These data, which are consistent with previous findings for shear mediated signaling via the mitogen-activated protein kinase cascade, now implicate shear modulation of the Egr-1 transcription factor in this pathway.

Characterization of a selective and potent antagonist of human P2X(7) receptors, AZ11645373.

BACKGROUND AND PURPOSE: The ATP-gated P2X(7) receptor has been shown to play a role in several inflammatory processes, making it an attractive target for anti-inflammatory drug discovery. We have recently identified a novel set of cyclic imide compounds that inhibited P2X(7) receptor-mediated dye uptake in human macrophage THP-1 cells. In this study the actions and selectivity of one of these compounds, AZ11645373, were characterized. EXPERIMENTAL APPROACH: We measured membrane currents, calcium influx, and YOPRO-1 uptake from HEK cells expressing individual P2X receptors, and YOPRO1 uptake and interleukin-1beta release from THP-1 cells in response to ATP and the ATP analogue benzoylbenzoyl ATP (BzATP). KEY RESULTS: AZ11645373 up to 10 microM, had no agonist or antagonist actions on membrane currents due to P2X receptor activation at human P2X(1), rat P2X(2), human P2X(3), rat P2X(2/3), human P2X(4), or human P2X(5) receptors expressed in HEK cells. AZ11645373 inhibited human P2X(7) receptor responses in HEK cells in a non-surmountable manner with K (B) values ranging from 5 - 20 nM, with mean values not significantly different between assays. K (B) values were not altered by removing extracellular calcium and magnesium. ATP-evoked IL-1beta release from lipopolysaccharide-activated THP-1 cells was inhibited by AZ11645373, IC(50) = 90 nM. AZ11645373 was > 500-fold less effective at inhibiting rat P2X(7) receptor-mediated currents with less than 50% inhibition occurring at 10 microM. CONCLUSIONS AND IMPLICATIONS: AZ11645373 is a highly selective and potent antagonist at human but not rat P2X(7) receptors and will have much practical value in studies of human cells.

Systematic review with network meta-analysis: the comparative effectiveness and safety of interventions in patients with overt hepatic encephalopathy.

BACKGROUND: Interventional treatment for overt hepatic encephalopathy (OHE), includes non-absorbable disaccharides, neomycin, rifaximin, L-ornithine-L-aspartate and branched chain amino acids (BCAA). However, the optimum regimen remains inconclusive. AIM: To compare interventions in terms of patients' adverse events and major clinical outcomes. METHODS: Literature search of PubMed, Embase, Scopus, and Cochrane Library studies published up to July 31 2014. RCTs of above interventions in OHE patients were included. Network meta-analysis combined direct and indirect evidence to estimate odds ratios (ORs) and mean difference (MD) between treatments and the probabilities of ranking for treatment based on clinical outcomes. RESULTS: Twenty eligible RCTs were included. When compared with observation, only L-ornithine-L-aspartate (OR 3.71, P < 0.001) and BCAA (OR 3.37, P < 0.001) improved clinical efficacy significantly. However, when L-ornithine-L-aspartate was compared with BCAA, non-absorbable disaccharides and neomycin, there was a trend suggesting that L-ornithine-L-aspartate may be the most effective intervention with respect to clinical improvement (OR 1.10), rifaximin (OR 1.31), non-absorbable disaccharides (OR 2.75), neomycin (OR 2.22). In addition, L-ornithine-L-aspartate (MD -20.18, 95% CI -40.12 to -0.27) provided a significant reduction in blood ammonia concentration compared with observation. Neomycin appeared to be associated with more adverse events in comparison with non-absorbable disaccharides (OR 10.15), rifaximin (OR 17.31), L-ornithine-L-aspartate (OR 3.16) or BCAA (OR 7.69). CONCLUSIONS: L-ornithine-L-aspartate treatment may show a trend in superiority for clinical efficacy among standard interventions for OHE. Rifaximin shows the greatest reduction in blood ammonia concentration, and treatment with neomycin demonstrates a higher probability in causing adverse effects among the five compared interventions.

Delivery and expression of fluid shear stress-inducible promoters to the vessel wall: applications for cardiovascular gene therapy.

In atherosclerosis, endothelial cells at sites of stenosis experience elevated levels of shear stress. We have constructed a series of shear stress-inducible transcription units (SITUs) expressing the luciferase reporter gene and determined their activation by fluid shear stress in transfected endothelial cells. Chimeric promoters were constructed that comprised basal transcription factor-binding sites coupled to a shear stress response element (SSRE). We have used consensus binding sites for transcription factors NF-kappaB, Ap1, Sp1, Oct1, and Egr-1/Sp1 in either the presence or absence of the previously defined "GAGACC" SSRE. The response of the promoters to shear stress was determined after transfection into human umbilical vein endothelial cells (HUVECs). After transient transfection into HUVECs, fluid shear stress activated the promoters by between two- and eightfold. The most responsive SITUs comprised an overlapping Sp1/Egr-1-binding site linked to a TATA box with (SP5) or without (SP7) the GAGACC SSRE. Instillation of SP5 DNA in vivo into the left carotid artery of rabbit and subsequent generation of a stenosis using a mechanical wire occluder caused a 10-fold upregulation of luciferase reporter gene expression at the site of vessel occlusion. These vectors show promise for therapeutic gene expression at sites of occlusive vascular disease.

Tissue repair with a therapeutic transcription factor.

The healing of tissue involves a wide range of molecular, cellular, and physiological events that are coordinated in a temporally specific manner. The cellular transcription factor early growth response factor 1 (Egr-1) is expressed minutes after acute injury and serves to stimulate the production of a class of growth factors whose role is to promote tissue repair. We have studied the effects of Egr-1 expression at the site of dermal wounding in rodents. We find that Egr-1 promotes angiogenesis in vitro and in vivo, increases collagen production, and accelerates wound closure. These results show that Egr-1 gene therapy accelerates the normal healing process and raises the potential use of this therapeutic transcription factor for any aspect of tissue repair.

Homing markers for atherosclerosis: applications for drug delivery, gene delivery and vascular imaging.

Endothelial dysfunction plays a major role in the pathogenesis of atherosclerosis. Pro-inflammatory cytokines such as interleukin-1 beta and tumour necrosis factor alpha activate endothelial cells changing their resting phenotype to become pro-adhesive, pro-thrombotic and pro-atherogenic. Phage display in vivo biopanning has been used to identify peptide sequences that home to diseased regions of the vessel wall in low density lipoprotein receptor (LDLr) knockout mice. In LDLr knockout mice, peptide sequence determinants exhibiting organ specificity have been isolated. These sequences have applications for gene delivery, drug delivery and for improving contrast agents for vascular imaging.

Work-related injury among Connecticut minors.

Work-related injuries have recently been shown to be a significant cause of morbidity among adolescents. This study represents a population-based work-related injury profile for Connecticut minors. Review of 796 worker compensation reports for adolescents from 14 through 17 years of age submitted over 12 months revealed an overall age-specific injury rate of 15 per 1000 employed 16- and 17-year-olds; frequency of injury increased with age. Social and recreational workers had an injury rate of more than 20%, predominantly sprains and contusions. Among all other occupations and industries, cuts were the major type of injury (34%); more than one third of cutting injuries were associated with use of case cutters, another third with knives. There were no work-related deaths among minors in this study. Minors in the workplace are at high risk of injury compared with adults. This study suggests that identification of specific patterns of work-related injury could lead to targeted intervention strategies.

Population, income, and ecological correlates of child pedestrian injury.

Pedestrian injury is a significant health problem among urban children. This study is an analysis of the role of population, income, and ecological factors in the occurrence of child pedestrian collisions. One hundred and ninety-eight motor vehicle collisions occurring in Hartford, Connecticut involving pedestrians younger than 15 years old were reported to police during 1986 through 1987. Collision locations were abstracted from police reports and assigned a census tract. Census tracts were classified as "high frequency" (8+ collisions), "moderate frequency" (3 to 7 collisions), or "low frequency" (0 to 2 collisions). High-frequency census tracts had greater proportions of children and of nonwhite residents than moderate- or low-frequency tracts. They also were characterized by high proportions of households headed by females living below the poverty line. High-frequency tracts had a greater number of children per acre than moderate or low tracts. Children per acre had the strongest association with collision frequency (R = .72) and remained the most consistent when other variables were controlled. The number of children per acre is a potentially useful predictor of census tracts at risk for child pedestrian collisions. This may be useful in developing focused prevention strategies within an urban environment.

Variations in pregnancy outcomes by race among 10-14-year-old mothers in the United States.

This study used the 1983-86 U.S. Linked Live Birth-Infant Death Files to examine variations in pregnancy outcomes among 38,551 U.S. resident black and white adolescents ages 10 through 14. The birth rate was 4.29 per 1,000 for blacks, more than 7 times the rate for whites (.59 per 1,000). Black mothers had higher proportions of very low and low birth weight infants than did whites (very low birth weight: 3.7 versus 2.6; low birth weight: 15.0 versus 10.5). Neonatal and infant mortality rates were higher among very low birth weight and low birth weight white infants. Neonatal and infant mortality rates were similar for normal birth weight infants of both races, but were 3.7 to 7.4 times higher among black infants with birth weights more than 4,250 grams. Logistic regression indicated that black mothers were at higher risk for having infants who were low birth weight, very low birth weight, small for gestational age, preterm, and very preterm. There were no differences by race for neonatal, postneonatal, and infant mortality. While the risk for poor pregnancy outcomes is great among young adolescents, young black adolescents appear to be particularly vulnerable. Attempts to reduce unintended pregnancies in this group should receive highest priority.

Accuracy of fatal motorcycle-injury reporting on death certificates.

This study identifies differences in motorcycle injury fatality statistics gathered from different sources. Police Accidents Reports (PARs), identifying fatal motorcycle injuries occurring in Connecticut during 1987 were matched with state death certificates. Matched death certificates were analyzed in three major areas: content, coding, and motorcycle fatality reporting. Death certificates underreported motorcycle fatalities by 38% compared to PARs. Forty percent of death certificates were missing some or all of the required information: 7 did not include the word motorcycle, 18 did not contain acceptable ICD-9 terminology for a motorcyclist, and 17 did not describe how the injury occurred. Forty-one percent of death certificates contained external cause of injury code (E-code) errors. Incomplete information on death certificates was responsible for 52% of inaccurate reporting and E-code errors for 48%. The accuracy of fatal motorcycle injury cause of death reporting on death certificates could be improved by better physician training and rapid implementation of both the computerized death certificate coding systems and upcoming ICD-10 classification system.

Full promoter sequence of human early growth response factor-1 (Egr-1): demonstration of a fifth functional serum response element.

The early growth response factor-1 (Egr-1) gene encodes a zinc finger transcription factor which is critical for cell proliferation and differentiation. The human Egr-1 promoter comprises regulatory elements including two Sp1 sites, an AP1 site, two cAMP response elements and an Egr-1 binding site. In addition to these transcription factor binding sites, the promoter harbours five serum response elements (SREs) and associated binding sites for the Ets transcription factor family, previously identified from partial sequence data (Sakamoto et al, Oncogene 6; 867-871, 1991). We now report the full sequence of the human Egr-1 promoter and confirm the presence of a fifth serum response element. This element is functionally active in a minimal promoter vector in response to the MAP kinase kinase MEK1.

Medical assessment of children going into emergency out-of-home placement.

Approximately 500,000 children and infants go into out-of-home placement in the United States each year. Increased attention is being given to the health care of children as they enter and remain in placement. This article describes a model, which has been in operation for 5 years, that provides medical assessments of children as they enter emergency out-of-home placement. The model is a community partnership with the county social service department, the police department, and the hospital. A computerized database that contains records for each child, including medical findings, has been helpful in developing a profile of the children served and contributes to continuity of care.

Calculating the costs of gun injuries. A new methodology.

A new method for assessing the costs of gun injuries to a health system examines data on paid amounts, comprehensive medical expenses, and expenses over time. The authors extracted claims using injury diagnosis codes from billing forms and medical charts. The study demonstrates that a claims database can be used to accurately measure health care costs associated with gun injuries. The study is the first to include gun-related injuries treated in ambulatory care settings and to track actual payments over time.

Barriers to screening and counseling pregnant women for alcohol use.

The consequences of fetal alcohol exposure are far-reaching and preventable. Health care providers are uniquely positioned to promote alcohol-free pregnancy, yet an array of factors inhibit routine screening, counseling, and referral. This descriptive, qualitative study explored experiences and perceived barriers related to prenatal screening for alcohol use. The study included eight focus groups (71 participants) and 41 key informant interviews with health care professionals representing a mix of disciplines. Nearly 40% of the providers were physicians who regularly encounter women in their practices. While most providers ask about alcohol use, few probe in depth or follow up. The findings should alert program planners and medical educators to strengthen their preventive medical and public health practices.

Nifedipine-induced gingival hyperplasia.

Gingial hyperplasia is a complication which may be seen in a significant number of patients taking nifedipine (Procardia, Pfizer) a commonly used medication for cardiac vessel dilitation. This is a report of gingival changes in a 43-year-old hypertensive male who began using the calcium channel blocking agent during his active dental treatment. Gingival hyperplasia developed which was severe enough to alter the course of his dental treatment and prompt his changing to other medications to control his blood pressure. The recognition that the drug was responsible for the hyperplasia led to prompt and effective methods to resolve this problem.

Systematic review with network meta-analysis: adjuvant therapy for resected biliary tract cancer.

BACKGROUND: Major adjuvant therapies for biliary tract cancer (BTC) include fluorouracil, gemcitabine and chemoradiation (CRT), but the optimum regimen remains inconclusive. AIM: To compare these therapies in terms of patient survival rates after resection and toxic effects. METHODS: We searched PubMed for controlled trials comparing the above three therapies with each other or observation alone until 31 January 2014. We estimated the hazard ratios (HRs) for death and odds ratios (ORs) for toxic effects among different therapies. Subgroup analyses based on positive lymph node or resection margin were also performed. RESULTS: Twelve eligible articles were included. Gemcitabine improved 5-year survival (HR 2.12, 95% CI, confidence interval 1.23-4.02, P = 0.01), whereas fluorouracil (HR 1.61, 95% CI 0.74-3.67) and CRT (HR 1.55, 95% CI 0.82-3.32) provided a poorer survival outcome compared with gemcitabine after 1 year. Similarly, for 5-year survival rates, although differing, CRT did not provide a significant improvement in survival (HR 0.46, 95% CI 0.20-0.97) compared with gemcitabine. Fluorouracil did not appear to provide benefit over gemcitabine (HR 1.56, 95% CI 0.77-3.35). CRT was ranked highest for toxic effects including haematological (OR 5.45, 95% CI 0.01-483.85) and nonhaematological (OR 5.77, 95% CI 0.01-3807.40). CONCLUSIONS: Chemotherapy with gemcitabine is the optimum adjuvant treatment with a balanced benefit-toxicity ratio for resected biliary tract cancer. Chemoradiation was more likely to cause toxic effects.

The contribution of VEGF signalling to fostamatinib-induced blood pressure elevation.

BACKGROUND AND PURPOSE: Fostamatinib is an inhibitor of spleen tyrosine kinase (TK). In patients, fostamatinib treatment was associated with increased BP. Some TK inhibitors cause BP elevation, by inhibiting the VEGF receptor 2 (VEGFR2). Here, we have assessed the mechanistic link between fostamatinib-induced BP elevation and inhibition of VEGF signalling. EXPERIMENTAL APPROACH: We used conscious rats with automated blood sampling and radio telemetry and anaesthetized rats to measure cardiovascular changes. Rat isolated aorta and isolated hearts, and human resistance vessels in vitro were also used. NO production by human microvascular endothelial cells was measured with the NO-dependent probe, DAF-FM and VEGFR2 phosphorylation was determined in mouse lung, ex vivo. KEY RESULTS: In conscious rats, fostamatinib dose-dependently increased BP. The time course of the BP effect correlated closely with the plasma concentrations of R406 (the active metabolite of fostamatinib). In anaesthetized rats, infusion of R406 increased BP and decreased femoral arterial conductance. Endothelial function was unaffected, as infusion of R406 did not inhibit hyperaemia- or ACh-induced vasodilatation in rats. R406 did not affect contraction of isolated blood vessels. R406 inhibited VEGF-stimulated NO production from human endothelial cells in vitro, and treatment with R406 inhibited VEGFR2 phosphorylation in vivo. R406 inhibited VEGF-induced hypotension in anaesthetized rats. CONCLUSIONS AND IMPLICATIONS: Increased vascular resistance, secondary to reduced VEGF-induced NO release from endothelium, may contribute to BP increases observed with fostamatanib. This is consistent with the elevated BP induced by other drugs inhibiting VEGF signalling, although the contribution of other mechanisms cannot be excluded.