The relation between endothelial dependent flow mediated dilation of the brachial artery and coronary collateral development – a cross sectional study

<p>Abstract</p> <p>Background</p> <p>Endothelial dysfunction is thought to be a potential mechanism for the decreased presence of coronary collaterals. The aim of the study was to investigate the association between systemic endothelial function and the extent of coronary collaterals.</p> <p>Methods</p> <p>We investigated the association between endothelial function assessed via flow mediated dilation (FMD) of the brachial artery following reactive hyperemia and the extent of coronary collaterals graded from 0 to 3 according to Rentrop classification in a cohort of 171 consecutive patients who had high grade coronary stenosis or occlusion on their angiograms.</p> <p>Results</p> <p>Mean age was 61 years and 75% were males. Of the 171 patients 88 (51%) had well developed collaterals (grades of 2 or 3) whereas 83 (49%) had impaired collateral development (grades of 0 or 1). Patients with poor collaterals were significantly more likely to have diabetes (<it>p </it>= 0.001), but less likely to have used statins (<it>p </it>= 0.083). FMD measurements were not significantly different among good and poor collateral groups (11.5 ± 5.6 vs. 10.4 ± 6.2% respectively, <it>p </it>= 0.214). Nitroglycerin mediated dilation was also similar (13.4 ± 5.9 vs. 12.8 ± 6.5%, <it>p </it>= 0.521).</p> <p>Conclusion</p> <p>No significant association was found between the extent of angiographically visible coronary collaterals and systemic endothelial function assessed by FMD of the brachial artery.</p

Non-invasive diagnostic tests for Helicobacter pylori infection

BACKGROUND: Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori. OBJECTIVES: To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started. SEARCH METHODS: We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively. SELECTION CRITERIA: We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as13C or14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities. MAIN RESULTS: We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons. AUTHORS' CONCLUSIONS: In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions

1,3-Propanediol production potential of Clostridium saccharobutylicum NRRL B-643

WOS: 000285896200010PubMed ID: 20647065Owing to the significant interest in biofuel production in the form of biodiesel, vast amount of glycerol as a waste product is produced all over the world Among the economically viable and ecologically acceptable solutions for the safe disposal of this waste, biotechnological conversion of glycerol into a valuable bioplastic raw material, namely 1,3-propanediol (1,3-PDO) seems to be very promising In this study, 1,3-PDO production potential of Clostridium saccharobutylicum NRRL B-643 was studied and the results were compared with other types of anaerobic microorganisms (Clostridium spp, Pantoea agglomerans, Ochrobactrum anthropi, Chyreseomonas luteola, and Klebsiella pneumoniae) and aerobic microorganisms (Lactobacillus spp) The results were important for understanding the significance of C saccharobutylicum NRRL B-643 among other well-known 1,3-PDO producer species According to the screening results only C saccharobutylicum (B-643) was able to consume feed glycerol almost entirely However, 1,3-PDO production yield was found to be 0 36 mol/mol which is lower than that of Clostiridium beijerinckii (B-593) B-593 showed the highest value of production yields with 0 54 mol/mol This microorganism is seen as a promising type for further 1,3-PDO studies, because it has the highest substrate utilization percentage among others In this regard, this microorganism may have an important role in tolerating and converting glycerol during fermentation into 1,3-PD

A distributed behavioral model for landmine detection robots

This paper presents a distributed navigation, detection and swarming model for a group of minimalist identical robotic agents. Decision making process of agents is weight based in contrast to widely used precedence based rules. The group is indirectly controlled by an alpha agent that has more sophisticated systems. Computer simulations of the proposed behavioral model generated promising results

A Case of Placenta Increta Mimicking Submucous Leiomyoma

In recent years with the increase in cesarean section rates, the frequency of placenta accreta cases rises. It causes 33–50% of all emergency peripartum hysterectomies. We present a 42-year-old case who was caught with early postpartum hemorrhage due to retained placental products. The ultrasonography showed a 65 × 84 mm mass in the uterine cavity after the delivery. Due to presence of early postpartum hemorrhage which needs transfusion, an intervention decision was made. The patient underwent curettage but the mass could not be removed so that placental retention was ruled out. Submucous leiomyoma was made as first-prediagnosis. Hysterectomy operation was performed as a curative treatment. Placenta increta diagnosis was made as a final diagnosis with pathological examination. As a result, placental attachment disorders may be overlooked if it is not a placenta previa case

The relationship between coronary collateral artery development and inflammatory markers

Objective: This study aims to show the effect of myeloperoxidase (MPO), hsCRP, TNF-alpha values and leukocyte count on the development of coronary collateral arteries in patients with severely diseased coronary arteries. Methods: Current study is an observational cross-sectional study. In the study, 295 patients who had functional obstruction or total coronary occlusion at least 1 month on their angiograms were included. We divided the study population into two groups according to their collateral grade as good collateral (Group 1) (169 patients) and poor collateral (Group 2) (126 patients). Multiple logistic regression analysis was used for independent variables associated with the coronary collateral grade. Results: History of stable angina pectoris was statistically more prevalent in good collateral group (61.5% and 48.4%, p=0.025). Furthermore, MPO activation was higher in good collateral group and the difference was statistically significant (3.7 U/mL and 3.0 U/mL p=0.001). In multiple logistic regression analysis, stable angina pectoris [OR 1.7, 95% CI (1.05-2.8), p=0.03] and high MPO levels [OR 2.7, 95% CI (1.7-4.3), p<0.001] were found to be independent predictors of good collateral development. Conclusion: We think that proinflammatory enzymes and cytokines released from these cells rather than inflammatory cells themselves may play an important role on the collateral development

Urinary neutrophil gelatinase-associated lipocalin is associated with preeclampsia in a cohort of Turkish women

Purpose: We investigated the optimal cut-off level for urinary neutrophil gelatinase-associated lipocalin (NGAL) in preeclamptic patients to confirm the diagnosis. Methods: Urinary NGAL concentrations were measured by specific enzyme-linked immunosorbent assay (ELISA). Results: Patients with preeclampsia had significantly higher urinary NGAL concentrations than controls (mean: 387 ng/ml vs. 188 ng/ml, respectively; P< 0.001). Using a cutoff value 252 ng/ml for urinary NGAL to confirm diagnosis of preeclampsia, sensitivity, and specificity were 92% and 91%, respectively. Conclusion: Urinary NGAL concentrations were significantly elevated in women with preeclampsia versus normotensive controls