Autotrophy as a predominant mode of carbon fixation in anaerobic methane-oxidizing microbial communities

The methane-rich, hydrothermally heated sediments of the Guaymas Basin are inhabited by thermophilic microorganisms, including anaerobic methane-oxidizing archaea (mainly ANME-1) and sulfate-reducing bacteria (e.g., HotSeep-1 cluster). We studied the microbial carbon flow in ANME-1/ HotSeep-1 enrichments in stable-isotope–probing experiments with and without methane. The relative incorporation of ¹³C from either dissolved inorganic carbon or methane into lipids revealed that methane-oxidizing archaea assimilated primarily inorganic carbon. This assimilation is strongly accelerated in the presence of methane. Experiments with simultaneous amendments of both ¹³C-labeled dissolved inorganic carbon and deuterated water provided further insights into production rates of individual lipids derived from members of the methane-oxidizing community as well as their carbon sources used for lipid biosynthesis. In the presence of methane, all prominent lipids carried a dual isotopic signal indicative of their origin from primarily autotrophic microbes. In the absence of methane, archaeal lipid production ceased and bacterial lipid production dropped by 90%; the lipids produced by the residual fraction of the metabolically active bacterial community predominantly carried a heterotrophic signal. Collectively our results strongly suggest that the studied ANME-1 archaea oxidize methane but assimilate inorganic carbon and should thus be classified as methane-oxidizing chemoorganoautotrophs.     

Exhaled Nitric Oxide: A Novel Biomarker of Adverse Respiratory Health Effects in Epidemiological Studies

The sampling of exhaled breath is a noninvasive procedure that can be performed easily in adults, children, and patients with respiratory disease. Several studies have demonstrated increased exhaled nitric oxide in patients with pulmonary disease, including asthma. In addition, exhaled nitric oxide may be an elegant tool for monitoring of environmental health effects of air pollution and the prevalence of atopy in epidemiological surveys. Recent literature about exhaled nitric oxide is presented in this article. Technical, physiological, and behavioral confounding factors of exhaled nitric oxide measurement are outlined.     

Metabolomic Study of Biochemical Changes related to toxicity induced by bupleurotoxin Using LC-MSCoupled with a Pattern Recognition Approach

The purpose of this study was to detect changes in urine of mice and to clarify the toxicity induced by bupleurotoxin (BETX) using liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS). A procedure for urine analysis using pattern recognition was proposed to evaluate the toxicity induced by BETX in male BALB/c mice. BETX at 2.5 mg/kg was administered intraperitoneally (i.p.), and urine samples for the metabolomic study were collected from control and BETX experimental groups. Changes in the concentrations of some urine metabolites were detected exclusively in the experimental group. All results suggested that exposure to BETX might cause a disturbance in fatty acid metabolism and the oxidative stress system. These results may not only clarify the underlying mechanism of diverse intoxication effects of BETX but also provide the guidance in preclinical toxicity screening for new drugs.     

The increasing clinical relevance of human papillomavirus type 16 (HPV-16) infection in oropharyngeal cancer

Human papillomavirus type 16 (HPV-16) has been established beyond doubt as a causative agent in oropharyngeal squamous cell carcinoma (SCC). The incidence of oropharyngeal cancer has risen in recent decades, as has the proportion of patients who have a biologically relevant HPV-16 infection. Combined data from 14 recently published studies (2006-2010) show that 57% of 1316 reported cases of oropharyngeal SCC were HPV-16 positive. They had significantly better prognosis (hazard ratio (HR) for 5-year overall survival range 0.05-0.64), although smoking and higher T stage often appear as confounding factors to this favourable prognostic benefit. HPV-16 therefore has increasing importance as a clinically useful prognostic biomarker, but a benefit in survival has been seen in the use of surgery, radiotherapy, and chemotherapy, so specific changes in the preferred methods of treatment are hard to justify. Future trials that include oropharyngeal SCC will consider HPV-16 routinely as a stratification factor, and its use as a predictive biomarker awaits the development of effective targeted treatments. The undeniable and impressive prognostic significance of HPV-16 should hasten its addition to standard pathological reporting of oropharyngeal SCC, and ultimately to its inclusion in TNM staging systems of the American Joint Committee on Cancer (AJCC) and the International Union against Cancer (UICC).     

Stage-specific prognostic biomarkers in melanoma

The melanoma staging system proposed by the American Joint Committee on Cancer (AJCC) (which classifies melanoma patients into four clinical stages) is currently the most widely used tool for melanoma prognostication, and clinical management decision making by clinicians. However, multiple studies have shown that melanomas within specific AJCC Stages can exhibit varying progression and clinical outcomes. Thus, additional information, such as that provided by biomarkers is needed to assist in identifying the patients at risk of disease progression.Having previously found six independent prognostic biomarkers in melanoma, including BRAF, MMP2, p27, Dicer, Fbw7 and Tip60, our group has gone on to investigate if these markers are useful in risk stratification of melanoma patients in individual AJCC stages. First, we performed Kaplan-Meier survival and Cox proportional multivariate analyses comparing prognostication power of these markers in 254 melanoma patients for whom the expression levels were known, identifying the best performing markers as candidates for stage-specific melanoma markers. We then verified the results by incorporating an additional independent cohort (87 patients) and in a combined cohort (341 patients).Our data indicate that BRAF and MMP2 are optimal prognostic biomarkers for AJCC Stages I and II, respectively (P = 0.010, 0.000, Log-rank test); whereas p27 emerged as a good marker for AJCC Stages III/IV (0.018, 0.046, respectively, log-rank test). Thus, our study has identified stage-specific biomarkers in melanoma, a finding which may assist clinicians in designing improved personalized therapeutic modalities.     

Hyperuricemia predicts adverse clinical outcomes after cardiac resynchronization therapy

Abstract

Objectives: Changes in the levels of serum creatinine and N-terminal of prohormone brain natriuretic peptide (NT-proBNP) are useful risk markers after cardiac resynchronization therapy (CRT). The diagnostic value of changes in serum uric acid levels has been established in chronic heart failure, but no data are available on the prognostic value of hyperuricemia in a CRT population. Design: We measured markers of renal function [creatinine, blood urea nitrogen (BUN) and uric acid] and NT-proBNP levels of 129 heart failure patients undergoing CRT in a prospective, observational study. The 5-year all-cause mortality and the 6-month clinical response (≥ 15% increase in the left ventricular ejection fraction) were considered as study end points. Results: In multivariable analyses, the uric acid was found to be a statistically significant predictor of the outcome. Uric acid levels exceeding 386?mmol/L before CRT increased the chances of mortality [n?=?55, hazard ratio?=?2.39 (1.30-4.39), p?<?0.01] and poor clinical response [n?=?37, odds ratio?=?2.89 (1.22-6.87), p?=?0.01] independently of serum NT-proBNP and other factors. Conclusions: Elevated uric acid concentrations in patients with CRT are associated with an increased risk of mortality and poor clinical response independently of the NT-proBNP levels and other relevant clinical factors.     

Diagnostic mesothelioma biomarkers in effusion cytology

Malignant mesothelioma is a rare malignancy with a poor prognosis whose development is related to asbestos fiber exposure. An increasing role of genetic predisposition has been recognized recently. Pleural biopsy is the gold standard for diagnosis, in which the identification of pleural invasion by atypical mesothelial cell is a major criterion. Pleural effusion is usually the first sign of disease; therefore, a cytological specimen is often the initial or the only specimen available for diagnosis. Given that reactive mesothelial cells may show marked atypia, the diagnosis of mesothelioma on cytomorphology alone is challenging. Accordingly, cell block preparation is encouraged, as it permits immunohistochemical staining. Traditional markers of mesothelioma such as glucose transporter 1 (GLUT1) and insulin-like growth factor 2 mRNA-binding protein 3 (IMP3) are informative, but difficult to interpret when reactive proliferations aberrantly stain positive. BRCA1-associated protein 1 (BAP1) nuclear staining loss is highly specific for mesothelioma, but sensitivity is low in sarcomatoid tumors. Cyclin-dependent kinase inhibitor 2A (CDKN2A)/p16 homozygous deletion, assessed by fluorescence in situ hybridization, is more specific for mesothelioma with better sensitivity, even in the sarcomatoid variant. The surrogate marker methylthioadenosine phosphorylase (MTAP) has been found to demonstrate excellent diagnostic correlation with p16. The purpose of this review is to provide an essential appraisal of the literature regarding the diagnostic value of many of these emerging biomarkers for malignant mesothelioma in effusion cytology.     

Circulating YKL‐40 in myelofibrosis a potential novel biomarker of disease activity and the inflammatory state

Chronic myeloproliferative neoplasms (MPN), encompassing essential thrombocythaemia (ET), polycythaemia vera (PV) and myelofibrosis (PMF), are featured by a chronic inflammatory state which is pronounced in myelofibrosis The value of YKL‐40 as a biomarker of disease burden has been demonstrated in several different diseases, including cancer, diabetes mellitus and cardiovascular diseases. A state of chronic inflammation is shared by them all, YKL‐40 also being involved in the severity of chronic endothelial inflammation, which today is considered of crucial importance for the development of atherosclerosis. The MPNs being cancers with a heavy burden of cardiovascular diseases we hypothesised that circulating YKL‐40 might reflect the inflammatory process and potentially serve as a novel disease marker. Using ELISA, we measured YKL‐40 in 15 patients with ET, 16 patients with PV, 17 patients with PMF and 30 healthy controls. YKL‐40 was significantly elevated in PMF vs. control subjects, PMF levels median 43 ng/mL vs. controls median 28 ng/mL, P = 0.033. An increase from ET over PV may reflect the integrated impact of disease processes in MPNs.