Literature Watch
Metformin use and gynecological cancers: A novel treatment option emerging from drug repositioning.
Metformin use and gynecological cancers: A novel treatment option emerging from drug repositioning.
Crit Rev Oncol Hematol. 2016 Jun 18;
Authors: Gadducci A, Biglia N, Tana R, Cosio S, Gallo M
Abstract
Metformin exerts antitumor effects mainly through AMP-activated protein kinase [AMPK] activation and phosphatidylinositol 3-kinase [PI3K]-Akt-mammalian target of rapamycin [mTOR] inhibition. This drug leads to activation of the cellular energy-sensing liver kinase B1 [LKB1]/AMPK pathway. LKB1 is implicated as a tumor suppressor gene in molecular pathogenesis of different malignancies. AMPK is a serine/threonine protein kinase that acts as an ultra-sensitive cellular energy sensor maintaining the energy balance within the cell. AMPK activation inhibits mRNA translation and proliferation in cancer cells via down-regulation of PI3K/Akt/mTOR pathway. Moreover, metformin decreases the production of insulin, insulin-like growth factor, inflammatory cytokines and vascular endothelial growth factor, and therefore it exerts anti-mitotic, anti-inflammatory and anti-angiogenetic effects. Recent in vitro and experimental data suggest that metformin electively targets cancer stem cells, and acts together with chemotherapy to block tumor growth in different cancers. Several epidemiological studies and meta-analysis have shown that metformin use is associated with decreased cancer risk and/or reduced cancer mortality for different malignancies. The present review analyzes the recent biological and clinical data suggesting a possible growth-static effect of metformin also in gynecological cancers. The large majority of available clinical data on the anti-cancer potential of metformin are based on observational studies. Therefore long-term phase II-III clinical trials are strongly warranted to further investigate metformin activity in gynecological cancers.
PMID: 27378194 [PubMed - as supplied by publisher]
Clinical Characteristics of Patients With Double-Seronegative Myasthenia Gravis and Antibodies to Cortactin.
Clinical Characteristics of Patients With Double-Seronegative Myasthenia Gravis and Antibodies to Cortactin.
JAMA Neurol. 2016 Jul 5;
Authors: Cortés-Vicente E, Gallardo E, Martínez MÁ, Díaz-Manera J, Querol L, Rojas-García R, Illa I
Abstract
Importance: Double-seronegative myasthenia gravis (dSNMG) includes patients with myasthenia gravis (MG) without detectable antibodies to the nicotinic acetylcholine receptor (AChR) or to muscle-specific tyrosine kinase (MuSK). The lack of a biomarker hinders the diagnosis and clinical management in these patients. Cortactin, a protein acting downstream from agrin/low-density lipoprotein receptor-related protein 4 (LRP4)/MuSK, has been described as an antigen in dSNMG.
Objective: To describe the frequency and clinical features of patients with dSNMG who have cortactin antibodies.
Design, Setting, and Participants: A retrospective cross-sectional study was conducted at Hospital de la Santa Creu i Sant Pau, an institutional practice referral center in Barcelona, Spain, between May 1, 2015, and November 30, 2015. We included 250 patients with a definitive diagnosis of MG with available serum samples at the time of diagnosis. Descriptive and comparative data analyses were performed.
Exposures: Cortactin antibodies were measured by enzyme-linked immunosorbent assay and Western blot; AChR, MuSK, and anti-striated muscle antibodies were detected using a standard method; and LRP4 antibodies were tested using a cell-based assay.
Main Outcomes and Measures: The primary outcome was the frequency of patients with dSNMG who have cortactin antibodies. Secondary outcomes were demographic, clinical, neurophysiological, and laboratory data.
Results: Of 250 patients (mean [SD] age at onset, 49.7 [21.2] years; 56% female), 38 (15.2%) had dSNMG, 201 (80.4%) had MG with AChR antibodies, and 11 (4.4%) had MG with MuSK antibodies. Cortactin antibodies were identified in 28 patients with MG: 9 of 38 (23.7%) who had dSNMG, 19 of 201 (9.5%) who had MG with AChR antibodies (significantly lower than those with dSNMG: 9.5% vs 23.7%; P = .02), and 0 of 11 who had MG with MuSK antibodies; 0 of 29 controls had cortactin antibodies. At onset, among the 9 patients with dSNMG and cortactin antibodies, 6 had ocular MG and 3 had Myasthenia Gravis Foundation of America clinical classification IIA. Two patients with ocular MG developed generalized MG. The group with dSNMG and cortactin antibodies, compared with those who had MG with AChR antibodies, more frequently had mild forms at onset (100.0% vs 62.7%; P = .03), had fewer bulbar signs at maximal worsening (0% vs 41.3%; P = .01), and were younger at onset (median [interquartile range], 34.9 [9.5] vs 53.9 [38.5] years; P = .03); the group with dSNMG and cortactin antibodies also more frequently had ocular MG at onset than those with MG and AChR antibodies, although the difference was not statistically significant (66.7% vs 40.8%; P = .17). Of 17 patients with ocular dSNMG, 4 (23.5%) had antibodies to cortactin.
Conclusions and Relevance: In this study, patients with cortactin antibodies and dSNMG had an ocular or mild generalized phenotype of MG. Including the detection of cortactin antibodies in the routine diagnosis of dSNMG may be helpful in ocular MG.
PMID: 27379450 [PubMed - as supplied by publisher]
[Spanish patients with central hypoventilation syndrome included in the European Registry. The 2015 data].
[Spanish patients with central hypoventilation syndrome included in the European Registry. The 2015 data].
An Pediatr (Barc). 2016 Jul 1;
Authors: García Teresa MA, Porto Abal R, Rodríguez Torres S, García Urabayen D, García Martínez S, Trang H, Campos Barros A, Grupo Español de Trabajo del SHCC, Llorente de la Fuente A, Hernández González A, Bustinza Arriortua A, de la Cruz Moreno J, Pons Odena M, Ventura Faci P, Rubio Ortega L, Pérez Ruiz E, Aguilar Fernández A, Pérez Ocón A, Osona B, Delgado Pecellin I, Arroyo Carrera I, Sayas Catalán J, González Salas E, de Vicente CM
Abstract
INTRODUCTION: Congenital Central Hypoventilation Syndrome (CCHS) is a very rare genetic disease. In 2012 the European Central Hypoventilation Syndrome (EuCHS) Consortium created an online patient registry in order to improve care.
AIM: To determine the characteristics and outcomes of Spanish patients with CCHS, and detect clinical areas for improvement.
MATERIALS AND METHOD: An assessment was made on the data from Spanish patients in the European Registry, updated on December 2015.
RESULTS: The Registry contained 38 patients, born between 1987 and 2013, in 18 hospitals. Thirteen (34.2%) were older than 18 years. Three patients had died. Genetic analysis identified PHOX2B mutations in 32 (86.5%) out of 37 patients assessed. The 20/25, 20/26 and 20/27 polyalanine repeat mutations (PARMs) represented 84.3% of all mutations. Longer PARMs had more, as well as more severe, autonomic dysfunctions. Eye diseases were present in 47%, with 16% having Hirschsprung disease, 13% with hypoglycaemia, and 5% with tumours. Thirty patients (79%) required ventilation from the neonatal period onwards, and 8 (21%) later on in life (late onset/presentation). Eight children (21%) were using mask ventilation at the first home discharge. Five of them were infants with neonatal onset, two of them, both having a severe mutation, were switched to tracheostomy after cardiorespiratory arrest at home. Approximately one-third (34.3%) of patients were de-cannulated and switched to mask ventilation at a mean age of 13.7 years. Educational reinforcement was required in 29.4% of children attending school.
CONCLUSION: The implementation of the EuCHS Registry in Spain has identified some relevant issues for optimising healthcare, such as the importance of genetic study for diagnosis and assessment of severity, the high frequency of eye disease and educational reinforcement, as well as some limitations in ventilatory techniques.
PMID: 27377324 [PubMed - as supplied by publisher]
Effect of ABCB1 diplotype on tacrolimus disposition in renal recipients depends on CYP3A5 and CYP3A4 genotype.
Effect of ABCB1 diplotype on tacrolimus disposition in renal recipients depends on CYP3A5 and CYP3A4 genotype.
Pharmacogenomics J. 2016 Jul 5;
Authors: Vanhove T, Annaert P, Lambrechts D, Kuypers DR
Abstract
The relevance of most genetic polymorphisms beyond CYP3A5*1 on tacrolimus disposition remains unclear. We constructed a predictive mixed model for tacrolimus dose-corrected trough concentration (C0/dose) at months 3, 12 and 24 after transplantation in a retrospective cohort of 766 predominantly Causasian adult renal recipients (n=2042 trough concentrations). All patients were genotyped for 32 single-nucleotide polymorphisms with a proven or possible relevance to tacrolimus disposition based on the previous studies. Of these, ABCB1, ABCC2, OATP1B1, COMT, FMO, PPARA and APOA5 were analyzed as (functional) diplotype groups. Predictors of C0/dose were CYP3A5*1, hematocrit, age, CYP3A4*22, use of concomitant CYP3A4 inhibitor or inducer, ALT, estimated glomerular filtration rate, tacrolimus formulation (once vs twice daily), ABCB1 diplotype and time after transplantation. The effect of ABCB1 diplotype was small but strongly accentuated in CYP3A4*22 carriers and non-existent in CYP3A5 expressors. ABCC2 diplotype had a limited effect on C0/dose that was only statistically significant in CYP3A5 non-expressors.The Pharmacogenomics Journal advance online publication, 5 July 2016; doi:10.1038/tpj.2016.49.
PMID: 27378609 [PubMed - as supplied by publisher]
Immunoglobulin G fragment C receptor polymorphisms and efficacy of preoperative chemotherapy plus trastuzumab and lapatinib in HER2-positive breast cancer.
Immunoglobulin G fragment C receptor polymorphisms and efficacy of preoperative chemotherapy plus trastuzumab and lapatinib in HER2-positive breast cancer.
Pharmacogenomics J. 2016 Jul 5;
Authors: Musolino A, Naldi N, Dieci MV, Zanoni D, Rimanti A, Boggiani D, Sgargi P, Generali DG, Piacentini F, Ambroggi M, Cagossi K, Gianni L, Sarti S, Bisagni G, Ardizzoni A, Conte PF, Guarneri V
Abstract
Lapatinib enhances antibody-dependent cell-mediated cytotoxicity (ADCC) activity of trastuzumab. FcγR polymorphisms have been associated with both ADCC and clinical activity of trastuzumab in HER2+ breast cancer (BC) patients (pts). We analyzed FcγRIIa-H131R and FcγRIIIa-V158F polymorphisms in the CHER-LOB trial population of HER2+ BCs treated with preoperative chemotherapy plus trastuzumab (arm A), lapatinib (arm B) or both (arm C). Genotyping was successfully performed in 73/121 (60%) pts. A significant improvement in pathological complete response (pCR) rate was observed for the combination arm C, but only in FcγRIIIa V allele carriers (C vs A, 67 vs 27%, P=0.043; C vs B, 67 vs 22%, P=0.012). An independent interaction between arm C and FcγRIIIa V allele was found for pCR (odds ratio=9.4; 95% confidence interval, 2.3-39.6; P=0.003). No significant associations were observed between pCR and FcγRIIa polymorphism, and between pre-treatment tumor-infiltrating lymphocytes and FcγR polymorphisms. Our study provides evidence for a FcγRIIIa V allele-restricted pCR benefit from neoadjuvant trastuzumab plus lapatinib in HER2+ BC.The Pharmacogenomics Journal advance online publication, 5 July 2016; doi:10.1038/tpj.2016.51.
PMID: 27378608 [PubMed - as supplied by publisher]
Pharmacogenomic and personalized approaches to tackle the nonalcoholic fatty liver disease.
Pharmacogenomic and personalized approaches to tackle the nonalcoholic fatty liver disease.
Pharmacogenomics. 2016 Jul 5;
Authors: Lorbek G, Urlep Ž, Rozman D
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a raising liver disease with increasing prevalence due to the epidemics of obesity and diabetes, with end points in cirrhosis or hepatocellular carcinoma. A multitude of genetic and metabolic perturbations, together with environmental factors, likely drive the disease. However, to date only a few genes, primarily PNPLA3 and TM6SF2, associate with NAFLD and there is no specific treatment. In this review we focus on the therapeutical aspects of NAFLD, taking into account drugs and lifestyle interventions. Sex also influences disease progression and treatment outcomes. Lastly, we discuss the present and potential future of personalized approaches to tackle NAFLD and how the known polymorphisms of NAFLD associated genes influence the choice and success of therapy.
PMID: 27377717 [PubMed - as supplied by publisher]
Developing Treatments for Stimulant Abuse: A Brief Overview.
Developing Treatments for Stimulant Abuse: A Brief Overview.
East Asian Arch Psychiatry. 2016 Jun;26(2):52-9
Authors: Davidson C
Abstract
The abuse of stimulants such as cocaine, amphetamine, and methamphetamine is a huge problem in many parts of the world. Abuse of these drugs does not ruin just the user's life, but also adversely affects those around them. Despite many years of research, there are no approved medications for stimulant dependence, and treatment is focused on psychotherapy and abstinence. Over the last 10 to 20 years, there have been some major changes in approach to medication development for stimulant dependence. These include assessing ligands for non-dopaminergic sites, atypical dopamine transporter ligands, blocking long-term potentiation and / or memory reconsolidation, vaccines against the stimulant, and molecular approaches including pharmacogenomics and gene silencing. Also included in this overview are non-drug treatments such as deep brain stimulation and psychosurgery. This overview highlights recent preclinical and clinical studies of treatment development for stimulant dependence.
PMID: 27377486 [PubMed - as supplied by publisher]
Synthetic Cystic Fibrosis Sputum Medium Regulates Flagellar Biosynthesis through the flhF Gene in Burkholderia cenocepacia.
Synthetic Cystic Fibrosis Sputum Medium Regulates Flagellar Biosynthesis through the flhF Gene in Burkholderia cenocepacia.
Front Cell Infect Microbiol. 2016;6:65
Authors: Kumar B, Cardona ST
Abstract
Burkholderia cenocepacia belongs to the Burkholderia cepacia complex (Bcc), a group of at least 18 distinct species that establish chronic infections in the lung of people with the genetic disease cystic fibrosis (CF). The sputum of CF patients is rich in amino acids and was previously shown to increase flagellar gene expression in B. cenocepacia. We examined flagellin expression and flagellar morphology of B. cenocepacia grown in synthetic cystic fibrosis sputum medium (SCFM) compared to minimal medium. We found that CF nutritional conditions induce increased motility and flagellin expression. Individual amino acids added at the same concentrations as found in SCFM also increased motility but not flagellin expression, suggesting a chemotactic effect of amino acids. Electron microscopy and flagella staining demonstrated that the increase in flagellin corresponds to a change in the number of flagella per cell. In minimal medium, the ratio of multiple: single: aflagellated cells was 2:3.5:4.5; while under SCFM conditions, the ratio was 7:2:1. We created a deletion mutant, ΔflhF, to study whether this putative GTPase regulates the flagellation pattern of B. cenocepacia K56-2 during growth in CF conditions. The ΔflhF mutant exhibited 80% aflagellated, 14% single and 6% multiple flagellated bacterial subpopulations. Moreover, the ratio of multiple to single flagella in WT and ΔflhF was 3.5 and 0.43, respectively in CF conditions. The observed differences suggest that FlhF positively regulates flagellin expression and the flagellation pattern in B. cenocepacia K56-2 during CF nutritional conditions.
PMID: 27379216 [PubMed - as supplied by publisher]
Active cycle of breathing technique for cystic fibrosis.
Active cycle of breathing technique for cystic fibrosis.
Cochrane Database Syst Rev. 2016 Jul 5;7:CD007862
Authors: Mckoy NA, Wilson LM, Saldanha IJ, Odelola OA, Robinson KA
Abstract
BACKGROUND: People with cystic fibrosis experience chronic airway infections as a result of mucus build up within the lungs. Repeated infections often cause lung damage and disease. Airway clearance therapies aim to improve mucus clearance, increase sputum production, and improve airway function. The active cycle of breathing technique (also known as ACBT) is an airway clearance method that uses a cycle of techniques to loosen airway secretions including breathing control, thoracic expansion exercises, and the forced expiration technique. This is an update of a previously published review.
OBJECTIVES: To compare the clinical effectiveness of the active cycle of breathing technique with other airway clearance therapies in cystic fibrosis.
SEARCH METHODS: We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews.Date of last search: 25 April 2016.
SELECTION CRITERIA: Randomised or quasi-randomised controlled clinical studies, including cross-over studies, comparing the active cycle of breathing technique with other airway clearance therapies in cystic fibrosis.
DATA COLLECTION AND ANALYSIS: Two review authors independently screened each article, abstracted data and assessed the risk of bias of each study.
MAIN RESULTS: Our search identified 62 studies, of which 19 (440 participants) met the inclusion criteria. Five randomised controlled studies (192 participants) were included in the meta-analysis; three were of cross-over design. The 14 remaining studies were cross-over studies with inadequate reports for complete assessment. The study size ranged from seven to 65 participants. The age of the participants ranged from six to 63 years (mean age 22.33 years). In 13 studies, follow up lasted a single day. However, there were two long-term randomised controlled studies with follow up of one to three years. Most of the studies did not report on key quality items, and therefore, have an unclear risk of bias in terms of random sequence generation, allocation concealment, and outcome assessor blinding. Due to the nature of the intervention, none of the studies blinded participants or the personnel applying the interventions. However, most of the studies reported on all planned outcomes, had adequate follow up, assessed compliance, and used an intention-to-treat analysis.Included studies compared the active cycle of breathing technique with autogenic drainage, airway oscillating devices, high frequency chest compression devices, conventional chest physiotherapy, and positive expiratory pressure. Preference of technique varied: more participants preferred autogenic drainage over the active cycle of breathing technique; more preferred the active cycle of breathing technique over airway oscillating devices; and more were comfortable with the active cycle of breathing technique versus high frequency chest compression. No significant difference was seen in quality of life, sputum weight, exercise tolerance, lung function, or oxygen saturation between the active cycle of breathing technique and autogenic drainage or between the active cycle of breathing technique and airway oscillating devices. There was no significant difference in lung function and the number of pulmonary exacerbations between the active cycle of breathing technique alone or in conjunction with conventional chest physiotherapy. All other outcomes were either not measured or had insufficient data for analysis.
AUTHORS' CONCLUSIONS: There is insufficient evidence to support or reject the use of the active cycle of breathing technique over any other airway clearance therapy. Five studies, with data from eight different comparators, found that the active cycle of breathing technique was comparable with other therapies in outcomes such as participant preference, quality of life, exercise tolerance, lung function, sputum weight, oxygen saturation, and number of pulmonary exacerbations. Longer-term studies are needed to more adequately assess the effects of the active cycle of breathing technique on outcomes important for people with cystic fibrosis such as quality of life and preference.
PMID: 27378490 [PubMed - as supplied by publisher]
Eradication of methicillin resistant Staphylococcus aureus detected for the first time in cystic fibrosis: A single center observational study.
Eradication of methicillin resistant Staphylococcus aureus detected for the first time in cystic fibrosis: A single center observational study.
Pediatr Pulmonol. 2016 Jul 5;
Authors: Kappler M, Nagel F, Feilcke M, Kröner C, Pawlita I, Naehrig S, Ripper J, Hengst M, von Both U, Forstner M, Hector A, Griese M
Abstract
OBJECTIVE: To retrospectively identify CF patients with methicillin resistant Staphylococcus aureus (MRSA) and to assess the long-term success of an eradication scheme introduced in 2002 for all newly colonized patients.
PATIENTS: All microbiological results from all 505 CF patients followed between 2002 and 2012 were analyzed focusing on the detection of MRSA.
METHODS: Retrospective patient record analysis of MRSA positive CF patients regarding eradication and clinical outcome.
RESULTS: We identified 57 patients with MRSA, mean age 15.3 years (range: 0.6-36.9, incidence 0.9%/year). Of these, nine patients were lost to follow-up; seven chronically colonized patients were excluded from the intervention. Eradication was suggested to all patients, 37/41 gave their consent to the following two-step approach: (i) dual iv antibiotic treatment over 3 weeks, accompanied by hygienic directives and topical therapy for 5 days followed by a 6-week period with dual oral antibiotic therapy and inhalation with vancomycin. (ii) Each new MRSA detection was treated with 6 weeks inhalation of vancomycin and topical therapy for 5 days. Long-term eradication was rated by the microbiological status in the third year after first detection. MRSA was eradicated in 31 of 37 patients (84%) whose clinical course was stable (mean FEV1 one year before MRSA 80.4%, 3 years after MRSA 81.0%).
CONCLUSIONS: MRSA colonization mandates complex and expensive hygienic measures which are not well accepted by patients. Therefore, MRSA eradication is desirable. Intensive therapy regimens may be successful in patients with CF and might help to maintain a stable clinical course. Pediatr Pulmonol. © 2016 Wiley Periodicals, Inc.
PMID: 27378061 [PubMed - as supplied by publisher]
Colonization of CF patients' upper airways with S. aureus contributes more decisively to upper airway inflammation than P. aeruginosa.
Colonization of CF patients' upper airways with S. aureus contributes more decisively to upper airway inflammation than P. aeruginosa.
Med Microbiol Immunol. 2016 Jul 4;
Authors: Janhsen WK, Arnold C, Hentschel J, Lehmann T, Pfister W, Baier M, Böer K, Hünniger K, Kurzai O, Hipler UC, Mainz JG
Abstract
In cystic fibrosis (CF) patients' airways, inflammatory processes decisively contribute to remodeling and pulmonary destruction. The aims of this study were to compare upper airway (UAW) inflammation in the context of Staphylococcus aureus and Pseudomonas aeruginosa colonization in a longitudinal setting, and to examine further factors influencing UAW inflammation. Therefore, we analyzed soluble inflammatory mediators in noninvasively obtained nasal lavage (NL) of CF patients together with microbiology, medication, and relevant clinical parameters. NL, applying 10 mL of isotonic saline per nostril, was serially performed in 74 CF patients (326 samples). Concentrations of the inflammatory mediators' interleukin (IL)-1β, IL-6, IL-8, matrix metalloproteinase (MMP)-9, and its anti-protease TIMP-1 were quantified by bead-based multiplexed assay, neutrophil elastase (NE) via ELISA. Culture-based microbiology of the upper and lower airways (LAW), as well as serological and clinical findings, were compiled. Our results indicate that UAW colonization with S. aureus significantly impacts the concentration of all measured inflammatory mediators in NL fluid except TIMP-1, whereas these effects were not significant for P. aeruginosa. Patients with S. aureus colonization of both the UAW and LAW showed significantly increased concentrations of IL-1β, IL-6, IL-8, MMP-9, and slightly elevated concentrations of NE in NL fluid compared to non-colonized patients. This work elaborates a survey on S. aureus' virulence factors that may contribute to this underestimated pathology. Serial assessment of epithelial lining fluid by NL reveals that colonization of the UAW with S. aureus contributes more to CF airway inflammatory processes than hitherto expected.
PMID: 27377929 [PubMed - as supplied by publisher]
Classification of CFTR mutation classes.
Classification of CFTR mutation classes.
Lancet Respir Med. 2016 Jul 1;
Authors: Stanke F, Tümmler B
PMID: 27377412 [PubMed - as supplied by publisher]
Selection on Network Dynamics Drives Differential Rates of Protein Domain Evolution.
Selection on Network Dynamics Drives Differential Rates of Protein Domain Evolution.
PLoS Genet. 2016 Jul;12(7):e1006132
Authors: Mannakee BK, Gutenkunst RN
Abstract
The long-held principle that functionally important proteins evolve slowly has recently been challenged by studies in mice and yeast showing that the severity of a protein knockout only weakly predicts that protein's rate of evolution. However, the relevance of these studies to evolutionary changes within proteins is unknown, because amino acid substitutions, unlike knockouts, often only slightly perturb protein activity. To quantify the phenotypic effect of small biochemical perturbations, we developed an approach to use computational systems biology models to measure the influence of individual reaction rate constants on network dynamics. We show that this dynamical influence is predictive of protein domain evolutionary rate within networks in vertebrates and yeast, even after controlling for expression level and breadth, network topology, and knockout effect. Thus, our results not only demonstrate the importance of protein domain function in determining evolutionary rate, but also the power of systems biology modeling to uncover unanticipated evolutionary forces.
PMID: 27380265 [PubMed - as supplied by publisher]
Humoral Dysregulation Associated with Increased Systemic Inflammation among Injection Heroin Users.
Humoral Dysregulation Associated with Increased Systemic Inflammation among Injection Heroin Users.
PLoS One. 2016;11(7):e0158641
Authors: Piepenbrink MS, Samuel M, Zheng B, Carter B, Fucile C, Bunce C, Kiebala M, Khan AA, Thakar J, Maggirwar SB, Morse D, Rosenberg AF, Haughey NJ, Valenti W, Keefer MC, Kobie JJ
Abstract
BACKGROUND: Injection drug use is a growing major public health concern. Injection drug users (IDUs) have a higher incidence of co-morbidities including HIV, Hepatitis, and other infections. An effective humoral response is critical for optimal homeostasis and protection from infection; however, the impact of injection heroin use on humoral immunity is poorly understood. We hypothesized that IDUs have altered B cell and antibody profiles.
METHODS AND FINDINGS: A comprehensive systems biology-based cross-sectional assessment of 130 peripheral blood B cell flow cytometry- and plasma- based features was performed on HIV-/Hepatitis C-, active heroin IDUs who participated in a syringe exchange program (n = 19) and healthy control subjects (n = 19). The IDU group had substantial polydrug use, with 89% reporting cocaine injection within the preceding month. IDUs exhibited a significant, 2-fold increase in total B cells compared to healthy subjects, which was associated with increased activated B cell subsets. Although plasma total IgG titers were similar between groups, IDUs had significantly higher IgG3 and IgG4, suggestive of chronic B cell activation. Total IgM was also increased in IDUs, as well as HIV Envelope-specific IgM, suggestive of increased HIV exposure. IDUs exhibited numerous features suggestive of systemic inflammation, including significantly increased plasma sCD40L, TNF-α, TGF-α, IL-8, and ceramide metabolites. Machine learning multivariate analysis distilled a set of 10 features that classified samples based on group with absolute accuracy.
CONCLUSIONS: These results demonstrate broad alterations in the steady-state humoral profile of IDUs that are associated with increased systemic inflammation. Such dysregulation may impact the ability of IDUs to generate optimal responses to vaccination and infection, or lead to increased risk for inflammation-related co-morbidities, and should be considered when developing immune-based interventions for this growing population.
PMID: 27379802 [PubMed - as supplied by publisher]
Editorial: Protein Interaction Networks in Health and Disease.
Editorial: Protein Interaction Networks in Health and Disease.
Front Genet. 2016;7:111
Authors: Petrakis S, Andrade-Navarro MA
PMID: 27379161 [PubMed - as supplied by publisher]
Silicon: Potential to Promote Direct and Indirect Effects on Plant Defense Against Arthropod Pests in Agriculture.
Silicon: Potential to Promote Direct and Indirect Effects on Plant Defense Against Arthropod Pests in Agriculture.
Front Plant Sci. 2016;7:744
Authors: Reynolds OL, Padula MP, Zeng R, Gurr GM
Abstract
Silicon has generally not been considered essential for plant growth, although it is well recognized that many plants, particularly Poaceae, have substantial plant tissue concentrations of this element. Recently, however, the International Plant Nutrition Institute [IPNI] (2015), Georgia, USA has listed it as a "beneficial substance". This reflects that numerous studies have now established that silicon may alleviate both biotic and abiotic stress. This paper explores the existing knowledge and recent advances in elucidating the role of silicon in plant defense against biotic stress, particularly against arthropod pests in agriculture and attraction of beneficial insects. Silicon confers resistance to herbivores via two described mechanisms: physical and biochemical/molecular. Until recently, studies have mainly centered on two trophic levels; the herbivore and plant. However, several studies now describe tri-trophic effects involving silicon that operate by attracting predators or parasitoids to plants under herbivore attack. Indeed, it has been demonstrated that silicon-treated, arthropod-attacked plants display increased attractiveness to natural enemies, an effect that was reflected in elevated biological control in the field. The reported relationships between soluble silicon and the jasmonic acid (JA) defense pathway, and JA and herbivore-induced plant volatiles (HIPVs) suggest that soluble silicon may enhance the production of HIPVs. Further, it is feasible that silicon uptake may affect protein expression (or modify proteins structurally) so that they can produce additional, or modify, the HIPV profile of plants. Ultimately, understanding silicon under plant ecological, physiological, biochemical, and molecular contexts will assist in fully elucidating the mechanisms behind silicon and plant response to biotic stress at both the bi- and tri-trophic levels.
PMID: 27379104 [PubMed - as supplied by publisher]
AMIGO2, a toolbox for dynamic modeling, optimization and control in systems biology.
AMIGO2, a toolbox for dynamic modeling, optimization and control in systems biology.
Bioinformatics. 2016 Jul 4;
Authors: Balsa-Canto E, Henriques D, Gabor A, Banga JR
Abstract
MOTIVATION: Many problems of interest in dynamic modeling and control of biological systems can be posed as non-linear optimization problems subject to algebraic and dynamic constraints. In the context of modeling, this is the case of e.g. parameter estimation, optimal experimental design and dynamic flux balance analysis. In the context of control, model-based metabolic engineering or drug dose optimization problems can be formulated as (multi-objective) optimal control problems. Finding a solution to those problems is a very challenging task which requires advanced numerical methods.
RESULTS: This work presents the AMIGO2 toolbox: the first multiplatform software tool that automatizes the solution of all those problems, offering a suite of state-of-the-art (multi-objective) global optimizers and advanced simulation approaches.
AVAILABILITY: The toolbox and its documentation are available at: sites.google.com/site/amigo2toolbox CONTACT: ebalsa@iim.csic.es.
PMID: 27378288 [PubMed - as supplied by publisher]
Comparative genomic analysis of novel Acinetobacter symbionts: A combined systems biology and genomics approach.
Comparative genomic analysis of novel Acinetobacter symbionts: A combined systems biology and genomics approach.
Sci Rep. 2016;6:29043
Authors: Gupta V, Haider S, Sood U, Gilbert JA, Ramjee M, Forbes K, Singh Y, Lopes BS, Lal R
Abstract
The increasing trend of antibiotic resistance in Acinetobacter drastically limits the range of therapeutic agents required to treat multidrug resistant (MDR) infections. This study focused on analysis of novel Acinetobacter strains using a genomics and systems biology approach. Here we used a network theory method for pathogenic and non-pathogenic Acinetobacter spp. to identify the key regulatory proteins (hubs) in each strain. We identified nine key regulatory proteins, guaA, guaB, rpsB, rpsI, rpsL, rpsE, rpsC, rplM and trmD, which have functional roles as hubs in a hierarchical scale-free fractal protein-protein interaction network. Two key hubs (guaA and guaB) were important for insect-associated strains, and comparative analysis identified guaA as more important than guaB due to its role in effective module regulation. rpsI played a significant role in all the novel strains, while rplM was unique to sheep-associated strains. rpsM, rpsB and rpsI were involved in the regulation of overall network topology across all Acinetobacter strains analyzed in this study. Future analysis will investigate whether these hubs are useful as drug targets for treating Acinetobacter infections.
PMID: 27378055 [PubMed - as supplied by publisher]
CO2-evoked release of PGE2 modulates sighs and inspiration as demonstrated in brainstem organotypic culture.
CO2-evoked release of PGE2 modulates sighs and inspiration as demonstrated in brainstem organotypic culture.
Elife. 2016 Jul 5;5
Authors: Forsberg D, Horn Z, Tserga E, Smedler E, Silberberg G, Shvarev Y, Kaila K, Uhlén P, Herlenius E
Abstract
Inflammation-induced release of prostaglandin E2 (PGE2) changes breathing patterns and the response to CO2 levels. This may have fatal consequences in newborn babies and result in sudden infant death. To elucidate the underlying mechanisms, we present a novel breathing brainstem organotypic culture that generates rhythmic neural network and motor activity for 3 weeks. We show that increased CO2 elicits a gap junction-dependent release of PGE2. This alters neural network activity in the preBötzinger rhythm-generating complex and in the chemosensitive brainstem respiratory regions, thereby increasing sigh frequency and the depth of inspiration. We used mice lacking eicosanoid prostanoid 3 receptors (EP3R), breathing brainstem organotypic slices and optogenetic inhibition of EP3R(+/+)cells to demonstrate that the EP3R is important for the ventilatory response to hypercapnia. Our study identifies a novel pathway linking the inflammatory and respiratory systems, with implications for inspiration and sighs throughout life, and the ability to autoresuscitate when breathing fails.
PMID: 27377173 [PubMed - as supplied by publisher]
Piecewise linear approximations to model the dynamics of adaptation to osmotic stress by food-borne pathogens.
Piecewise linear approximations to model the dynamics of adaptation to osmotic stress by food-borne pathogens.
Int J Food Microbiol. 2016 Jun 22;
Authors: Métris A, George SM, Ropers D
Abstract
Addition of salt to food is one of the most ancient and most common methods of food preservation. However, little is known of how bacterial cells adapt to such conditions. We propose to use piecewise linear approximations to model the regulatory adaptation of Escherichiacoli to osmotic stress. We apply the method to eight selected genes representing the functions known to be at play during osmotic adaptation. The network is centred on the general stress response factor, sigma S, and also includes a module representing the catabolic repressor CRP-cAMP. Glutamate, potassium and supercoiling are combined to represent the intracellular regulatory signal during osmotic stress induced by salt. The output is a module where growth is represented by the concentration of stable RNAs and the transcription of the osmotic gene osmY. The time course of gene expression of transport of osmoprotectant represented by the symporter proP and of the osmY is successfully reproduced by the network. The behaviour of the rpoS mutant predicted by the model is in agreement with experimental data. We discuss the application of the model to food-borne pathogens such as Salmonella; although the genes considered have orthologs, it seems that supercoiling is not regulated in the same way. The model is limited to a few selected genes, but the regulatory interactions are numerous and span different time scales. In addition, they seem to be condition specific: the links that are important during the transition from exponential to stationary phase are not all needed during osmotic stress. This model is one of the first steps towards modelling adaptation to stress in food safety and has scope to be extended to other genes and pathways, other stresses relevant to the food industry, and food-borne pathogens. The method offers a good compromise between systems of ordinary differential equations, which would be unmanageable because of the size of the system and for which insufficient data are available, and the more abstract Boolean methods.
PMID: 27377009 [PubMed - as supplied by publisher]
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