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1.
Ambio ; 53(7): 1015-1036, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38613747

ABSTRACT

The sustainability of social-ecological systems within river deltas globally is in question as rapid development and environmental change trigger "negative" or "positive" tipping points depending on actors' perspectives, e.g. regime shift from abundant sediment deposition to sediment shortage, agricultural sustainability to agricultural collapse or shift from rural to urban land use. Using a systematic review of the literature, we show how cascading effects across anthropogenic, ecological, and geophysical processes have triggered numerous tipping points in the governance, hydrological, and land-use management of the world's river deltas. Crossing tipping points had both positive and negative effects that generally enhanced economic development to the detriment of the environment. Assessment of deltas that featured prominently in the review revealed how outcomes of tipping points can inform the long-term trajectory of deltas towards sustainability or collapse. Management of key drivers at the delta scale can trigger positive tipping points to place social-ecological systems on a pathway towards sustainable development.


Subject(s)
Conservation of Natural Resources , Rivers , Agriculture , Ecosystem , Sustainable Development
2.
J Mol Model ; 28(10): 305, 2022 Sep 08.
Article in English | MEDLINE | ID: mdl-36074206

ABSTRACT

The pandemic of COVID-19 severe acute respiratory syndrome, which was fatal for millions of people worldwide, triggered the race to understand in detail the molecular mechanisms of this disease. In this work, the differences of interactions between the SARS-CoV/SARS-CoV-2 Receptor binding domain (RBD) and the human Angiotensin Converting Enzyme 2 (ACE2) receptor were studied using in silico tools. Our results show that SARS-CoV-2 RBD is more stable and forms more interactions with ACE2 than SARS-CoV. At its interface, three stable binding patterns are observed and named red-K31, green-K353 and blue-M82 according to the central ACE2 binding residue. In SARS-CoV instead, only the first two binding patches are persistently formed during the MD simulation. Our MM/GBSA calculations indicate the binding free energy difference of about 2.5 kcal/mol between SARS-CoV-2 and SARS-CoV which is compatible with the experiments. The binding free energy decomposition points out that SARS-CoV-2 RBD-ACE2 interactions of the red-K31 ([Formula: see text]) and blue-M82 ([Formula: see text]) patterns contribute more to the binding affinity than in SARS-CoV ([Formula: see text] for red-K31), while the contribution of the green-K353 pattern is very similar in the two strains ([Formula: see text] and [Formula: see text] for SARS-CoV-2 and SARS-CoV, respectively). Five groups of mutations draw our attention at the RBD-ACE2 binding interface, among them, the mutation -PPA469-471/GVEG482-485 has the most important and favorable impact on SARS-CoV-2 binding to the ACE2 receptor. These results, highlighting the molecular differences in the binding between the two viruses, contribute to the common knowledge about the new corona virus and to the development of appropriate antiviral treatments, addressing the necessity of ongoing pandemics.


Subject(s)
COVID-19 , Severe acute respiratory syndrome-related coronavirus , Angiotensin-Converting Enzyme 2 , Binding Sites , Humans , Molecular Dynamics Simulation , Peptidyl-Dipeptidase A/metabolism , Protein Binding , Severe acute respiratory syndrome-related coronavirus/metabolism , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism
3.
Clin Immunol ; 237: 108980, 2022 04.
Article in English | MEDLINE | ID: mdl-35296428

ABSTRACT

Neuropsychiatric systemic lupus erythematosus (NPSLE) varies in presentation and is one of the leading causes of morbidity and mortality among patients with SLE. This study determined the most critical serum biomarkers for the development of NPSLE as they may have clinical utility prior to the onset of neuropsychiatric symptoms. We retrospectively analyzed 35 NPSLE patients, 34 SLE patients, 20 viral meningitis (VM) patients, and 16 relapsing-remitting multiple sclerosis (MS) patients. We measured anti-suprabasin antibodies concentrations in serum by using Luciferase immunoprecipitation system (LIPS) assay. The serum concentrations of cytokines/chemokines were measured by using multiplex bead-based assay. We found serum FGF-2 level was significantly higher in the NPSLE group compared to the SLE group and the healthy control group. The anti-suprabasin antibody relative concentration (SRC) has high positive predictive values for the development of NPSLE. The most essential biomarkers are VEGF, anti-suprabasin antibodies, sCD40L, IL-10, GRO, MDC, IL-8, IL-9, TNF-α, MIP-1α.


Subject(s)
Lupus Erythematosus, Systemic , Lupus Vasculitis, Central Nervous System , Biomarkers , Chemokines , Cytokines , Humans , Lupus Vasculitis, Central Nervous System/diagnosis , Retrospective Studies
4.
J Clin Gastroenterol ; 55(4): 316-320, 2021 04 01.
Article in English | MEDLINE | ID: mdl-32694265

ABSTRACT

BACKGROUND: Short meal-to-bed time (MTBT) has been reported to relate to gastroesophageal reflux disease (GERD), but evidence is lacking in pregnant women. We aimed to assess the characteristics of GERD and the association between MTBT and GERD during pregnancy. PATIENTS AND METHODS: A cross-sectional study was carried out on 400 pregnant women aged 18 years and older visiting the antenatal clinic of Gia-Dinh People's Hospital, Vietnam. GERD was defined as having troublesome heartburn and/or regurgitation at least once a week. Reflux-related insomnia was defined as having difficulties in initiating or maintaining sleep through the night. MTBT was defined as "short" if it was ≤2 hours in more than two thirds of days in a week. RESULTS: There were 154 (38.5%) patients with GERD and 20 (13.0%) patients with reflux-related insomnia. In multivariate analysis, there were 3 factors significantly associated with GERD: third trimester [odds ratio (OR)=1.66; 95% confidence interval (CI): 1.03-2.69], previous history of typical reflux symptoms (OR=9.05; 95% CI: 5.29-15.50), and short MTBT (OR=12.73; 95% CI: 2.92-55.45). The frequency of reflux symptoms progressively increased across subgroups of patients with no short MTBT, either daytime or nighttime short MTBT, and with both daytime and nighttime short MTBT. Nighttime MTBT was also a significant risk factor for reflux-related insomnia (OR=4.60; 95% CI: 1.64-12.92). CONCLUSIONS: We reported for the first time that short MTBT was a predominant risk factor of GERD in pregnancy. This dieting habit was significantly associated with reflux symptom frequency and reflux-related insomnia.


Subject(s)
Esophagitis, Peptic , Gastroesophageal Reflux , Cross-Sectional Studies , Female , Gastroesophageal Reflux/epidemiology , Gastroesophageal Reflux/etiology , Heartburn/epidemiology , Heartburn/etiology , Humans , Pregnancy , Risk Factors , Surveys and Questionnaires
5.
J Breath Res ; 15(1): 016012, 2020 11 20.
Article in English | MEDLINE | ID: mdl-33108776

ABSTRACT

In children with asthma, the responsiveness of inhaled corticosteroids (ICS) is depended on asthma endotype and phenotype. This study aimed to describe the clinical and biological characteristics, and its correlation with polymorphism of rs28364072 in FCER2 of asthmatic children. This work aimed to study the correlation between fractional concentration of exhaled nitric oxide (FENO) level and rs28364072 polymorphism of FCER2 gene with ICS responsiveness and disease control in children with asthma. This study was a prospective and descriptive study. All clinical characteristics, FENO, blood eosinophil counts (BEC), skin prick test (SPT), total IgE, asthma control test, and FCER2 gene polymorphism were performed for each patient. One hundred and seven asthmatic children who were over 5 years old (9.2 ± 2.6), were included. Patients with FENO > 20 ppb had higher percentage of positive SPT, total IgE level, and BEC (89.2 vs 80.0%, 851.1 vs 656.9 UI ml-1, and 785 ± 576 G L-1 vs 425 ± 364 G L-1; respectively). Among them, there were 54.2% of homozygous TT, 36.4% of heterozygous TC, and 9.4% of homozygous CC of rs28364072 polymorphism in FCER2. The percentage of patients with controlled asthma was increasing after 1 month and 3 months (47.1% and 58.8%; respectively). During the study, the ICS was decreasing as indicated by asthma control (348 ± 118 mcg at 1st month vs 329 ± 119 mcg at 3rd month; p < 0.05). CC genotype had the lowest level of increasing FEV1 compared to that in genotype TC and TT (8.4% vs 8.7% and 27.1%; p > 0.05 and p < 0.05; respectively). The percentage of polymorphism in rs28364072 of FCER2 was significant higher in patients with controlled asthma compared to uncontrolled asthma. Asthmatic children with high FENO and rs28364072 polymorphism in FCER2 gene are good responders to ICS; however, asthmatic children with homozygous variant CC of rs28364072 are poorly responsive to ICS.


Subject(s)
Adrenal Cortex Hormones/administration & dosage , Asthma/drug therapy , Asthma/genetics , Breath Tests , Exhalation , Lectins, C-Type/genetics , Nitric Oxide/metabolism , Polymorphism, Single Nucleotide/genetics , Receptors, IgE/genetics , Administration, Inhalation , Adolescent , Adrenal Cortex Hormones/therapeutic use , Asthma/blood , Asthma/physiopathology , Child , Child, Preschool , Female , Humans , Immunoglobulin E/blood , Lectins, C-Type/therapeutic use , Male , Prospective Studies , Receptors, IgE/therapeutic use
6.
Int J Surg Case Rep ; 73: 285-288, 2020.
Article in English | MEDLINE | ID: mdl-32721890

ABSTRACT

INTRODUCTION: Situs inversus totalis (SIT) is an uncommon congenital condition characterized by total transposition of abdominal and thoracic viscera. Performing minimally invasive cardiac surgery on individuals with SIT requires different surgical planning because of the unfamiliar positions of the heart and great vessels. PRESENTATION OF CASE: A 52-year-old female was admitted to our center with palpitations and dyspnea on exertion. Chest X-ray showed dextrocardia. Echocardiography and chest computerized tomography (CT) revealed SIT with severe rheumatic mitral valve disease. DISCUSSION: Pre-operative three-dimensional (3D) chest CT reconstruction was helpful in surgical planning and management of cardiopulmonary bypass (CPB). Mitral valve replacement and concomitant atrial fibrillation (AF) ablation using radiofrequency (RF) energy via left mini-thoracotomy was successfully performed on the patient. CONCLUSION: Minimally invasive approach can be safely and effectively employed in patients with SIT.

7.
Biochemistry ; 59(13): 1378-1390, 2020 04 07.
Article in English | MEDLINE | ID: mdl-32043865

ABSTRACT

Zinc-finger structure, in which a Zn2+ ion binds to four cysteines or histidines in a tetrahedral structure, is a very common motif of nucleic acid-binding proteins. The corresponding interaction model is present in 3% of the genes in the human genome. As a result, the zinc finger has been extremely useful in various therapeutic and research capacities and in biotechnology. In a stable configuration of the zinc finger, the cysteine amino acids are deprotonated and become negatively charged. Thus, the Zn2+ ion is overscreened by four cysteine charges (overcharged). Whether this overcharged configuration is also stable when such a negatively charged zinc finger binds to a negatively charged DNA molecule is unknown. We investigated how the deprotonated state of cysteine influences its structure, dynamics, and function in binding to DNA molecules by using an all-atom molecular dynamics simulation up to the microsecond range of an androgen receptor protein dimer. Our results showed that the deprotonated state of cysteine residues is essential for the mechanical stabilization of the functional, folded conformation. This state stabilizes not only the protein structure but also the protein-DNA binding complex. The differences in the structural and energetic properties of the two sequence-identical monomers are also investigated and show the strong influence of DNA on the structure of the zinc-finger protein dimer upon complexation. Our result can potentially lead to a better molecular understanding of one of the most common classes of zinc fingers.


Subject(s)
DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , DNA/metabolism , Zinc/metabolism , Amino Acid Sequence , DNA/chemistry , DNA/genetics , DNA-Binding Proteins/genetics , Humans , Protein Array Analysis , Zinc/chemistry , Zinc Fingers
8.
BMJ Open ; 9(8): e028751, 2019 08 24.
Article in English | MEDLINE | ID: mdl-31446407

ABSTRACT

OBJECTIVES: With the increasing interest in personalised medicine, the use of subgroup analyses is likely to increase. Subgroup analyses are challenging and often misused, possibly leading to false interpretations of the effect. It remains unclear to what extent key organisations warn for such pitfalls and translate current methodological research to detect these effects into research guidelines. The aim of this scoping review is to determine and evaluate the current guidance used by organisations for exploring, confirming and interpreting subgroup effects. DESIGN: Scoping review. ELIGIBILITY CRITERIA: We identified four types of key stakeholder organisations: industry, health technology assessment organisations (HTA), academic/non-profit research organisations and regulatory bodies. After literature search and expert consultation, we identified international and national organisations of each type. For each organisation that was identified, we searched for official research guidance documents and contacted the organisation for additional guidance. RESULTS: Twenty-seven (45%) of the 60 organisations that we included had relevant research guidance documents. We observed large differences between organisation types: 18% (n=2) of the industry organisations, 64% (n=9) of the HTA organisations, 38% (n=8) of academic/non-profit research organisations and 57% (n=8) of regulatory bodies provided guidance documents. The majority of the documents (n=33, 63%) mentioned one or more challenges in subgroup analyses, such as false positive findings or ecological bias with variations across the organisation types. Statistical recommendations were less common (n=19, 37%) and often limited to a formal test of interaction. CONCLUSIONS: Almost half of the organisations included in this scoping review provided guidance on subgroup effect research in their guidelines. However, there were large differences between organisations in the amount and level of detail of their guidance. Effort is required to translate and integrate research findings on subgroup analysis to practical guidelines for decision making and to reduce the differences between organisations and organisation types.


Subject(s)
Biomedical Research/standards , Guidelines as Topic , Precision Medicine , Academies and Institutes , Evidence-Based Medicine , Government Regulation , Health Care Sector , Humans , Organizations , Research Design , Technology Assessment, Biomedical
9.
Rev. bras. psicanál ; 52(1): 201-206, jan.-mar. 2018. ilus
Article in Portuguese | LILACS-Express | LILACS, Index Psychology - journals | ID: biblio-1288729
10.
Dalton Trans ; 46(39): 13220-13228, 2017 Oct 10.
Article in English | MEDLINE | ID: mdl-28682383

ABSTRACT

Drycast methods have been used frequently in recent decades to adsorb a range of synthetic catalysts on electrodes. The uncoordinated multilayers that are formed via this immobilization method can however have a strong impact on the electrocatalytic reaction pathway as slow electron transfer and intermolecular interactions can alter the chemistry of the catalysts on the surface. To gain insight into the structure of Fe porphyrin Hangman catalysts during electrocatalytic oxygen reduction a combination of electrochemistry and surface enhanced resonance Raman spectroscopy (SERRS) was applied. The Hangman complexes were attached to the electrodes via different methods and the influence of the immobilisation technique on oxygen chemistry was studied. In multilayer systems, new intermediates could be identified via potential dependent SERRS that were not present in solution or in monolayer systems under catalytic conditions. A comparison of Raman spectra obtained either via Soret or Q-band excitation showed that the porphyrin symmetry is strongly distorted under reducing conditions, which was interpreted by the transient formation of dimer complexes during catalysis.

11.
Eur J Pain ; 21(9): 1582-1590, 2017 10.
Article in English | MEDLINE | ID: mdl-28543929

ABSTRACT

OBJECTIVE: This study investigates the prevalence of different types of childhood adversities (CA) and posttraumatic stress disorder (PTSD) in female patients with Fibromyalgia or Chronic Widespread Pain (FM/CWP) compared to patients with Functional Dyspepsia (FD) and achalasia. In FM/CWP, we also investigated the association between CA and PTSD on the one hand and pain severity on the other. METHODS: Patient samples consisted of 154 female FM/CWP, 83 female FD and 53 female achalasia patients consecutively recruited from a tertiary care hospital. Well-validated self-report questionnaires were used to investigate CA and PTSD. RESULTS: Forty-nine per cent of FM/CWP patients reported at least 1 type of CA, compared to 39.7% of FD patients and 23.4% of achalasia patients (p < 0.01). The prevalence of CA did not differ significantly between FM/CWP and FD, but both groups had a higher prevalence of CA compared to both achalasia and healthy controls (p < 0.01). FM/CWP patients were six times more likely to report PTSD than both FD (p < 0.001) and achalasia (p < 0.001) patients. CONCLUSION: In FM/CWP, PTSD comorbidity, but not CA, was associated with self-reported pain severity and PTSD severity mediated the relationship between CA and pain severity. In summary, the prevalence of CA is higher in FM/CWP compared to achalasia, but similar to FD. However, PTSD is more prevalent in FM/CWP compared to FD and associated with higher pain intensity in FM/CWP. SIGNIFICANCE: As expected and has been shown in other functional disorders, we found elevated levels of childhood adversity in FM/CWP patients. Results of this study however suggest that the impact of childhood adversity (i.e. whether such events have led to the development of PTSD symptoms), rather than the mere presence of such adversity, is of crucial importance in FM/CWP patients. Screening for PTSD symptoms should be an essential part of the assessment process in patients suffering from FM/CWP, and both prevention and intervention efforts should take into account PTSD symptoms and their impact on pain severity and general functioning.


Subject(s)
Adult Survivors of Child Adverse Events/psychology , Chronic Pain/epidemiology , Fibromyalgia/epidemiology , Stress Disorders, Post-Traumatic/epidemiology , Adult , Aged , Chronic Pain/physiopathology , Comorbidity , Female , Fibromyalgia/physiopathology , Humans , Middle Aged , Prevalence , Self Report , Stress Disorders, Post-Traumatic/physiopathology , Surveys and Questionnaires
12.
Psychol Med ; 47(7): 1259-1270, 2017 May.
Article in English | MEDLINE | ID: mdl-28065167

ABSTRACT

BACKGROUND: A previous small study suggested that Brain Network Activation (BNA), a novel ERP-based brain network analysis, may have diagnostic utility in attention deficit hyperactivity disorder (ADHD). In this study we examined the diagnostic capability of a new advanced version of the BNA methodology on a larger population of adults with and without ADHD. METHOD: Subjects were unmedicated right-handed 18- to 55-year-old adults of both sexes with and without a DSM-IV diagnosis of ADHD. We collected EEG while the subjects were performing a response inhibition task (Go/NoGo) and then applied a spatio-temporal Brain Network Activation (BNA) analysis of the EEG data. This analysis produced a display of qualitative measures of brain states (BNA scores) providing information on cortical connectivity. This complex set of scores was then fed into a machine learning algorithm. RESULTS: The BNA analysis of the EEG data recorded during the Go/NoGo task demonstrated a high discriminative capacity between ADHD patients and controls (AUC = 0.92, specificity = 0.95, sensitivity = 0.86 for the Go condition; AUC = 0.84, specificity = 0.91, sensitivity = 0.76 for the NoGo condition). CONCLUSIONS: BNA methodology can help differentiate between ADHD and healthy controls based on functional brain connectivity. The data support the utility of the tool to augment clinical examinations by objective evaluation of electrophysiological changes associated with ADHD. Results also support a network-based approach to the study of ADHD.


Subject(s)
Attention Deficit Disorder with Hyperactivity/physiopathology , Electroencephalography/methods , Evoked Potentials/physiology , Executive Function/physiology , Inhibition, Psychological , Nerve Net/physiopathology , Adolescent , Adult , Electroencephalography/standards , Female , Humans , Male , Middle Aged , Sensitivity and Specificity , Young Adult
13.
Brain Inj ; 31(2): 237-246, 2017.
Article in English | MEDLINE | ID: mdl-28055228

ABSTRACT

BACKGROUND: The clinical diagnosis and management of patients with sport-related concussion is largely dependent on subjectively reported symptoms, clinical examinations, cognitive, balance, vestibular and oculomotor testing. Consequently, there is an unmet need for objective assessment tools that can identify the injury from a physiological perspective and add an important layer of information to the clinician's decision-making process. OBJECTIVE: The goal of the study was to evaluate the clinical utility of the EEG-based tool named Brain Network Activation (BNA) as a longitudinal assessment method of brain function in the management of young athletes with concussion. METHODS: Athletes with concussion (n = 86) and age-matched controls (n = 81) were evaluated at four time points with symptom questionnaires and BNA. BNA scores were calculated by comparing functional networks to a previously defined normative reference brain network model to the same cognitive task. RESULTS: Subjects above 16 years of age exhibited a significant decrease in BNA scores immediately following injury, as well as notable changes in functional network activity, relative to the controls. Three representative case studies of the tested population are discussed in detail, to demonstrate the clinical utility of BNA. CONCLUSION: The data support the utility of BNA to augment clinical examinations, symptoms and additional tests by providing an effective method for evaluating objective electrophysiological changes associated with sport-related concussions.


Subject(s)
Athletic Injuries/diagnosis , Brain Concussion/diagnosis , Brain/physiopathology , Nerve Net/physiopathology , Adolescent , Athletes , Athletic Injuries/physiopathology , Brain Concussion/physiopathology , Cognition/physiology , Electroencephalography , Female , Humans , Male , Neuropsychological Tests , Reaction Time/physiology , Young Adult
14.
Ann Cardiol Angeiol (Paris) ; 66(1): 32-41, 2017 Feb.
Article in French | MEDLINE | ID: mdl-27211352

ABSTRACT

In recent years, a large body of evidence has revealed the limitations of angiographic evaluation in determining the physiological significance of coronary stenosis, particularly when these are intermediate lesions. Percutaneous coronary interventions (PCI) guided by physiological assessment using fractional flow reserve (FFR) have been shown to reduce cardiovascular events when compared to angiography alone. Recently, another coronary physiologic parameter has been introduced: the "instantaneous wave-free ratio" (iFR). In this review, we will discuss the FFR, the iFR, and their use in the functional assessment of coronary stenosis in the cardiac catheterization laboratory. This review will cover theoretical aspects for non-interventional cardiologists, as well as practice points and common pitfalls related to coronary physiological assessment for interventional cardiologists.


Subject(s)
Cardiac Catheterization , Coronary Stenosis/physiopathology , Fractional Flow Reserve, Myocardial/physiology , Coronary Angiography , Coronary Circulation/physiology , Coronary Stenosis/therapy , Homeostasis/physiology , Humans , Myocardial Revascularization
15.
Transl Psychiatry ; 6(7): e853, 2016 07 12.
Article in English | MEDLINE | ID: mdl-27404285

ABSTRACT

Although of great public health relevance, the mechanisms underlying disordered eating behavior and body weight regulation remain insufficiently understood. Compelling preclinical evidence corroborates a critical role of the endocannabinoid system (ECS) in the central regulation of appetite and food intake. However, in vivo human evidence on ECS functioning in brain circuits involved in food intake regulation as well as its relationship with body weight is lacking, both in health and disease. Here, we measured cannabinoid 1 receptor (CB1R) availability using positron emission tomography (PET) with [(18)F]MK-9470 in 54 patients with food intake disorders (FID) covering a wide body mass index (BMI) range (anorexia nervosa, bulimia nervosa, functional dyspepsia with weight loss and obesity; BMI range=12.5-40.6 kg/m(2)) and 26 age-, gender- and average BMI-matched healthy subjects (BMI range=18.5-26.6 kg/m(2)). The association between regional CB1R availability and BMI was assessed within predefined homeostatic and reward-related regions of interest using voxel-based linear regression analyses. CB1R availability was inversely associated with BMI in homeostatic brain regions such as the hypothalamus and brainstem areas in both patients with FID and healthy subjects. However, in FID patients, CB1R availability was also negatively correlated with BMI throughout the mesolimbic reward system (midbrain, striatum, insula, amygdala and orbitofrontal cortex), which constitutes the key circuit implicated in processing appetitive motivation and hedonic value of perceived food rewards. Our results indicate that the cerebral homeostatic CB1R system is inextricably linked to BMI, with additional involvement of reward areas under conditions of disordered body weight.


Subject(s)
Anorexia Nervosa/diagnostic imaging , Brain/diagnostic imaging , Bulimia Nervosa/diagnostic imaging , Dyspepsia/diagnostic imaging , Obesity/diagnostic imaging , Receptor, Cannabinoid, CB1/metabolism , Adolescent , Adult , Aged , Amygdala/diagnostic imaging , Amygdala/metabolism , Anorexia Nervosa/metabolism , Body Mass Index , Brain/metabolism , Bulimia Nervosa/metabolism , Case-Control Studies , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Cerebrum/diagnostic imaging , Cerebrum/metabolism , Dyspepsia/metabolism , Female , Frontal Lobe/diagnostic imaging , Frontal Lobe/metabolism , Humans , Linear Models , Male , Mesencephalon/diagnostic imaging , Mesencephalon/metabolism , Middle Aged , Neostriatum/diagnostic imaging , Neostriatum/metabolism , Obesity/metabolism , Positron-Emission Tomography , Prefrontal Cortex/diagnostic imaging , Prefrontal Cortex/metabolism , Pyridines , Radiopharmaceuticals , Weight Loss , Young Adult
16.
Neurogastroenterol Motil ; 28(9): 1419-32, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27132547

ABSTRACT

BACKGROUND: Patients with Crohn's disease (CD) in remission are exposed to chronic psychological distress, due to the constant risk of relapse. This permanent situation of anticipation and uncertainty can lead to anxiety, which may, in turn, trigger relapse. We aimed to investigate the effects of uncertainty on behavioral and brain responses to anticipation of visceral discomfort in quiescent CD patients. METHODS: Barostat-controlled rectal distensions were preceded by cued uncertain or certain anticipation in nine CD patients and nine matched healthy volunteers. Brain responses obtained before distension across the different anticipation conditions in regions of interest (ROI) involved in (anticipation of) pain were measured using functional magnetic resonance imaging and compared between CD and controls. The association between anxiety-related psychological variables and cerebral anticipatory activity was tested. KEY RESULTS: During uncertainty, CD patients had significantly stronger activations than controls in the cingulate cortex, insula, amygdala, and thalamus with trends in the hippocampus, prefrontal, and secondary somatosensory cortex. In patients, brain responses to uncertainty in the majority of ROI correlated positively with gastrointestinal symptom-specific anxiety, trait-anxiety, and intolerance of uncertainty. CONCLUSIONS & INFERENCES: In a context of uncertainty regarding occurrence of uncomfortable visceral sensations, CD is associated with excessive reactivity in brain regions known to be involved in sensory, cognitive and emotional aspects of pain processing and modulation, and threat appraisal. Our findings contribute to a better understanding of the role of emotional and cognitive processes in CD. This may, in turn, lead to the development of new (psycho)therapeutic approaches for management of symptoms and related anxiety.


Subject(s)
Anticipation, Psychological/physiology , Anxiety/diagnostic imaging , Brain/diagnostic imaging , Crohn Disease/diagnostic imaging , Stress, Psychological/diagnostic imaging , Adult , Anxiety/complications , Anxiety/physiopathology , Brain/physiopathology , Crohn Disease/complications , Crohn Disease/physiopathology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Stress, Psychological/complications , Stress, Psychological/physiopathology , Uncertainty , Young Adult
17.
Ann Cardiol Angeiol (Paris) ; 65(2): 87-94, 2016 Apr.
Article in French | MEDLINE | ID: mdl-26926776

ABSTRACT

Contrast-induced nephropathy (CIN) is common in hospitalized patients. Its occurrence is associated with an increased hospitalization stay and cost, morbidity and mortality. Thus, preventives strategies remain a major issue. Patients that are referred for cardiac catheterization are among the most vulnerable to develop CIN due to their comorbidities. Moreover, in some cases, such preventives measures cannot be introduced due to emergent clinical settings. After a summary regarding the properties of iodinated contrast medium, the aim of this work was to review the definition, pathophysiology, diagnosis and preventive strategies related to CIN.


Subject(s)
Acute Kidney Injury/chemically induced , Acute Kidney Injury/diagnosis , Contrast Media/adverse effects , Coronary Angiography , Length of Stay , Acute Kidney Injury/epidemiology , Acute Kidney Injury/prevention & control , Biomarkers/blood , Canada/epidemiology , Contrast Media/administration & dosage , Coronary Angiography/adverse effects , Creatinine/blood , Glomerular Filtration Rate , Humans , Risk Factors
18.
Chemosphere ; 147: 420-9, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26774308

ABSTRACT

In the natural environment, heavy metal contamination can occur as long-term pollution of sites or as pulses of pollutants from wastewater disposal. In this study two freshwater green algae, Chlorella sp. FleB1 and Scenedesmus YaA6, were isolated from lead-polluted water samples and the effects of 24 h vs 4 and 8 d exposure of cultures to lead on growth, photosynthetic physiology and production of reactive oxygen species (ROS) of these algae were investigated. In Chlorella sp. FleB1, there was agreement between lead impacts on chlorophyll content, photosynthesis and growth in most case. However, in Scenedesmus acutus YaA6 growth was inhibited at lower lead concentrations (0.03-0.87 × 10(-9) M), under which ROS, measured by 2',7' dichlorodihydrofluorescein diacetate fluorescence, were 4.5 fold higher than in controls but photosynthesis was not affected, implying that ROS had played a role in the growth inhibition that did not involve direct effects on photosynthesis. Effects of short-term (5 h, 24 h) vs long-term (4 d and 8 d) exposure to lead were also compared between the two algae. The results contribute to our understanding of the mechanisms of lead toxicity to algae.


Subject(s)
Chlorella/drug effects , Lead/toxicity , Scenedesmus/drug effects , Water Pollutants, Chemical/toxicity , Chlorella/growth & development , Chlorella/metabolism , Chlorophyll/metabolism , Fresh Water , Photosynthesis/drug effects , Reactive Oxygen Species/metabolism , Scenedesmus/genetics , Scenedesmus/metabolism
19.
J Phys Chem B ; 119(25): 7968-74, 2015 Jun 25.
Article in English | MEDLINE | ID: mdl-26039558

ABSTRACT

Metal-respiring bacteria are microorganisms capable of oxidizing organic pollutants present in wastewater and transferring the liberated electrons to an electrode. This ability has led to their application as catalysts in bioelectrochemical systems (BESs), a sustainable technology coupling bioremediation to electricity production. Crucial for the functioning of these BESs is a complex protein architecture consisting of several surface-exposed multiheme proteins, called outer membrane cytochromes, wiring the cell metabolism to the electrode. Although the role of these proteins has been increasingly understood, little is known about the protein-electrode interactions and their impact on the performance of BESs. In this study, we used surface-enhanced resonance Raman spectroscopy in combination with electrochemical techniques to unravel the nature of the protein-electrode interaction for the outer membrane cytochrome OmcB from Desulfuromonas acetoxidans (Dace). Comparing the spectroelectrochemical properties of OmcB bound directly to the electrode surface with those of the same protein embedded inside an electroactive biofilm, we have shown that the surface-exposed cytochromes of Dace biofilms are in direct contact with the electrode surface. Even if direct binding causes protein denaturation, the biofilm possesses the ability to minimize the extent of the damage maximizing the amount of cells in direct electrical communication with the electrode.


Subject(s)
Bacterial Outer Membrane Proteins/metabolism , Bioelectric Energy Sources , Biofilms , Cytochromes/metabolism , Desulfuromonas/physiology , Electrodes , Spectrum Analysis, Raman
20.
Chem Sci ; 6(12): 6999-7007, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-29861938

ABSTRACT

Iron hangman complexes exhibit improved catalytic properties regarding O2 and H2O2 reduction, which are attributed to the presence of a proton donating group in defined vicinity of the catalytic metal centre. Surface enhanced resonance Raman (SERR) and IR (SEIRA) spectro-electrochemistry has been applied concomitantly for the first time to analyse such iron hangman porphyrin complexes attached to electrodes in aqueous solution. While the SERR spectra yield information about the redox state of the central iron, the SEIRA spectra show protonation and deprotonation events of the 2nd coordination sphere. To investigate the influence of a proton active hanging group on the heterogeneous electron transfer between the iron porphyrin and the electrode, two hangman complexes with either an acid or ester functional group were compared. Using time resolved SERR spectroscopy the electron transfer rates of both complexes were determined. Complexes with an acid group showed a slow electron transfer rate at neutral pH that increased significantly at pH 4, while complexes with an ester group exhibited a much faster, but pH independent rate. SEIRA measurements were able to determine directly for the first time a pKa value of 3.4 of a carboxylic hanging group in the immobilized state that shifted to 5.2 in D2O buffer solution. The kinetic data showed an increase of the heterogeneous electron transfer rate with the protonation degree of the acid groups. From these results, we propose a PCET which is strongly modulated by the protonation state of the acid hanging group via hydrogen bond interactions.

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