New Insights for the Renewed Phytoplankton-Bacteria Coupling Concept: the Role of the Trophic Web.

It is widely accepted that in many aquatic ecosystems bacterioplankton is dependent on and regulated by organic carbon supplied by phytoplankton, leading to coupled algae-bacteria relationship. In this study, an in-depth analysis of this relationship has been carried out by combining two approaches: (i) a correlation analyses between heterotrophic bacterial production (BP) vs. primary production (PP) or algal excretion of organic carbon (EOC), (ii) the balance between bacterial carbon demands (BCD) and the supply of C as EOC, measured as BCD:EOC ratio. During the study period (2013-2016), the algae-bacteria relationship was constantly changing from a coupling in 2013, uncoupling in 2014 and 2015, and an incipient return to coupling (in 2016). Our results show that top-down control (bacterivory) by algal mixotrophy acts as a decoupling force since it provides a fresh C source different to algal EOC to satisfy bacterial carbon demands. Notably, a relationship between the BCD:EOC ratio and the ecosystem metabolic balance (Primary production (PP): respiration (R)) was found, suggesting that PP:R may be a good predictor of the algae-bacteria coupling. This analysis, including the comparison between basal and potential ecosystem metabolic balance, can be a tool to improve knowledge on the interaction between both biotics compartments, which the traditional analyses on coupling may not capture.

Results of an early intervention programme for patients with bacteraemia: analysis of prognostic factors and mortality.

BACKGROUND: Bacteraemia is a common cause of morbidity and mortality in patients admitted to hospital. The aim of this study is to analyse the results of a two-year programme for the early optimisation of antibiotic treatment in patients admitted to the Costa del Sol Hospital (Marbella. Spain). METHODS: A prospective two-year cohort study was conducted, evaluating all episodes of bacteraemia at the Costa del Sol Hospital. Epidemiological and microbiological characteristics, any modification of the initial antibiotic treatment, prognostic risk stratification, early mortality related to the episode of bacteraemia, and mortality after the seventh day, were included in the analysis. RESULTS: Seven hundred seventy-three episodes of bacteraemia were treated, 61.6% males and 38.4% females. The mean age was 65.2 years. The condition was most commonly acquired in the community (41.4%). The bacteraemia was most frequently urological in nature (30.5%), and E coli was the microorganism most frequently isolated (31.6%). In 51.1% of the episodes, a modification was made to optimise the treatment. In the first week, 8.2% died from bacteraemia, and 4.5% had died when they were located. The highest rates of death were associated with older patients, nosocomial acquisition, no source, McCabe score rapidly fatal, Charlson index ≥3, Pitt index ≥3 and treatment remained unmodified. CONCLUSION: The existence of bacteraemia control programmes and teams composed of clinicians who are experienced in the treatment of infectious diseases, can improve the disease outcome by enabling more severe episodes of bacteraemia to be recognised and their empirical treatment optimised.

Efficacy and safety of switching to abacavir/lamivudine (ABC/3TC) plus rilpivirine (RPV) in virologically suppressed HIV-infected patients on HAART.

We analysed the efficacy and safety of switching from a regimen based on nonnucleoside reverse transcriptase inhibitors (NNRTI) or integrase inhibitors (INI) to ABC/3TC + RPV in virologically suppressed HIV-infected patients. This multicentre, retrospective study comprised asymptomatic HIV-infected patients who switched from 2 NRTI + NNRTI or 2 NRTI + INI to ABC/3TC + RPV between February 2013 and December 2013; all had undetectable HIV viral load prior to switching. Efficacy and safety, and changes in lipids and cardiovascular risk (CVR) were analysed at 48 weeks. Of 85 patients (74.1 % men, mean age 49.5 years), 83 (97.6 %) switched from a regimen based on NNRTI (EFV 74, RPV 5, ETV 2, NVP 2), and 45 (53 %) switched from TDF/FTC to ABC/3TC. The main reasons for switching were toxicity (58.8 %) and convenience (29.4 %). At 48 weeks, 78 (91.8 %) patients continued taking the same regimen; efficacy was 88 % by intention to treat, and 96 % by per protocol. Two patients were lost to follow-up and five ceased the new regimen (4 due to adverse effects and 1 virologic failure). Mean CD4 cell counts increased (744 vs. 885 cells/µL; p = 0.0001), and there were mean decreases in fasting total cholesterol (-15.9 mg/dL; p < 0.0001) and LDL-cholesterol (-11.0 mg/dL; p < 0.004), with no changes in HDL-cholesterol, triglycerides, total cholesterol:HDL-cholesterol ratio, and CVR. ABC/3TC + RPV is effective and safe in virologically-suppressed patients on antiretroviral therapy (ART). Forty-eight weeks after switching the lipid profile improved with decreases in total and LDL cholesterol.

The impact of an antimicrobial stewardship programme on the use of antimicrobials and the evolution of drug resistance.

Misuse of antibiotics can provoke increased bacterial resistance. There are no immediate prospects of any new broad-spectrum antibiotics, especially any with activity against enterobacteria, coming onto the market. Therefore, programmes should be implemented to optimise antimicrobial therapy. In a quasi-experimental study, the results for the pre-intervention year were compared with those for the 3 years following the application of an antimicrobial stewardship programme. We describe 862 interventions carried out as part of the stewardship programme at the Hospital Costa del Sol from 2009 to 2011. We examined the compliance of the empirical antimicrobial treatment with the programme recommendations and the treatment optimisation achieved by reducing the antibiotic spectrum and adjusting the dose, dosing interval and duration of treatment. In addition, we analysed the evolution of the sensitivity profile of the principal microorganisms and the financial savings achieved. 93 % of the treatment recommendations were accepted. The treatment actions taken were to corroborate the empirical treatment (46 % in 2009 and 31 % in 2011) and to reduce the antimicrobial spectrum taking into account the antibiogram results (37 % in 2009 and 58 % in 2011). The main drugs assessed were imipenem/meropenem, used in 38.6 % of the cases, and cefepime (20.1 %). The sensitivity profile of imipenem against Pseudomonas aeruginosa increased by 10 % in 2011. Savings in annual drug spending (direct costs) of 30,000 Euros were obtained. Stewardship programmes are useful tools for optimising antimicrobial therapy. They may contribute to preventing increased bacterial resistance and to reducing the long-term financial cost of antibiotic treatment.

Left ventricular mass in HIV-infected patients.

BACKGROUND: The HIV infection has been associated with an increased incidence of vascular events. Left ventricular mass (LVM) is independently associated with greater overall mortality. Various studies have shown that patients with HIV infection have higher LVM than the uninfected population. We aim to describe the distribution of LVM in an extensive series of patients with HIV infection, and the factors associated with its increase. PATIENTS AND METHODS: A cross-sectional study was performed in HIV-infected patients followed in our center from 1 December 2009 to 28 February 2011. A transthoracic echocardiography (TTE) was performed in all patients who gave their consent. Demographic variables, viroimmunological status, cardiovascular risk factors, vascular risk at 10 years (VR10) and history of exposure to antiretroviral drugs were collected. LVM was considered to be the quantitative dependent variable. A univariate analysis was performed, including in the multivariate analysis those variables with P<,05. RESULTS: A TTE was performed in 400 patients, and the LVM was calculated in 388. Mean age was 45 years, 75.5 males. Mean LVM was 39.54g/m(2.7)(95% CI: 38.35-40.73). Age, height, body mass index, VR10, hypertension, dyslipidemia, different medications within the cardiovascular area and having taken nevirapine have been used in the history of the patient were associated to greater LVM. In the multivariate analysis, use of nevirapine in the history of the patient and VR10 remained in the model. CONCLUSIONS: VR10 may be associated with greater LVM. The relationship with nevirapine may respond to an indication bias.

Left ventricular mass in HIV-infected patients. / Masa ventricular izquierda en pacientes con infección VIH.

BACKGROUND: The HIV infection has been associated with an increased incidence of vascular events. Left ventricular mass (LVM) is independently associated with greater overall mortality. Various studies have shown that patients with HIV infection have higher LVM than the uninfected population. We aim to describe the distribution of LVM in an extensive series of patients with HIV infection, and the factors associated with its increase. PATIENTS AND METHODS: A cross-sectional study was performed in HIV-infected patients followed in our center from 1 December 2009 to 28 February 2011. A transthoracic echocardiography (TTE) was performed in all patients who gave their consent. Demographic variables, viroimmunological status, cardiovascular risk factors, vascular risk at 10 years (VR10) and history of exposure to antiretroviral drugs were collected. LVM was considered to be the quantitative dependent variable. A univariate analysis was performed, including in the multivariate analysis those variables with P<,05. RESULTS: A TTE was performed in 400 patients, and the LVM was calculated in 388. Mean age was 45 years, 75.5 males. Mean LVM was 39.54g/m(2.7)(95% CI: 38.35-40.73). Age, height, body mass index, VR10, hypertension, dyslipidemia, different medications within the cardiovascular area and having taken nevirapine have been used in the history of the patient were associated to greater LVM. In the multivariate analysis, use of nevirapine in the history of the patient and VR10 remained in the model. CONCLUSIONS: VR10 may be associated with greater LVM. The relationship with nevirapine may respond to an indication bias.

Single-chamber ICD, single-zone therapy in primary and secondary prevention patients: the simpler the better?

BACKGROUND: It is now well established that implantable cardioverter defibrillator (ICD) implantation reduces mortality in patients at increased risk of sudden cardiac death. However, the best programming parameters remain controversial. Our traditional policy has followed a simple approach in the vast majority of patients. In accordance with ICD programming in the major randomized clinical trials, we programmed a single high-rate, shock-only therapy zone. We aimed to demonstrate in this observational study that simple programming is not associated with higher shock rates or mortality when compared to other published studies. METHODS: Consecutive patients who underwent single-chamber ICD implantation with single-zone, high-rate programming at our institution between 1993 and 2008 were retrospectively studied. Data were collected prospectively in a database regarding details of ICD implantation, demographic data, and indication. RESULTS: Three hundred thirty-two patients were included in our study, 31 % primary prevention and 68 % secondary prevention. Mean ejection fraction (EF) is 33.7 ± 15.3. Over a mean follow-up period of 62.5 ± 38.1 months, 135 patients experienced ICD shock (annualized event rate 7.7 %); 89 patients (26.8 %) appropriate shock in VT-ventricular fibrillation (VF), 68 patients (20.5 %) inappropriate shocks, and 22 patients (6.6 %) both. Twenty-nine patients (8.7 %) were reprogrammed to additional VT-ATP zones. Twenty-two (6.6 %) patients underwent heart transplantation. Sixty-two patients (18.6 %) died during follow-up, 43.6 % out of them due to cardiac cause, mainly progressive heart failure. CONCLUSION: Our results show that simpler settings with single-zone, high-rate programming is associated with ICD shock rates and long-term mortality that does not appear to be worse when compared with contemporary studies which include multizone ICD programming with antitachycardia pacing activated.

Short communication: contribution of the immunovirological state and traditional cardiovascular risk factors to low HDL-cholesterol in HIV patients.

The prevalence of low HDL-C levels in an HIV population and its related factors was investigated. We undertook a multicenter, cross-sectional study of all HIV patients on regular follow-up in five hospitals (Southern Spain). A physical examination and fasting laboratory analysis were performed and a questionnaire about cardiovascular risk factors was provided. One thousand and seventy-two patients were included, 43.8% of whom had low HDL-C levels. The prevalence of low HDL-C was higher among patients diagnosed with AIDS, those not on antiretroviral therapy, those with a detectable HIV viral load, those with CD4 cell counts ≤350 cells/µl, smokers, and those with hypertriglyceridemia. For patients on antiretroviral therapy, the prevalence of low HDL-C was higher for those on protease inhibitors than those taking nonnucleoside reverse transcriptase inhibitors. In the multivariate analysis, low HDL-C levels were associated with tobacco use (OR 1.37, 95% CI 1.04-1.8; p = 0.04), hypertriglyceridemia (OR 2.94, 95% CI 2.2-3.8; p < 0.00001), CD4 cells count ≤350 cells/µl (OR 1.74, 95% CI 1.2-2.3; p < 0.0001), and a detectable HIV viral load (OR 1.85, 95% CI 1.3-2.5; p < 0.0001). The immunological and virological conditions, in addition to traditional cardiovascular risk factors such as tobacco use and hypertriglyceridemia, affect HDL-C levels in HIV-infected patients. For patients on antiretroviral therapy, the use of protease inhibitors is associated with a higher probability of low levels of HDL-C. Although it is not clear if the higher HDL-C levels associated with antiretroviral use are surrogates for decreased cardiovascular disease risk, this may be another reason to start antiretroviral therapy earlier.

Atrial flutter after heart transplantation: mechanism and catheter ablation.

BACKGROUND: Atrial flutter is a frequent arrhythmia after heart transplantation, but little is known about its mechanism and treatment. We report the results of an electrophysiologic study in patients with atrial flutter after orthotopic heart transplantation, describing its mechanism and demonstrating the acute and long-term efficacy of catheter ablation for treating this arrhythmia. METHODS: We included 14 patients with symptomatic atrial flutter after orthotopic heart transplantation. All of them underwent an electrophysiologic study to determine the mechanism of the arrhythmia and catheter ablation when possible. RESULTS: Counterclockwise right atrial circuit around the tricuspid annulus involving the cavotricuspid isthmus was demonstrated in 13 patients (86%). Catheter ablation of the isthmus was performed with good acute results in all but 1. During a mean follow-up of 24 ± 17 months, recurrent atrial flutter was documented in 3 patients and atrial fibrillation in 2. In another patient, we demonstrated a left atrial origin. CONCLUSIONS: The most common mechanism of atrial flutter in heart transplant recipients is a counterclockwise circuit around the tricuspid annulus involving the cavotricuspid isthmus. Catheter ablation of the isthmus between tricuspid annulus and posterior atrial suture line represents an effective treatment in these patients. This condition may be avoided by changing the surgical technique to a bicaval anastomosis.

Impact of the most frequent chronic health conditions on the quality of life among people aged >15 years in Madrid.

BACKGROUND: This study sought to ascertain to what degree health-related quality of life (HRQL) in the City of Madrid was affected by each of the most frequent chronic health conditions, and the specific quality-of-life (QL) domains on which such health conditions had the greatest impact, taking co-morbidity and socio-demographic variables into account. METHODS: A descriptive, analytical, cross-sectional study was conducted covering 7341 subjects aged >or=16 years in the City of Madrid. Data were collected on self-reported diagnosed morbidity, including hypertension, hypercholesterolaemia, varicose veins, diabetes, chronic asthma/bronchitis, myocardial infarction/angina pectoris, stomach problems, allergy, arthrosis/arthritis or rheumatism, depression/anxiety, cataracts, cerebrovascular accidents (CVACs), chronic constipation, osteoporosis and Alzheimer's disease or dementia. HRQL was measured using the COOP/WONCA questionnaire. The effects of diagnosis, age, social class, gender and the co-morbidity were analysed using a multivariate analysis of covariance (ANCOVA). RESULTS: The chronic health conditions that registered the worst overall mean scores on the COOP/WONCA questionnaire were Alzheimer's disease or dementia, Parkinson's disease, fibromyalgia, CVACs and depression, with scores of over 26 points in all cases. After the introduction of socio-demographic variables in the model, the highest values of Snedecor's F-test corresponds to depression (F = 461.63), 'arthrosis/arthritis or rheumatism' (F = 175.41), Alzheimer's disease or dementia (F = 65.70), gastric disorders (F = 65.17), cancer (F = 43.08) and CVACs (F = 41.65). CONCLUSIONS: Depression and 'arthrosis/arthritis or rheumatism' are the two chronic health conditions, which have the greatest impact on HRQL in Madrid's citizens, therefore is mandatory to propose and implement public health strategies that would reduce the prevalence and morbidity of such disorders.

Ankle-branch index and HIV: the role of antiretrovirals.

OBJECTIVE: To study the relationship between antiretroviral (ARV) treatment and abnormal ankle-branch index (ABI) and to compare the risk factors for altered ABI. METHODS: Patients coming to the office from April 2007 until July 2007 were offered the chance to take part in the study. ABI was obtained by the standard technique. Those < or = 0.9 or > or = 1.3 were considered altered ABI. Clinical reports were reviewed to examine traditional vascular risk factors, coinfection with hepatitis C virus and/or hepatitis B virus, tobacco use, highly active antiretroviral therapy use and its components and length of use of each ARV drug. RESULTS: ABI was measured in 147 patients, 82.3% males. Thirty-three patients (22.45%) had an altered ABI, and it was related to CD4 cell nadir, dyslipidaemia and protease inhibitor (PI) use. When logistic regression was carried out, only dyslipidaemia (OR 2.68, CI 95%: 1.06-6.91) and PI use (OR 2.79, CI 95%: 1.15-6.54) remained in the model. CONCLUSIONS: Altered ABI is associated with PI use independently of dyslipidaemia. Probably, it marks patients with high vascular risk not identified with traditional scales.

Memory effect in triglycine sulfate induced by a transverse electric field: specific heat measurement.

The influence of a transverse electric field on the specific heat of triglycine sulfate (TGS) has been studied. The specific heat of TGS has been measured on heating the sample from the ferroelectric to the paraelectric phase after prolonged application of transverse electric field (i.e. perpendicular to the ferroelectric axis). It is shown that the specific heat of TGS can 'remember' the temperature T(s) at which the transverse field was previously applied.

Accurate quantification methods to evaluate cervical cord atrophy in multiple sclerosis patients.

OBJECT: Automatic accurate measurement techniques are needed to increase reproducibility in the quantification of cervical cord area (CCA) with magnetic resonance (MR) imaging in the assessment of central nervous system (CNS) atrophy in multiple sclerosis (MS) patients. MATERIALS AND METHODS: Two segmentation methods were implemented: (1) spatial mean brightness level estimation (SMBLE), and (2) partial-volume modeling (PVM). These were evaluated with the inclusion of spinal cord inclination and/or partial-volume-effect corrections. An averaged manually segmented set was considered as reference. Thirty MR studies were used to compare the different methods. A set of 15 MS patients and 15 control subjects within a two-year longitudinal study were used to evaluate cord atrophy with the best method. Statistical evaluation was made by using an intraclass correlation coefficient and Bland-Altman comparisons. RESULTS: Partial-volume modeling with spinal cord inclination correction and partial-volume spinal-cord contour contribution estimation was the most accurate method. The longitudinal test showed a 4% decrease in CCA in MS patients with no significant reduction in control subjects. CONCLUSION: The automatic PVM cord-segmentation approach, taking into consideration the spinal-cord inclination and partial-volume treatment, provides reproducibility and increased accuracy in the evaluation of cord atrophy, allowing the monitoring of changes in MS patients.

The influence of hepatitis C virus-human immunodeficiency virus co-infection on the appearance of liver enzyme elevation in people on high activity antiretroviral treatment.

BACKGROUND: Liver enzyme elevation (LEE) as a consequence of HAART is a problem among patients with HIV-HCV co-infection. METHODS: In this retrospective study, 145 patients with HIV who were on HAART and who developed LEE grades 3 and 4 of the World Health Organization (WHO) were followed up. Basal ALT, alcohol consumption, and HCV and HBV co-infection were recorded. Comparisons were made between patients with and without HCV co-infection. RESULTS: Three patients without co-infection presented LEE grade 3 versus 38 with co-infection (104 episodes). An increase in basal ALT (RR: 1.01) and HCV co-infection (RR: 6.6) were the variables associated with LEE grade 3. The number of days that HAART had to be withdrawn due to LEE was 58.15 and 4.85 in subjects with and without co-infection, respectively (p=0.024). CONCLUSION: Patients with HCV-HIV co-infection have more episodes of LEE and must go longer without HAART than people without co-infection.

Paradoxical responses in a cohort of HIV-1-infected patients with mycobacterial disease.

SETTING: Paradoxical worsening or relapse of opportunistic infections has been described after initiation of highly active anti-retroviral therapy (HAART) in human immunodeficiency virus (HIV) infected patients. DESIGN: Retrospective study of a group of 33 HIV-infected patients with mycobacterial disease analysing the incidence and characteristics of patients with and without paradoxical response after starting HAART and/or mycobacterial treatment. RESULTS: Nine patients in the group had paradoxical response. No significant difference of baseline characteristics was observed in these patients. The decrease in viral load was significantly greater among patients with paradoxical response than in patients without. CONCLUSION: No clinical difference was found in the evolution of HIV-infected patients with mycobacterial disease after the resolution of the episode of paradoxical response.

Mycobacterium fortuitum complex endocarditis-case report and literature review.

Endocarditis due to Mycobacterium fortuitum complex is a rare entity generally linked to the hospital environment. Only 18 cases have been published since 1966. Here we present a case of a female who developed an endocarditis due to Mycobacterium chelonae after valve replacement as well as a review of the literature. The course of this kind of endocarditis is generally subacute and the outcome is usually fatal. Blood cultures were positive in 75% of cases of metallic valve endocarditis, versus 20% in bioprostheses. The treatment must include antibiotics that have shown activity against these mycobacteria, such as amikacin, imipenem, cefoxitin, fluorinated quinolones and macrolides (especially clarithromycin). Surgical removal is recommended. Although the prognosis for the patient is poor, we should expect better outcomes with the use of new antibiotic regimens.

[Behcet's disease therapy review]. / Tratamiento de la enfermedad de Behçet.

Behçet's disease is an inflammatory process of unknown origin, which usually presents with recurrent oral ulcers, genital aphthae, uveitis and cutaneous lesions. However, a wide variety of clinical manifestations have been reported, and virtually any organ system may be affected, showing central nervous system, joints, blood vessels or gastrointestinal tract involvement. Therapeutic approach remains complex, and varies in basis of the affected organs. Complex aphthosis may respond to topical therapy, colchicine and dapsone. If this therapy does not result in adequate disease control, thalidomide, oral prednisone and methotrexate may be useful. When severe ocular lesions or systemic manifestations are present, therapies tend to be more aggressive, usually combining corticosteroids with immunosuppressive agents as cyclosporin, azathioprine, cyclophosphamide, interferon-alfa-2a, and chlorambucil.

[Guidelines of the Spanish Society of Cardiology on requirements and equipment in electrophysiology]. / Guías de práctica clínica de la Sociedad Española de Cardiología sobre requerimientos y equipamiento en electrofisiología.

Due to the enormous qualitative and quantitative evolution that clinical electrophysiology has experienced over the past years, specific Units dedicated to the management of patients with cardiac arrhythmias have been created. In these guidelines, the minimum technical and human needs of an Arrhythmia Unit are discussed.