141 research outputs found
OTELO survey: Deep BVRI broad-band photometry of the Groth strip
Context. The Groth field is one of the sky regions that will be targeted by the OTELO (OSIRIS Tunable Filter Emission Line Object) survey in the optical 820 nm and 920 nm atmospheric windows. A complementary broad-band photometric catalogue of the field is essential for several purposes, in particular the inequivocal identification of sources, photometric redshift estimation, and population synthesis fitting.Aims. We aim to describe the OTELO survey and present deep BVRI imaging data of the Groth field. Galaxy number counts, colour distributions and galaxy clustering are analysed.Methods. BVRI deep images (?8 ks) were obtained with the Prime Focus Camera at the WHT (La Palma) and reduced with the IRAF package. The extraction and photometry of the sources was done with SExtractor software. We analysed the final catalogue to obtain galaxy number counts, as well as galaxy correlation functions as a function of I magnitude and V - I colour. It is also compared with estimations from mock catalogues of the Virgo-Millenium consortium.Results. We find excellent agreement between observed and mock data number counts. We also find evidence of galaxy clustering evolution and strong dependence of the angular correlation function on the V - I observed colour. Our data favour a flattening of the clustering amplitude with median apparent magnitude. The good general agreement between our clustering analysis and the estimates from the mock data is remarkableAcknowledgements. This work was supported by the Spanish Plan Nacional de Astronomía y Astrofísica under grants AYA2005–04149 and AYA2006–2358. We thank the referee for helpful comments that improved the clarity of this paper. The Millennium Simulation databases used in this paper and the web application providing online access to them were constructed as part of the activities of the German Astrophysical Virtual Observatory. IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation
Cardiac resynchronization therapy and valvular cardiomyopathy after corrective surgery
Cardiac resynchronization therapy (CRT) has been
shown to have clinical benefits in certain groups of
patients with advanced heart failure (HF). However,
patients with valvular cardiomyopathy are
underrepresented in randomized clinical studies. The aim
of this study was to assess the medium-term (i.e., at 6
months) effects of CRT in patients with HF exclusively
due to valvular disease. The study included 40
consecutive patients who underwent CRT device
implantation. At 6 months, there were improvements in
functional class, left ventricular remodeling, and
intraventricular dyssynchrony parameters in treated
patients. In this particular subgroup of patients, the
benefits of CRT were similar to those observed in patients
with HF due to other etiologies
Development of a 3D Ni-Mn binary oxide anode for energy-efficient electro-oxidation of organic pollutants
The depletion of clean water resources and the consequent accumulation of contaminants in aquatic systemsmust be urgently addressed by means of innovative solutions. Electro-oxidation (EO) is considered a promisingtechnology, prized for its versatility and eco-friendliness. However, the excessively high prices and the toxicityassociated with some of the materials currently employed for EO impede its broader application. This studyintroduces cost-effective Ni-Mn binary oxide anodes prepared on Ni foam (NF) substrate. A scalable synthesisroute that enables a 35-fold increase in the production of active material through a single optimization step hasbeen devised. The synthesized binary oxide material underwent electrochemical characterization, and itseffectiveness was assessed in an electrochemical flow-through cell, benchmarked against single Ni or Mn oxidesand more conventional alternatives like boron-doped diamond (BDD) and dimensionally-stable anode (DSA). Thenovel binary oxide anode demonstrated exceptional performance, achieving complete removal of phenol at verylow current density of 5 mA cm-2, along with an 80% of chemical oxygen demand (COD) decay within only60 min. The NF/NiMnO3 anode outperformed the BDD and DSA when using comparable projected surface areas,owing to its high porosity and ability to produce hydroxyl radicals, as confirmed from the degradation profiles inthe presence of radical scavengers. Furthermore, GC/MS analysis served to elucidate the degradation pathwaysof phenol
Efecto de la localización del electrodo ventricular izquierdo sobre los parámetros ecocardiográficos de asincronía en pacientes sometidos a terapia de resincronización cardíaca
Introduction and objectives. Cardiac resynchronization
therapy has been shown to be an option in the treatment
of patients with congestive heart failure. The current
indication for this treatment is based on clinical and electrocardiographic
criteria, although echocardiography has
also been shown to be a useful tool for the diagnosis of
ventricular dyssynchrony. The aim of this study was to assess
left ventricular dyssynchrony by echocardiography
and to evaluate the effect of the stimulation site on the
magnitude of resynchronization.
Patients and method. We studied 25 patients with biventricular
stimulation (left ventricular lead located in a lateral
position in 13 patients, and in an anterior position in
12). A complete echo-Doppler evaluation, including left
ventricular ejection fraction, ventricular diameters and parameters
of inter- and intraventricular dyssynchrony, was
performed before implantation and 3 months after the
procedure, with the device connected and disconnected.
Results. Left ventricular ejection fraction increased significantly
from 23.7 (6.5) to 27.8 (5.5) (P=.007) at 3
months. In the group as a whole, biventricular pacing was
associated with a significant decrease in all intraventricular
dyssynchrony parameters (septal-to-lateral wall motion
delay and septal-to-posterior wall motion delay). This decrease
in septal-to-posterior wall motion delay and septalto-
lateral wall motion delay was significantly greater in patients
with the electrode implanted in the lateral position
(58.1 ms vs 118 ms; P=.02) than with the lead in the anterior
position (39.5 ms vs 86.5 ms; P=.04). Three patients,
all with the electrode in an anterior location, were considered
non-responders.
Conclusions. Left lateral free wall stimulation provided
significantly better intraventricular resynchronization compared
to stimulation at an anterior site. Echocardiography
is a useful tool to evaluate changes in intra- and interventricular
synchrony related to the pacing site
Liver transplantation in cirrhotic patients with diabetes mellitus: Midterm results, survival, and adverse events
Liver cirrhosis is frequently associated with diabetes mellitus (DM), and this
metabolic complication is also frequent after orthotopic liver transplantation
(OLT). The aim of our study is to investigate which factors are associated with
DM before and after OLT and their impact on post-OLT evolution. We evaluated the
prevalence of DM among 115 liver transplant candidates with cirrhosis and
assessed their evolution after OLT (median follow-up, 41 months). Sixteen
candidates had DM requiring pharmacological therapy (group A), 45 candidates had
DM controlled with diet (group B), and 54 candidates did not have DM (group C).
One-year and 3-year actuarial survival rates were 100% and 100% for group A, 91%
and 85% for group B, and 77% and 74% for group C, respectively (P <.03). Post-OLT
DM was more frequent in group A. The incidence of other metabolic complications,
major infections, rejection, and arterial hypertension; the need for
hospitalization; and renal and graft function of patients in groups A, B, and C
were similar. The only risk factor for DM 1 year after OLT on multivariate
analysis was pre-OLT DM requiring pharmacological treatment. The incidence of
complications, need for hospitalization, and renal and graft function 1 year
after OLT for patients with post-OLT DM were similar to those of patients without
post-OLT DM. In conclusion, patients with cirrhosis who have DM have a greater
risk for post-OLT DM, but their midterm survival is not worse than the survival
of those without DM
Tratamiento de la insuficiencia cardíaca avanzada mediante estimulación biventricular. Experiencia inicial en una serie de 22 casos consecutivos
Recent data suggest that biventricular pacing may play
an important role in treating advanced heart failure in the presence of a
significant interventricular and/or intraventricular conduction disorder by
correcting cardiac dysynchrony. In this article, we review the initial technical
and clinical experience with cardiac resynchronization therapy in an
electrophysiology laboratory. METHODS: The first 22 consecutive patients with
severe congestive heart failure, ejection fraction < 0.35, NYHA functional class
III or IV, and QRS duration > 120 ms who were implanted biventricular pacemakers
were studied. Clinical, electrocardiographic, and echocardiographic evaluations
were made before and three months after pacemaker implantation. Acute functional
capacity testing with peak oxygen uptake was measured during biventricular pacing
and during intrinsic rhythm or right ventricular pacing three months after the
implantation procedure. RESULTS: The success rate of pacemaker implantation was
95%. Pre-discharge left ventricular pacing was achieved in 91%, with an average
pacing threshold of 1.53 (1.04) volts. NYHA functional class improved (p = 0.039)
from 3.4 (0.7) to 2.3 (0.78). The rate of hospitalization for heart failure
decreased from an average of 3.12 (0.58) three months before the procedure to
1.38 (0.34) three months after the procedure. Peak oxygen uptake was
significantly greater (p = 0.028) during biventricular pacing: 14.89 (2.1)
ml/min/kg, than during intrinsic rhythm or right ventricular pacing: 12.65 (2.3)
ml/min/kg. CONCLUSIONS: Cardiac resynchronization therapy can be performed safely
and with a high success rate in the electrophysiology laboratory. Biventricular
pacing seems to improve the symptoms of congestive heart failure in patients with
evidence of atrioventricular and/or interventricular/intraventricular
dysynchrony. An acute benefit in peak oxygen uptake was associated with
biventricular pacing after the implantation procedure
CD4+/CD25+ regulatory cells inhibit activation of tumor-primed CD4+ T cells with IFN-gamma-dependent antiangiogenic activity, as well as long-lasting tumor immunity elicited by peptide vaccination
CD25(+) regulatory T (T reg) cells suppress the activation/proliferation of other CD4(+) or CD8(+) T cells in vitro. Also, down-regulation of CD25(+) T reg cells enhance antitumor immune responses. In this study, we show that depletion of CD25(+) T reg cells allows the host to induce both CD4(+) and CD8(+) antitumoral responses following tumor challenge. Simultaneous depletion of CD25(+) and CD8(+) cells, as well as adoptive transfer experiments, revealed that tumor-specific CD4(+) T cells, which emerged in the absence of CD25(+) T reg cells, were able to reject CT26 colon cancer cells, a MHC class II-negative tumor. The antitumoral effect mediated by CD4(+) T cells was dependent on IFN-gamma production, which exerted a potent antiangiogenic activity. The capacity of the host to mount this antitumor response is lost once the number of CD25(+) T reg cells is restored over time. However, CD25(+) T reg cell depletion before immunization with AH1 (a cytotoxic T cell determinant from CT26 tumor cells) permits the induction of a long-lasting antitumoral immune response, not observed if immunization is conducted in the presence of regulatory cells. A study of the effect of different levels of depletion of CD25(+) T reg cells before immunization with the peptide AH1 alone, or in combination with a Th determinant, unraveled that Th cells play an important role in overcoming the suppressive effect of CD25(+) T reg on the induction of long-lasting cellular immune responses
Production of interleukin-2 in response to synthetic peptides from hepatitis C virus E1 protein in patients with chronic hepatitis C: relationship with the response to interferon treatment
BACKGROUND/AIMS:
The role of cellular immunity in the clearance of hepatitis C virus after interferon therapy has not yet been elucidated. Here, we analyzed the T cell response to peptides from hepatitis C virus E1 protein in untreated and interferon-treated patients with chronic hepatitis C virus infection.
METHODS:
We used thirty-six 15-mer synthetic peptides from hepatitis C virus E1 protein (genotype 1a) in a sensitive interleukin-2 production assay in two groups of controls (healthy seronegative individuals and patients with liver diseases unrelated to hepatitis C virus), and three groups of patients with chronic hepatitis C: nine patients who cleared the virus after interferon treatment (group 1), nine patients who failed to respond to the therapy (group 2) and nine previously untreated patients (group 3).
RESULTS:
None of the controls responded to any of the peptides tested, whereas 8/9 (88%) of patients from group 1 responded positively. In contrast, only 2/9 (22%) of patients from group 2 showed peptide recognition. In group 3, 5/9 patients (55%) displayed positive response against E1 peptides. When E1 peptides from the sequence corresponding to genotype 1b (the commonest in patients who were non-responders to interferon) were tested in nine additional interferon-resistant patients (group 2*) a positive response was detected in only three of them (33%).
CONCLUSIONS:
T cell recognition of hepatitis C virus E1 peptides in patients with chronic hepatitis C who exhibit sustained response to interferon therapy is increased as compared with interferon-resistant cases, suggesting that T cell immunity to hepatitis C virus structural proteins may play a role in the clearance of this viral infection
Enhancement of CD4 and CD8 immunity by anti-CD137 (4-1BB) monoclonal antibodies during hepatitis C vaccination with recombinant adenovirus
The induction of protective or therapeutic cellular immunity against hepatitis C virus (HCV) is a difficult goal. In a previous work we showed that immunization with a recombinant adenovirus encoding HCV-NS3 (RAdNS3) could partially protect mice from challenge with a vaccinia virus encoding HCV antigens. We sought to investigate whether systemic administration of an immunostimulatory monoclonal antibody directed against the lymphocyte surface molecule CD137 could enhance the immunity elicited by RAdNS3. It was found that treatment with anti-CD137 mAb after the administration of a suboptimal dose of RAdNS3 enhanced cytotoxic and T helper cell responses against HCV NS3. Importantly, the ability of RAdNS3 to induce protective immunity against challenge with a recombinant vaccinia virus expressing HCV proteins was markedly augmented. Thus, combination of immunostimulatory anti-CD137 mAb with recombinant adenoviruses expressing HCV proteins might be useful in strategies of immunization against HCV
Immunization with a tumor-associated CTL epitope plus a tumor-related or unrelated Th1 helper peptide elicits protective CTL immunity
Immunization with cytotoxic T cell epitope SPSYVYHQF (AH1), derived from MuLV gp70 envelope protein expressed by CT26 tumor cells, does not protect BALB/c mice against challenge with CT26 tumor cells. By contrast, immunization with AH1 plus T helper peptides OVA(323-337) or SWM(106-118) eliciting Th1 and Th0 profiles, protected 83% and 33% of mice, respectively. Interestingly, immunization with AH1 plus both helper peptides reverted the efficacy to 33%. We identified the endogenous T helper peptide p(320-333) from gp70 which elicits a Th1 profile and is naturally processed. As for OVA(323-337), immunization with p(320-333) alone did not protect against tumor challenge. However, p(320-333) plus AH1 protected 89% of mice at day 10 after vaccination. Only 20% of mice vaccinated with AH1 + OVA(323-337) or AH1 + p(320-333) were protected when challenged 80 days after immunization. Treatment with OVA(323-337) or with p(320-333) around established tumors delayed tumor growth. Our results show that tumor-related as well as tumor-unrelated but strong Th1 peptides may be useful for inducing CTL responses in tumor immunotherapy
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