The influence of frequency, volume, and viscosity on the ultrasonic atomization threshold of sessile droplets.

In this research, we present a study on the atomization threshold (ATh) of sessile droplets, analyzing its relationship with the excitation frequency fexc (55-48 kHz), droplet volume Vdrop (1-100 µl), and droplet viscosity µ (1-6 mPa⋅s). The investigation focused on the atomization thresholds using ultrasonic excitation of distilled water droplets and water- polyethylene glycol (PEG)-8000 mixtures deposited on vibrating surfaces. The obtained results are compared with previously reported theoretical models. A modification to the model proposed by Alzuaga et al. [Alzuaga, Manceau, and Bastien, J. Sound Vib. 282(1-2), 151-162 (2005)] is suggested to determine the atomization thresholds of sessile droplets, incorporating the atomization droplet size equation proposed by Rajan and Pandit and an empirical constant α to account for the effect of droplet volume in this process. The results show that the relationship between the atomization threshold and viscosity does not fit well with the prediction of Eisenmenger [Acta Acust united Acust. 9(4), 327-340 (1959)] and Pohlman and Stamm [Untersuchung Zum Mechanismus Der Ultraschallvernebelung an Flüssigkeitsoberflächen im Hinblick Auf Technische Anwendungen (Investigation on the Mechanism of Ultrasonic Nebulization on Liquid Surfaces Considering Technical Applications) (VS Verlag für Sozialwissenschaften, Wiesbaden, Germany, 1965)] and Pohlman et al. [Pohlman, Heisler, and Cichos, Ultrasonicc 12(1), 11-15 (1974)] (ATh∝µ). However, the data tendency aligns with the model proposed by Alzuaga (ATh ∝ µ1/2). The results obtained in this study provide a deeper understanding of the atomization thresholds of sessile droplets through ultrasonic excitation.

Characterization of Novel Trypanosoma cruzi-Specific Antigen with Potential Use in the Diagnosis of Chagas Disease.

Chagas disease is caused by the parasite Trypanosoma cruzi. In humans, it evolves into a chronic disease, eventually resulting in cardiac, digestive, and/or neurological disorders. In the present study, we characterized a novel T. cruzi antigen named Tc323 (TcCLB.504087.20), recognized by a single-chain monoclonal antibody (scFv 6B6) isolated from the B cells of patients with cardiomyopathy related to chronic Chagas disease. Tc323, a ~323 kDa protein, is an uncharacterized protein showing putative quinoprotein alcohol dehydrogenase-like domains. A computational molecular docking study revealed that the scFv 6B6 binds to an internal domain of Tc323. Immunofluorescence microscopy and Western Blot showed that Tc323 is expressed in the main developmental forms of T. cruzi, localized intracellularly and exhibiting a membrane-associated pattern. According to phylogenetic analysis, Tc323 is highly conserved throughout evolution in all the lineages of T. cruzi so far identified, but it is absent in Leishmania spp. and Trypanosoma brucei. Most interestingly, only plasma samples from patients infected with T. cruzi and those with mixed infection with Leishmania spp. reacted against Tc323. Collectively, our findings demonstrate that Tc323 is a promising candidate for the differential serodiagnosis of chronic Chagas disease in areas where T. cruzi and Leishmania spp. infections coexist.

Changes in the Expression of TGF-Beta Regulatory Pathway Genes Induced by Vitamin D in Patients with Relapsing-Remitting Multiple Sclerosis.

Vitamin D is an environmental factor related to multiple sclerosis that plays a significant role in immune regulation. TGF-ß is a superfamily of cytokines with an important dual effect on the immune system. TGF-ß inhibits the Th1 response while facilitating the preservation of regulatory T cells (FOXP3+) in an immunoregulatory capacity. However, when IL-6 is present, it stimulates the Th17 response. Our aim was to analyze the regulatory effect of vitamin D on the in vivo TGF-ß signaling pathway in patients with relapsing-remitting multiple sclerosis (RRMS). A total of 21 patients with vitamin D levels < 30 ng/mL were recruited and supplemented with oral vitamin D. All patients were receiving disease-modifying therapy, with the majority being on natalizumab. Expression of SMAD7, ERK1, ZMIZ1, BMP2, BMPRII, BMP4, and BMP5 was measured in CD4+ lymphocytes isolated from peripheral blood at baseline and one and six months after supplementation. SMAD7 was overexpressed at six months with respect to baseline and month one. ERK1 was overexpressed at six months with respect to month one of treatment. No significant differences in expression were observed for the remaining genes. No direct correlation was found with serum vitamin D levels. BMPRII expression changed differentially in non-natalizumab- versus natalizumab-treated patients. Changes were observed in the expression of ERK1, BMP2, and BMP5 based on disease activity measured using the Rio-Score, BMP2 in patients who had relapses, and BMP5 in those whose EDSS worsened. Our results suggest indirect regulation of vitamin D in TGF-ß pathway genes in patients with RRMS.

In Silico Guided Discovery of Novel Class I and II Trypanosoma cruzi Epitopes Recognized by T Cells from Chagas' Disease Patients.

T cell-mediated immune response plays a crucial role in controlling Trypanosoma cruzi infection and parasite burden, but it is also involved in the clinical onset and progression of chronic Chagas' disease. Therefore, the study of T cells is central to the understanding of the immune response against the parasite and its implications for the infected organism. The complexity of the parasite-host interactions hampers the identification and characterization of T cell-activating epitopes. We approached this issue by combining in silico and in vitro methods to interrogate patients' T cells specificity. Fifty T. cruzi peptides predicted to bind a broad range of class I and II HLA molecules were selected for in vitro screening against PBMC samples from a cohort of chronic Chagas' disease patients, using IFN-γ secretion as a readout. Seven of these peptides were shown to activate this type of T cell response, and four out of these contain class I and II epitopes that, to our knowledge, are first described in this study. The remaining three contain sequences that had been previously demonstrated to induce CD8+ T cell response in Chagas' disease patients, or bind HLA-A*02:01, but are, in this study, demonstrated to engage CD4+ T cells. We also assessed the degree of differentiation of activated T cells and looked into the HLA variants that might restrict the recognition of these peptides in the context of human T. cruzi infection.

The cytosolic tryparedoxin peroxidase from Trypanosoma cruzi induces a pro-inflammatory Th1 immune response in a peroxidatic cysteine-dependent manner.

Trypanosoma cruzi cytosolic tryparedoxin peroxidase (c-TXNPx) is a 2-Cys peroxiredoxin (Prx) with an important role in detoxifying host cell oxidative molecules during parasite infection. c-TXNPx is a virulence factor, as its overexpression enhances parasite infectivity and resistance to exogenous oxidation. As Prxs from other organisms possess immunomodulatory properties, we studied the effects of c-TXNPx in the immune response and analysed whether the presence of the peroxidatic cysteine is necessary to mediate these properties. To this end, we used a recombinant c-TXNPx and a mutant version (c-TXNPxC52S) lacking the peroxidatic cysteine. We first analysed the oligomerization profile, oxidation state and peroxidase activity of both proteins by gel filtration, Western blot and enzymatic assay, respectively. To investigate their immunological properties, we analysed the phenotype and functional activity of macrophage and dendritic cells and the T-cell response by flow cytometry after injection into mice. Our results show that c-TXNPx, but not c-TXNPxC52S, induces the recruitment of IL-12/23p40-producing innate antigen-presenting cells and promotes a strong specific Th1 immune response. Finally, we studied the cellular and humoral immune response developed in the context of parasite natural infection and found that only wild-type c-TXNPx induces proliferation and high levels of IFN-γ secretion in PBMC from chronic patients without demonstrable cardiac manifestations. In conclusion, we demonstrate that c-TXNPx possesses pro-inflammatory properties that depend on the presence of peroxidatic cysteine that is essential for peroxidase activity and quaternary structure of the protein and could contribute to rational design of immune-based strategies against Chagas disease.

New Scheme of Intermittent Benznidazole Administration in Patients Chronically Infected with Trypanosoma cruzi: Clinical, Parasitological, and Serological Assessment after Three Years of Follow-Up.

In a pilot study, we showed that the intermittent administration of benznidazole in chronic Chagas disease patients resulted in a low rate of treatment suspension and therapeutic failure, as assessed by quantitative PCR (qPCR) at the end of treatment. Here, a 3-year posttreatment follow-up study of the same cohort of patients is presented. The treatment scheme consisted of 12 doses of benznidazole at 5 mg/kg of body weight/day in two daily doses every 5 days. Parasite load, Trypanosoma cruzi-specific antibodies, and serum chemokine levels were measured prior to treatment and after a median follow-up of 36 months posttreatment by DNA minicircle kinetoplastid and nuclear DNA satellite sequence qPCR methods, conventional serological techniques, a Luminex-based assay with recombinant T. cruzi proteins, and a cytometric bead array. At the end of follow-up, 14 of 17 (82%) patients had negative qPCR findings, whereas three of 17 (18%) had detectable nonquantifiable findings by at least one of the qPCR techniques. A decline in parasite-specific antibodies at 12 months posttreatment was confirmed by conventional serological tests and the Luminex assays. Monocyte chemoattractant protein 1 levels increased after treatment, whereas monokine induced by gamma interferon levels decreased. New posttreatment electrocardiographic abnormalities were observed in only one patient who had cardiomyopathy prior to treatment. Together, these data strengthen our previous findings by showing that the intermittent administration of benznidazole results in a low rate of treatment suspension, with treatment efficacy comparable to that of a daily dose of 5 mg/kg for 60 days.

Survival of Entomopathogenic Nematodes in Oil Emulsions and Control Effectiveness on Adult Engorged Ticks (Acari: Ixodida).

Although their control is based on chemical products, the infestations by ticks (Ixodes scapularis Say) are causing great losses and damages in the livestock production worldwide. In this study, the survival of the entomopathogenic nematodes Heterorhabditis bacteriophora, Steinernema carpocapsae and Steinernema websteri in vegetal oil suspension at concentrations of 13% and 33% and their effectiveness to control ticks at concentrations of 50 ± 5 and 100 ± 10 nematodes in oil suspensions of Cymbopogon citratus, Pelargonium sp, Juniperus virginiana, Rosa sp, and Mentha piperita were evaluated in lab conditions. In field conditions, the Lethal Concentration (LC90) of S. websteri in oil suspensions of J. virginiana and C. citratus in dogs infested with ticks was evaluated. In the laboratory, it was found that an oil emulsion of C. citratus and J. virginiana at 13% maintained the survival of S. carpocapsae, H. bacteriophora and S. websteri from 55% to 60% for a period of 96 hr. The combination of the S. websteri nematode with 50 or 100 nematodes in oil emulsions of J. virginiana at 33% presented a control effectiveness of 80-100% in adult ticks 24 hr post-application. In field, the LC90 of 119 juveniles of S. websteri in oil emulsions of J. virginiana at 33% on domestic dogs presented an accumulated a control effectiveness of 89% after 96 hr post-application. The combined application of J. virginiana and S. websteri could be a good alternative for the control of ticks. It was observed that the time of contact and the type of vegetable oil were crucial factors to increase the effectiveness of control.Although their control is based on chemical products, the infestations by ticks (Ixodes scapularis Say) are causing great losses and damages in the livestock production worldwide. In this study, the survival of the entomopathogenic nematodes Heterorhabditis bacteriophora, Steinernema carpocapsae and Steinernema websteri in vegetal oil suspension at concentrations of 13% and 33% and their effectiveness to control ticks at concentrations of 50 ± 5 and 100 ± 10 nematodes in oil suspensions of Cymbopogon citratus, Pelargonium sp, Juniperus virginiana, Rosa sp, and Mentha piperita were evaluated in lab conditions. In field conditions, the Lethal Concentration (LC90) of S. websteri in oil suspensions of J. virginiana and C. citratus in dogs infested with ticks was evaluated. In the laboratory, it was found that an oil emulsion of C. citratus and J. virginiana at 13% maintained the survival of S. carpocapsae, H. bacteriophora and S. websteri from 55% to 60% for a period of 96 hr. The combination of the S. websteri nematode with 50 or 100 nematodes in oil emulsions of J. virginiana at 33% presented a control effectiveness of 80­100% in adult ticks 24 hr post-application. In field, the LC90 of 119 juveniles of S. websteri in oil emulsions of J. virginiana at 33% on domestic dogs presented an accumulated a control effectiveness of 89% after 96 hr post-application. The combined application of J. virginiana and S. websteri could be a good alternative for the control of ticks. It was observed that the time of contact and the type of vegetable oil were crucial factors to increase the effectiveness of control.

New Scheme of Intermittent Benznidazole Administration in Patients Chronically Infected with Trypanosoma cruzi: a Pilot Short-Term Follow-Up Study with Adult Patients.

There is a clinical need to test new schemes of benznidazole administration that are expected to be at least as effective as the current therapeutic scheme but safer. This study assessed a new scheme of benznidazole administration in chronic Chagas disease patients. A pilot study with intermittent doses of benznidazole at 5 mg/kg/day in two daily doses every 5 days for a total of 60 days was designed. The main criterion of response was the comparison of quantitative PCR (qPCR) findings prior to and 1 week after the end of treatment. The safety profile was assessed by the rate of suspensions and severity of adverse effects. Twenty patients were analyzed for safety, while qPCR was tested for 17 of them. The average age was 43 ± 7.9 years; 55% were female. Sixty-five percent of treated subjects showed detectable qPCR results prior to treatment of 1.45 (0.63 to 2.81) and 2.1 (1.18 to 2.78) parasitic equivalents per milliliter of blood (par.eq/ml) for kinetoplastic DNA (kDNA) qPCR and nuclear repetitive sequence satellite DNA (SatDNA) qPCR, respectively. One patient showed detectable PCR at the end of treatment (1/17), corresponding to 6% treatment failure, compared with 11/17 (65%) patients pretreatment (P = 0.01). Adverse effects were present in 10/20 (50%) patients, but in only one case was treatment suspended. Eight patients showed mild adverse effects, whereas moderate reactions with increased liver enzymes were observed in two patients. The main accomplishment of this pilot study is the promising low rate of treatment suspension. Intermittent administration of benznidazole emerges a new potential therapeutic scheme, the efficacy of which should be confirmed by long-term assessment posttreatment.

[Portosystemic shunt in a normal liver causing confusional states]. / Shunt porto-sistémico congénito en hígado no cirrótico como causante de síndrome confusional agudo reiterado: Report of one case.

Portosystemic shunts are rare vascularization disorders, and an uncommon cause of confusional states. We report an 87-year-old male with a previously normal cognitive status who was repeatedly admitted for sudden symptoms of disorientation and functional limitation. The patient had high ammonium levels which lead to the suspicion of the presence a portosystemic shunt, even in the absence of pre-existing liver disease. A contrast enhanced computed tomography of the abdomen confirmed the presence an abnormal communication of the right portal vein with the suprahepatic veins. The communication was embolized and the confusional states of the patient subsided.

Predictors of response and relapse in patients with idiopathic membranous nephropathy treated with tacrolimus.

BACKGROUND: Although tacrolimus is recommended by KDIGO Clinical Practice Guideline for Glomerulonephritis for the treatment of idiopathic membranous nephropathy (MN), little is known about factors that influence response and relapse of the disease after tacrolimus therapy. METHODS: Multicentre study that collected 122 MN patients with nephrotic syndrome and stable renal function treated with tacrolimus. Duration of treatment was 17.6 ± 7.2 months, including a full-dose and a tapering period. RESULTS: The percentage of remission was 60, 78 and 84% after 6, 12 and 18 months of treatment, respectively. The amount of proteinuria at baseline significantly predicted remission, the lower the baseline proteinuria the higher the probability of remission. Only 10 patients (8%) received concomitantly corticosteroids, and their rate of remission was similar (80% at 18 months). Among responders, 42% achieved complete remission (CR) and 58% partial remission (PR). Almost half (44%) of the responder patients relapsed. The amount of proteinuria at the onset of tacrolimus tapering was significantly higher in relapsing patients. By multivariable analysis, the presence of a PR versus CR at the onset of tacrolimus tapering and a shorter duration of the tapering period significantly predicted relapses. Tolerance was good and the number of adverse events low. CONCLUSIONS: Tacrolimus monotherapy is an effective and safe option for the treatment of MN with stable renal function. Relapses are frequent in patients with PR and can be partially prevented by a longer tapering period.

Investigating the relationship between multiple sclerosis disability and driving performance: A comparative study of the multiple sclerosis functional composite and expanded disability status scale.

INTRODUCTION: Multiple Sclerosis (MS) can affect the ability to perform complex tasks such as driving. The Expanded Disability Status Scale (EDSS) overlooks cognitive deficits crucial for driving. We investigated the relationship between the Multiple Sclerosis Functional Composite (MSFC), which includes cognitive assessment, and EDSS in relation to driving performance. METHODS:  This exploratory study involved 30 MS patients (mean EDSS 2.4 ± 2.0) and 15 healthy controls. We correlated the results of the EDSS, MSFC, and driving performance tests, namely the Two-Hand Coordination Test (2HAND) and the Speed Anticipation Reaction Test (SART). RESULTS: Patients did not differ from the healthy controls regarding age, sex, and driving experience. However, they exhibited lower mean Z-scores in MSFC, particularly in motor domains, but not in cognitive function. The mean Z-score for the 25-foot Walk test was -0.42 in patients compared to -0.04 in controls. For the 9-hole Peg Test, it was 0.17 in patients versus 1.47 in controls. Patients had a mean total error time of 19.7 seconds for both hands in the 2HAND test, compared to 7.7 seconds in controls. In MS patients, the MSFC and EDSS significantly correlated with SART and 2HAND components. While upper limb function (9-HPT) did not correlate with 2HAND, cognitive function (PASAT) did correlate with the number of 2HAND errors, indicating that cognitive dysfunction impacts driving performance more than physical dysfunction. CONCLUSION: The MSFC may provide valuable insights into the driving abilities of MS patients, potentially offering advantages over the EDSS in predicting driving performance. Further research with larger, more diverse populations across various driving environments is necessary to validate these findings.

Effect of preoperative exercise on vascular caliber and maturation of arteriovenous fistula: the physicalfav trial, a randomized controlled study.

BACKGROUND AND OBJECTIVES: Autologous arteriovenous fistula (AVF) is the best vascular access for hemodialysis. Distal forearm radiocephalic fistula is the best option, although the primary failure rate ranges from 20% to 50%. The main objective of the PHYSICALFAV trial was to evaluate the effect of preoperative isometric exercise on vascular caliber, percentage of distal arteriovenous fistula, and primary failure rate. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: The PHYSICALFAV trial (NCT03213756) is an open-label, multicenter, prospective, randomized, controlled trial (RCT). A total of 138 patients were randomized 1:1 to the exercise group (exercises combining a handgrip device and an elastic band for 8 weeks) or the control group (no exercise) and followed up with periodic Doppler ultrasound (DU) examinations. RESULTS: After 8 weeks of preoperative isometric exercise, in the exercise group, significant increases were detected in venous caliber (2.80 ± 0.95 mm vs 3.52 ± 0.93 mm [p < 0.001]), arterial caliber (2.61 ± 0.82 mm vs 2.74 ± 0.80 mm [p = 0.008]), arterial peak systolic velocity (66.34 ± 19.2 cm/s vs 71.03 ± 21.5 cm/s [p 0.043]), and maximum strength (28.35 ± 9.16 kg vs 32.68 ± 10.8 kg [p < 0.001]). Distal radiocephalic fistulas were performed in 75% of the exercise group patients compared with 50.8% in the control group (p = 0.030). The global primary failure rate was very low in both groups (7% exercise group vs 14% control group [p = 0.373]). CONCLUSION: Isometric preoperative exercise can improve vascular caliber and increase the possibility of performing distal arteriovenous fistula, with no significant differences in primary failure rate.

Ex vivo characterization of Breg cells in patients with chronic Chagas disease.

Despite the growing importance of the regulatory function of B cells in many infectious diseases, their immunosuppressive role remains elusive in chronic Chagas disease (CCD). Here, we studied the proportion of different B cell subsets and their capacity to secrete IL-10 ex vivo in peripheral blood from patients with or without CCD cardiomyopathy. First, we immunophenotyped peripheral blood mononuclear cells from patients according to the expression of markers CD19, CD24, CD38 and CD27 and we showed an expansion of total B cell and transitional CD24highCD38high B cell subsets in CCD patients with cardiac involvement compared to non-infected donors. Although no differences were observed in the frequency of total IL-10 producing B cells (B10) among the groups, CCD patients with cardiac involvement showed an increased proportion of naïve B10 cells and a tendency to a higher frequency of transitional B10 cells compared to non-infected donors. Our research demonstrates that transitional B cells are greatly expanded in patients with the cardiac form of CCD and these cells retain the ability to secrete IL-10. These findings provide insight into the phenotypic distribution of regulatory B cells in CCD, an important step towards new strategies to prevent cardiomyopathy associated with T. cruzi infection.

IgE antibodies against Trypanosoma cruzi arginine kinase in patients with chronic Chagas disease.

Arginine kinase (AK) is an enzyme present in various invertebrates, as well as in some trypanosomatids such as T. cruzi, the etiological agent that causes Chagas disease. In invertebrates, this protein acts as an allergen inducing an IgE-type humoral immune response. Since AK is a highly conserved protein, we decided to study whether patients with chronic Chagas disease (CCD) produce specific antibodies against T. cruzi AK (TcAK). Plasma from patients with CCD, with and without cardiac alterations and non-infected individuals were evaluated for the presence of anti-TcAK IgG and IgE antibodies by ELISA, including detection of specific IgG subclasses. Our results showed that the levels of specific anti-TcAK IgG and IgE were different between infected and non-infected individuals, but comparable between those with different clinical manifestations. Interestingly, anti-TcAK IgG4 antibodies associated with IgE-mediated allergenic processes were also increased in CCD patients. Finally, we found that several of the predicted B cell epitopes in TcAK matched allergenic peptides previously described for its homologues in other organisms. Our results revealed for the first time a parasite's specific IgE antibody target and suggest that TcAK could contribute to delineate an inefficient B cell response by prompting a bias towards a Th2 profile. These findings also shed light on a potential allergenic response in the context of T. cruzi infection.

Predicting conversion to multiple sclerosis by assessing cognitive impairment in radiologically isolated syndrome.

Up to a third of patients with radiologically isolated syndrome (RIS) exhibit lower-than-expected cognitive performances in neuropsychological evaluations, but the relationship between cognitive impairment (CI) and quantitative magnetic resonance (MRI) measures has not been stablished. Furthermore, the prognostic role of CI in RIS for conversion to MS is currently unknown. We assessed 17 patients with RIS and 17 matched healthy controls (HC) with a neurophychological battery and a 3T MRI. Six patients (35,3%) fulfilled our criterion for CI (scores 2 SDs below the mean of HC in at least two cognitive tests) (ci-RIS). The ci-RIS subgroup showed lower values of normalized brain and gray matter volumes when compared to HC. After a median follow-up time of 4.5 years, the ci-RIS subgroup presented a higher conversion rate to MS, suggesting that CI might be an independent risk factor for conversion to MS.

Correction to: Nifurtimox versus benznidazole or placebo for asymptomatic Trypanosoma cruzi infection (Equivalence of Usual Interventions for Trypanosomiasis - EQUITY): study protocol for a randomised controlled trial.

Following publication of the original article [1], the authors notified us of a few requested editions that were not implemented adequately during proofing. The publisher apologizes for the inconvenience caused to our authors and readers.

Nifurtimox versus benznidazole or placebo for asymptomatic Trypanosoma cruzi infection (Equivalence of Usual Interventions for Trypanosomiasis - EQUITY): study protocol for a randomised controlled trial.

BACKGROUND: Either benznidazole (BZN) or nifurtimox (NFX) is recommended as equivalent to treat Trypanosoma cruzi infection. Nonetheless, supportive data from randomised trials is limited to individuals treated with BZN in southern cone countries of Latin America. METHODS: The goal of this randomised, concealed, blind, parallel-group trial is to inform the trypanocidal efficacy and safety of NFX and its equivalence to BZN among individuals with T. cruzi positive serology (TC+). Eligible individuals are TC+, 20-65 years old, with no apparent symptoms/signs or uncontrolled risk factors for cardiomyopathy and at negligible risk of re-infection. Consenting individuals (adherent to a 10-day placebo run-in phase) receive a 120-day BID blinded treatment with NFX, BZN or matching placebo (2:2:1 ratio). The four active medication arms include (1) a randomly allocated sequence of 60-day, conventional-dose (60CD) regimes (BZN 300 mg/day or NFX 480 mg/day, ratio 1:1), followed or preceded by a 60-day placebo treatment, or (2) 120-day half-dose (120HD) regimes (BZN 150 mg/day or NFX 240 mg/day, ratio 1:1). The primary efficacy outcome is the proportion of participants testing positive at least once for up to three polymerase chain reaction (PCR) assays (1 + PCR) 12-18 months after randomisation. A composite safety outcome includes moderate to severe adverse reactions, consistent blood marker abnormalities or treatment abandons. The trial outside Colombia (expected to recruit at least 60% of participants) is pragmatic; it may be open-label and not include all treatment groups, but it must adhere to the randomisation and data administration system and guarantee a blinded efficacy outcome evaluation. Our main comparisons include NFX groups with placebo (for superiority), NFX versus BZN groups and 60CD versus 120HD groups (for non-inferiority) and testing for the agent-dose and group-region interactions. Assuming a 1 + PCR ≥ 75% in the placebo group, up to 25% among BZN-treated and an absolute difference of up to ≥ 25% with NFX to claim its trypanocidal effect, 60-80 participants per group (at least 300 from Colombia) are needed to test our hypotheses (80-90% power; one-sided alpha level 1%). DISCUSSION: The EQUITY trial will inform the trypanocidal effect and equivalence of nitroderivative agents NFX and BZN, particularly outside southern cone countries. Its results may challenge current recommendations and inform choices for these agents. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02369978 . Registered on 24 February 2015.

Digoxin and prognosis of heart failure in older patients with preserved ejection fraction: Importance of heart rate. Results from an observational and multicenter study.

BACKGROUND: The value of digoxin in heart failure (HF) remains controversial, particularly in patients with preserved ejection fraction (HFpEF). This study evaluated the 1-year risk of events after digoxin treatment for acute heart failure (AHF) in patients >70 years old with HFpEF. METHODS: 1833 patients were included in this analysis (mean age, 82 years). The main endpoints were all-cause death and the composite of death and/or HF re-admission within 1 year. Cox regression analysis was used to evaluate the association between digoxin treatment and prognosis. RESULTS: 401 patients received digoxin treatment; of these, 86% had atrial fibrillation. The mean baseline heart rate was 86 ±â€¯22 bpm. At the 1-year follow-up, 375 patients (20.5%) died and 684 (37.3%) presented composite endpoints. Patients treated with digoxin showed higher rates of death (3.21 vs. 2.44 per 10 person-years, p = .019) and composite endpoint (6.72 vs. 5.18 per 10 person-years, p = .003). After multivariate adjustment, digoxin treatment remained associated with increased risks of death (HR = 1.46, 95% CI: 1.16-1.85, p = .001) and the composite endpoint (HR = 1.35, 95% CI: 1.13-1.61, p = .001). A distinctive prognostic effect of digoxin was found across the heart rate continuum; the risks for both endpoints were higher at lower heart rates and neutral at higher heart rates (p of the interactions = 0.007 and 0.03, respectively). CONCLUSIONS: In older patients with HFpEF discharged after AHF, digoxin treatment was associated with increased mortality and/or re-admission, particularly in patients with lower heart rates.

An alternative method for the synthesis of competitor RNA transcripts useful for specific detection and quantitation of dengue virus serotype 2 genome and replicative intermediate RNA.

The development of a quantitative-competitive reverse transcription-PCR (RT-PCR) assay to quantify dengue virus (DEN) genome (vRNA) and its replicative intermediate RNA (vRI) is described. A highly conserved region located on the DEN capsid-premembrane genes was used to produce a competitor RNA molecule which contains an internal deletion of 70 nucleotides. The competitor provides a suitable internal control useful to quantify viral RNA from all four dengue virus (DEN 1-4) serotypes. The detection limit of the assay was found to be 100 copies per reaction. This is a rapid, simple, sensitive, inexpensive and easy method for quantitation of DEN RNA species.

Chagas cardiomyopathy associated with serological cure after trypanocidal treatment during childhood.

Chagas disease is a chronic parasitological disease, which could cause cardiac manifestations in approximately one-third of affected individuals. Benznidazole and nifurtimox are used to treat this parasitological infection caused by Trypanosoma cruzi. Conventionally, the criterion for cure is consistently negative serological tests after treatment. We report a case of a patient who was treated when she was 13 years old and achieved T. cruzi negative seroconversion but developed Chagas disease cardiomyopathy as an adult.