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Invasive species pose a threat to the ecological balance of the ecosystems they invade by altering local host-pathogen dynamics. To investigate these relationships and their potential consequences, we examined the prevalence and genetic diversity patterns of Trypanosomatidae, Lipotrophidae, and Nosematidae in a collection of sympatric isolates of the invasive hornet Vespa velutina and local Hymenoptera from two recently colonized areas: Europe and South Korea. Data were gathered through PCR amplification and massive parallel sequencing, and analyses were conducted using population genetics tools. Parasite prevalences showed substantial variation depending on (i) the parasite family (Trypanosomatidae and Nosematidae were the most and less prevalent, respectively), (ii) location (e.g. Galicia displayed the highest pooled values), (iii) the season (highest in spring for Trypanosomatidae and Lipotrophidae), and (iv) the host. V. velutina exhibited significantly lower parasite occurrence than native Hymenoptera across all parasite families (consistent with the enemy release hypothesis), although this difference was less pronounced during the periods of heightened predatory activity, suggestive of trophic transmission. Parasite species displayed significant genetic differentiation between European and South Korean isolates, yet no differentiation was observed across hosts, suggesting that all Hymenoptera are exposed to a common local pathogen population. There was no indication that V. velutina acted as a carrier of foreign parasites to the invaded territories., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Radiotherapy (RT) is the gold standard for solitary plasmacytomas (SP) with great local control. The influence of radiotherapy as well as factors on multiple myeloma (MM) progression is unknown., Materials and Methods: We present a retrospective study of 27 patients with SP (bone-SBP- and extramedullary-SEP-), treated since 1995 to 2021. We aim to analyze prognostic factors affecting local control and progression to MM in patients treated with radiotherapy (RT)., Results: Mean age was 57.3 years. 22 were SBP and 5 SEP. 13 patients were treated with definitive RT, and 14 with a combination of RT and systemic treatment and/or surgery. Local control was observed in 91.5% of cases. 28% experienced progression to MM. With a median follow up of 61.4 months [39.5, 121.6], 5-years MM-free-survival was 81 ± 8%; no individuals progressed further 50 months since diagnosis. Large tumor bulk (> 5 cm) and type (SBP 36% vs . SEP 0%) were associated with progression. Progression was not affected by doses greater than 46 Gy and/or surgery. An immunophenotype different from IgG kappa was predictive of less progression (p = 0.031) in Cox regression analysis adjusted for age, RT dose and tumor bulk > 5 cm. Patients with positron emission tomography-computed tomography (PET-CT) staging showed less MM progression, without statistical differences., Conclusion: RT achieves more than 90% of local control. The immunophenotype IgG kappa showed more risk of progression to MM. Initial staging with PET-CT seems to lead to a better identification of SP. The inclusion of bad prognosis patients in clinical trials would determine the role of adjuvant chemoimmunotherapy in SP treatment., Competing Interests: Conflict of interests: The authors have no relevant financial or non-financial interests to disclose. All authors have approved the final article., (© 2024 Greater Poland Cancer Centre.)

Purpose: To analyze the influence of embryo storage on reproductive and neonatal results in patients undergoing in vitro fertilization (IVF) treatment., Methods: PubMed, Embase, Cochrane Central Register of Controlled Trials, and BioMed Central databases were searched from inception up to June 2024 for studies comparing reproductive and neonatal outcomes in patients undergoing frozen embryo transfer within 12 months from embryo storage versus more than 12 months after embryo storage. Data were pooled by meta-analysis using a random effects model., Results: A total of 16 studies, involving 233,315 embryos were included. Patients undergoing frozen embryo within 12 months from embryo storage were associated with higher rates of live birth (OR 1.17, 95% CI 1.09-1.26, I 2  = 78%) biochemical pregnancy (OR 1.26, 95% CI 1.08-1.47, I 2  = 77.8%) clinical pregnancy (OR 1.24, 95% CI 1.12-1.38, I 2  = 86.3%) and multiple pregnancy rate (OR 1.26, 95% CI 1.03-1.55, I 2  = 69%). No significant differences between groups were shown in terms of survival rate (OR 1.52, 95% CI 0.65-3.58, I 2  = 98.5%), miscarriage (OR 1.08, 95% CI 0.91-1.27, I 2  = 77%), implantation rate (OR 1.17, 95% CI 0.90-1.52, I 2  = 91.7%) and ectopic pregnancy (OR 0.98, 95% CI 0.80-1.20, I 2  = 0%). In addition, prolonged embryo storage was not associated with higher rates of preterm delivery (OR 0.86, 95% CI 0.67-1.09, I 2  = 8.3%), low weight at birth (OR 1.10, 95% CI 0.88-1.38, I 2  = 24.3%) or congenital malformations (OR 0.90, 95% CI 0.65-1.25, I 2  = 0.8%)., Conclusion: Prolonged embryo storage over 12 months is associated with lower rates of live birth, biochemical pregnancy, clinical pregnancy, and multiple pregnancy. However, important covariates such as reasons for delay of transfer, embryo quality, and improper handling of embryos could not be ruled out as causes of this reduction. Given these limitations, these conclusions should be viewed with caution., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Left atrial peak systolic strain (LA-PSS) imaging is an emerging index of left atrial function, and it was shown to be decreased in heart failure with preserved ejection fraction (EF). We aimed to determine whether LA-PSS could be used as an additional diagnostic parameter to current existing guidelines for the presence of left ventricle diastolic dysfunction (LVDD)., Materials and Methods: A total of 190 consecutive adult patients with cardiovascular risk factors and normal left ventricle EF with no prior history of heart failure were included in the study. Speckle tracking software was used to study ventricular parietal deformity, left ventricle global longitudinal systolic strain, and LA-PSS., Results: The median left ventricle global longitudinal systolic strain was -19%, with a significant difference ( P < 0.001) between patients with normal diastolic function versus those with LVDD. The median LA-PSS was 33% (30% to 38%) ( P < 0.001). Most patients (61%) had grade 1 atrial dysfunction based on PSS (range 24%-35%). The analysis of the area under the receiver operating characteristic curve of the LA-PSS as a potential indicator pathway of LVDD was 67% [95% confidence interval (CI), 62-72], and 75% (95% CI, 70-80), when the indeterminate pattern was included. The decreased LA-PSS made it possible to reclassify patients with an indeterminate pattern of diastolic function in 96% of cases., Conclusions: These results support the potential role of LA-PSS as an additional parameter for the diagnosis of LVDD in patients with normal EF, and may be integrated into the guidelines for routine evaluation of patients., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Guillain-Barré syndrome (GBS) frequently leads to respiratory failure and autonomic dysfunction, resulting in approximately one-third of patients requiring mechanical ventilation., Objective: This study aimed to identify clinical predictors for mechanical ventilation in patients with GBS., Methods: This research was conducted from 2010 to 2021 using registries from a tertiary hospital in an upper middle-income Latin American country. Participants were categorized into two groups based on their ventilation status. Demographic data were collected, and independent predictors of the need for mechanical ventilation were determined through multivariate logistic regression analysis., Results: Dysautonomic events occurred in 36% of the patients, with 17% requiring mechanical ventilation; the average duration of intubation was 1.16 ± 3.18 days. The multivariate analysis indicated that bulbar dysfunction significantly increased the likelihood of requiring mechanical ventilation by 19-fold (OR 18.67, 95% CI 5.85-59.42), followed by ophthalmoplegia, which increased the likelihood by sixfold (OR 5.68, 95% CI 1.28-25.19)., Conclusion: Bulbar dysfunction, dysautonomia, and lower Medical Research Council (MRC) scores were significant predictors of the need for mechanical ventilation in hospitalized GBS patients. These findings support the need for close monitoring and early admission to the intensive care unit (ICU) admission for at-risk patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Rodríguez-Méndez, Briseño-Ramírez, Rivas-Ruvalcaba, Solis-Estrada, Alcázar-García, Díaz-Ramírez, Lira-Jaime, Sánchez-Román and Zúñiga-Ramírez.)

Background: There is a global tendency to emphasize the prevention and early diagnosis of diseases that have a great impact on public health. Atrial fibrillation (AF) has a prevalence affecting 1.5-2% of the general population. Certain variables of the P wave allow us to identify and stratify patients at risk of developing AF., Materials and Methods: This is an observational, descriptive, and longitudinal study to determine the applicability of the electrocardiographic (ECG) morphology, voltage, and P wave duration (MVP) risk score to predict the development of AF in consecutive patients with systemic hypertension (SH) in an initial follow-up of 12 months., Results: Initially, 104 patients were included, of whom 12 died during follow-up and 17 did not attend subsequent checkups during the COVID-19 pandemic; therefore, they were excluded. The study patients were 75, of whom AF was detected in 25 patients (33%). The average duration of the P wave was 120 ± 26 ms, the average voltage was 0.1 ± 0.5 Mv. The high-risk MVP ECG score had an [area under the curve, 0.69; 95% confidence intervals (CI), 0.59-0.79] and demonstrated a specificity and a positive predictive value of 100%, a negative predictive value of 76%, and a sensitivity of 40% for predicting the development of AF., Conclusions: The present study establishes for the first time that SH patients who possess a high-risk MVP ECG score have a significantly higher incidence of developing AF. The high-risk MVP Score has a specificity and a positive predictive value of 100% and a high negative predictive value with a moderate sensitivity for the prediction of the development of AF in SH patients., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Agave lechuguilla is a widely distributed plant in arid ecosystems. It has been suggested that its microbiome is partially responsible for its great adaptability to the oligotrophic environments of the Chihuahuan Desert. To lead the recruitment of beneficial rhizobacteria, the root exudates are essential; however, the amino acids contained within these compounds had been largely overlooked. Thus, we investigated how the variations of amino acids in the rhizosphere at different growth stages of A. lechuguilla affect the rhizobacterial community composition, its functions, and activity of the beneficial bacteria. In this regard, it was found that arginine and tyrosine were related to the composition of the rhizobacterial community associated to A. lechuguilla, where the most abundant genera were from the phylum Proteobacteria and Bacteroidetes. Moreover, Firmicutes was largely represented by Bacillus in the phosphorus-mineralizing bacteria community, which may indicate its great distribution and versatility in the harsh environments of the Chihuahuan Desert. In contrast, we found a high proportion of Unknown taxa of nitrogen-fixing bacteria, reflecting the enormous diversity in the rhizosphere of these types of plants that remains to be explored. This work also reports the influence of micronutrients and the amino acids methionine and arginine over the increased activity of the nitrogen-fixing and phosphorus-mineralizing bacteria in the rhizosphere of lechuguillas. In addition, the results highlight the multiple beneficial functions present in the microbiome that could help the host to tolerate arid conditions and improve nutrient availability., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: The Tpeak-Tend interval of the T wave has emerged as a new electrocardiographic marker of increased transmural dispersion of ventricular repolarization. We aimed to determine the presence of cardiac conduction system disorders in patients with systemic arterial hypertension (SAH) who have altered Tpeak-Tend interval of the T wave., Methods: The 67 patients with SAH were divided into two groups. Those with prolonged (≥ 77 ms) Tpeak-Tend intervals, 21 (31%) patients were in the study group. Those with normal (< 77 ms) Tpeak-Tend intervals, 46 (69%) patients were in the control group. Alteration of ventricular repolarization manifested as a prolongation of the Tpeak-Tend interval was detected by computerized electrocardiographic analysis tools., Results: The median value of QRS complex duration was significantly wider in the study group as compared to the control group (110 ± 12 ms vs. 94 ± 8 ms p < 0.001). There was a significantly greater incidence of left anterior hemiblock in the study group (14% vs. 0% p < 0.04). The median value of the QTc interval was significantly greater in the study group (440 ± 26 vs. 422 ± 15 p < 0.01). There was a significantly greater incidence of patients with prolonged QTc interval in the study group (33% vs. 11% p < 0.02). The median value of the Tpeak-Tend interval was significantly greater in the study group (84 ± 5 ms vs. 65 ± 4 ms p < 0.001), as well as, the Tpeak-Tend/QTc ratio in the study group (0.19 ± 0.1 vs. 0.16 ± 0.1 p < 0.001)., Conclusion: There is a significantly greater ventricular repolarization disorders and abnormalities of the cardiac conduction system in SAH patients who possess altered Tpeak-Tend interval of the T wave., (Copyright: © 2023 Permanyer.)

Invasive species contribute to deteriorate the health of ecosystems due to their direct effects on native fauna and the local parasite-host dynamics. We studied the potential impact of the invasive hornet Vespa velutina on the European parasite-host system by comparing the patterns of diversity and abundance of pathogens (i.e. Microsporidia: Nosematidae; Euglenozoa: Trypanosomatidae and Apicomplexa: Lipotrophidae) in European V. velutina specimens with those in the native European hornet Vespa crabro, as well as other common Hymenoptera (genera Vespula, Polistes and Bombus). We show that (i) V. velutina harbours most common hymenopteran enteropathogens as well as several new parasitic taxa. (ii) Parasite diversity in V. velutina is most similar to that of V. crabro. (iii) No unambiguous evidence of pathogen release by V. velutina was detected. This evidence together with the extraordinary population densities that V. velutina reaches in Europe (around of 100,000 individuals per km 2 per year), mean that this invasive species could severely alter the native pathogen-host dynamics either by actively contributing to the dispersal of the parasites and/or by directly interacting with them, which could have unexpected long-term harmful consequences on the native entomofauna.

Due to the lack of prospective, randomized, controlled clinical studies on inflammation and cardiovascular involvement, the exact mechanism of cardiac injury among patients with Coronavirus Disease 2019 (COVID-19) still remains uncertain. It was demonstrated that there is a high and significantly positive linear correlation between troponin T and plasma high-sensitivity C-reactive protein levels, biomarkers of cardiac injury and systemic inflammation, respectively. Cardiac injury and inflammation is a relatively common association among patients hospitalized with COVID-19, and it is related to higher risk of in-hospital mortality. In our literature search, we identified several potential mechanisms of myocardial tissue damage, namely, coronavirus-associated acute myocarditis, angiotensin-converting enzyme 2 receptor binding affinity to the virus Spike protein, increased cytokine secretion, and hypoxia-induced cardiac myocyte apoptosis. Elucidation of the disease pathogenesis and prospective histopathological studies are crucial for future proper treatment in case of renewed outbreaks. Of interest is that with hundred of thousands of bodies available for autopsy studies, no prospective investigation has been reported so far. Strong efforts and continued research of the cardiovascular complications and identification of risk factors for poor prognosis in COVID-19 are steadily needed. The high morbidity and mortality of COVID-19, its monumental economic burden and social impact, the despair of a new pandemic outbreak, and the thread of potential utilization of novel severe acute respiratory syndrome coronavirus 2 as biologic weapons make it a preponderant necessity to better comprehend the therapeutic management of this lethal disease. Emerging as an acute infectious disease, COVID-19 may become a chronic epidemic because of genetic recombination. Therefore, we should be ready for the reemergence of COVID-19 or other coronaviruses., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Atrial fibrillation (AF) is the most common arrhythmia in middle-aged athletes. Physical exercise performed in a regular basis has been shown to be beneficial for cardiovascular health. Moderate physical exercise, aside from producing a nice, peaceful and well-being sensation, has been associated with a reduced risk of AF. However, more strenuous endurance exercise, like the one experiencing marathon runners, seems to increase the risk of AF in healthy athletes without organic heart disease. On the other hand, low physical activity was found to be a risk factor for the appearance of AF. Nevertheless, the relationship of exercise to AF is complex, influenced by the intensity and the duration of the physical activity, and seems to have a U-shaped relationship with the greatest levels of physical activity possibly increasing AF incidence. There is cumulative data associating moderate physical activity to reduced AF incidence, hence physicians should recommend moderate exercise training to patients with AF. This may not only reduce AF risk, but would also contribute to an overall cardiovascular benefit. However, since there is also important data suggesting significant increased incidence of AF in elite athletes with long-term endurance physical activity, it may be a serious concern to go to the extreme. In most things in life it is much better and wiser to be well balanced, always in equilibrium.

Background: The fragmented QRS complex (FQRS) was found to be associated to malignant ventricular arrhythmias and sudden death in patients with hypertrophic cardiomyopathy and other entities. There is scant data available correlating the presence of FQRS with QT interval prolongation in patients with ischemic heart disease (IHD)., Methods: A descriptive, retrospective, cross-sectional study was performed in 123 patients with IHD to analyze and correlate the presence of FQRS with QT interval prolongation in the conventional 12-leads electrocardiogram in patients with documented chronic IHD., Results: There were 62% male patients. The mean age was 63.8±12.6 years. Thirty six (44%) patients had fragmented QRS (64% men and 36% women). The duration of QT and QTc, the mean values were 413±59ms, and 463±67ms, respectively. Of the 36 patients with FQRS, 23 patients have prolongation of the QTc interval, and 13 patients did not present it. Of the 45 patients without FQRS, 21 of them have prolongation of the QTc interval, and 24 patients did not have it. These data resulted in a sensitivity of 52% with a moderate SnNout, a specificity of 65% with moderate SpPin, a positive predictive accuracy of 64%, a negative predictive accuracy of 53%. These data resulted in a prevalence of 54%., Conclusion: the presence of FQRS in the ECG has a moderate sensitivity and specificity, as well as, moderate negative and positive predictive value of the existence of QT interval prolongation in patients with ischemic heart disease., (Copyright © 2019, Medical University Publishing House Craiova.)

The mechanism of sudden cardiac death (SCD) in patients with nonischemic dilated cardiomyopathy (NIDCM) is mostly due to sustained ventricular tachycardia and ventricular fibrillation. The clinical guidelines for the therapeutic management of this set of patients are mostly based on left ventricular ejection fraction value which has a low specificity to differentiate the risk of SCD from the risk of mortality associated with heart failure or other comorbidities. Moreover, since SCD can occur in patients with normal or mildly depressed ejection fraction, it is necessary to identify new markers to improve the prognostic stratification of SCD. Several studies that analyzed the ventricular arrhythmia substrate found that myocardial fibrosis plays an important role in the genesis of ventricular arrhythmias in patients with NIDCM. The surrounding zone of the area of fibrosis is a heterogeneous medium, where tissue with different levels of fibrosis coexists, resulting in both viable and nonviable myocardium. This myocardial fibrosis may constitute a substrate for ventricular arrhythmias, where slow and heterogeneous conduction may favor the genesis of reentry mechanism increasing the chance to develop sustained ventricular tachycardia or ventricular fibrillation. Therefore, the evaluation of ventricular fibrosis by late gadolinium enhancement (LGE) cardiac magnetic resonance imaging has been suggested as an indicator for SCD risk stratification. Indeed, LGE in patients with NIDCM is associated with increased risk of all-cause mortality, heart failure hospitalization, and SCD. Detection of myocardial fibrosis as LGE by cardiac magnetic resonance imaging can be considered as a useful pathway of prediction of malignant ventricular arrhythmias since it has excellent prognostic characteristics and may help guide risk stratification and management in patients with NIDCM.

The development of atrial fibrillation (AF) during the course of the evolution of heart failure (HF) worsens the clinical outcomes and the prognosis accounting for an enormous economic burden on healthcare. AF is considered to be an independent predictor of morbidity and mortality increasing the risk of death and hospitalization in 76% in HF patients. Despite the good clinical results obtained with conventional pharmacological agents and different new drugs, the optimal medical treatment can fail in the intention to improve symptoms and quality of life of HF patients with severe left ventricular dysfunction and AF with uncontrolled ventricular rate. Therefore, the necessity to utilize cardiac devices to perform cardiac resynchronization therapy (CRT), or the need to use catheter ablation, or both, emerges facing the failure of optimal medical treatment in order to achieve hemodynamic improvement. Some of these AF patients will require atrio-ventricular nodal (AVN) catheter ablation in order to restore 100% CRT functionality and improvements in clinical outcomes. It is hard to imagine that the deliberate destruction of a natural and normally functional specialized tissue of the main conduction system of the heart would do any good. However, in the presence of AF with rapid ventricular response due to normal conduction through the AV node in HF patients, the fast ventricular rate can cause deleterious consequences in the clinical outcome. Moreover, there are interesting published data which will be analyzed in this manuscript documenting significant acute and long-term improvement in left ventricular function, symptoms, exercise tolerance, clinical outcomes, and quality of life in selected HF patients with paroxysmal and persistent drug-refractory AF who have undergone AVN ablation and permanent pacemaker implantation.

The processes whereby ecological networks emerge, persist and decay throughout ecosystem development are largely unknown. Here we study networks of plant and arbuscular mycorrhizal fungal (AMF) communities along a 120 000 year soil chronosequence, as they undergo assembly (progression) and then disassembly (retrogression). We found that network assembly and disassembly were symmetrical, self-reinforcing processes that together were capable of generating key attributes of network architecture. Plant and AMF species that had short indirect paths to others in the community (i.e. high centrality), rather than many direct interaction partners (i.e. high degree), were best able to attract new interaction partners and, in the case of AMF species, also to retain existing interactions with plants during retrogression. We then show using simulations that these non-random patterns of attachment and detachment promote nestedness of the network. These results have implications for predicting extinction sequences, identifying focal points for invasions and suggesting trajectories for restoration., (© 2018 John Wiley & Sons Ltd/CNRS.)

Substantial amounts of nutrients are lost from soils through leaching. These losses can be environmentally damaging, causing groundwater eutrophication and also comprise an economic burden in terms of lost agricultural production. More intense precipitation events caused by climate change will likely aggravate this problem. So far it is unresolved to which extent soil biota can make ecosystems more resilient to climate change and reduce nutrient leaching losses when rainfall intensity increases. In this study, we focused on arbuscular mycorrhizal (AM) fungi, common soil fungi that form symbiotic associations with most land plants and which increase plant nutrient uptake. We hypothesized that AM fungi mitigate nutrient losses following intensive precipitation events (higher amount of precipitation and rain events frequency). To test this, we manipulated the presence of AM fungi in model grassland communities subjected to two rainfall scenarios: moderate and high rainfall intensity. The total amount of nutrients lost through leaching increased substantially with higher rainfall intensity. The presence of AM fungi reduced phosphorus losses by 50% under both rainfall scenarios and nitrogen losses by 40% under high rainfall intensity. Thus, the presence of AM fungi enhanced the nutrient interception ability of soils, and AM fungi reduced the nutrient leaching risk when rainfall intensity increases. These findings are especially relevant in areas with high rainfall intensity (e.g., such as the tropics) and for ecosystems that will experience increased rainfall due to climate change. Overall, this work demonstrates that soil biota such as AM fungi can enhance ecosystem resilience and reduce the negative impact of increased precipitation on nutrient losses., (© 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.)

We report a survey of genetic variation at three coding loci in Giardia duodenalis of assemblages A and B obtained from stool samples of patients from Santiago de Compostela (Galicia, NW-Iberian Peninsula). The mean pooled synonymous diversity for assemblage A was nearly five times lower than for assemblage B (0.77%±0.30% and 4.14%±1.65%, respectively). Synonymous variation in both assemblages was in mutation-drift equilibrium and an excess of low-frequency nonsynonymous variants suggested the action of purifying selection at the three loci. Differences between isolates contributed to 40% and 60% of total genetic variance in assemblages A and B, respectively, which revealed a significant genetic structure. These results, together with the lack of evidence for recombination, support that (i) Giardia assemblages A and B are in demographic equilibrium and behave as two genetically isolated populations, (ii) infections are initiated by a reduced number of individuals, which may be genetically diverse and even belong to different assemblages, and (iii) parasites reproduce clonally within the host. However, the observation of invariant loci in some isolates means that mechanisms for the homogenization of the genetic content of the two diploid nuclei in each individual must exist., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Amiodarone is still the most potent antiarrhythmic drug in the prevention of life threatening ventricular arrhythmias and demonstrates a very low incidence of torsade de pointes. An unusual case of an 81-year-old woman who developed serious abnormalities of the conduction system of the heart and torsade des pointes during intravenous infusion of amiodarone for the treatment of paroxysmal atrial fibrillation is described. To the best of our knowledge, this is the first case showing an association of intravenous amiodarone-induced third degree atrioventricular block and extreme QT interval prolongation generating torsade des pointes in a patient with paroxysmal atrial fibrillation who required an implantable cardioverter-defibrillator. Currently, amiodarone is still one of the few remaining treatment options for the medical therapeutic management of serious ventricular arrhythmias and to reduce the incidence of atrial fibrillation without increasing mortality or sudden cardiac death rates in heart failure patients like our elderly present patient. Nevertheless, we have to keep in mind that intravenous amiodarone may generate serious abnormalities of the conduction system of the heart and lethal ventricular arrhythmias in certain patients.

Little is known about the response of arbuscular mycorrhizal fungal communities to ecosystem development. We use a long-term soil chronosequence that includes ecosystem progression and retrogression to quantify the importance of host plant identity as a factor driving fungal community composition during ecosystem development. We identified arbuscular mycorrhizal fungi and plant species from 50 individual roots from each of 10 sites spanning 5-120 000 yr of ecosystem age using terminal restriction fragment length polymorphism (T-RFLP), Sanger sequencing and pyrosequencing. Arbuscular mycorrhizal fungal communities were highly structured by ecosystem age. There was strong niche differentiation, with different groups of operational taxonomic units (OTUs) being characteristic of early succession, ecosystem progression and ecosystem retrogression. Fungal alpha diversity decreased with ecosystem age, whereas beta diversity was high at early stages and lower in subsequent stages. A total of 39% of the variance in fungal communities was explained by host plant and site age, 29% of which was attributed to host and the interaction between host and site (24% and 5%, respectively). The strong response of arbuscular mycorrhizal fungi to ecosystem development appears to be largely driven by plant host identity, supporting the concept that plant and fungal communities are tightly coupled rather than independently responding to habitat., (© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.)

The use of a down-flow fluidized bed (DFFB) reactor for the treatment of a sulfate-rich synthetic wastewater was investigated to obtain insight into the outcome of sulfate reduction in a biofilm attached to a plastic support under a down-flow regime. Fine low-density polyethylene particles were used as support for developing a biofilm within the reactor. The reactor treated a volatile fatty acids mixture of acetate or lactate, propionate, and butyrate at different chemical oxygen demand (COD) to sulfate ratios ranging from 1.67 to 0.67 (g/g). Organic loading rate changed from 2.5 to 5 g COD/L x day and sulfate loading rate increased from 1.5 to 7.3 g SO(4) (2-)/L x day. At the beginning of continuous operation, methanogenesis was the predominant process; however, after 187 days, sulfate reduction became the main ongoing biological process. After 369 days, a COD removal of 93% and a sulfate removal of 75% were reached. Total sulfide concentrations in the reactor ranged from 105, when the reactor was mainly methanogenic, to around 1,215 mg/L at the end of the experiment. The high sulfide concentrations did not affect the performance of the reactor. Results demonstrated that the configuration of the DFFB reactor was suitable for the anaerobic treatment of sulfate-rich wastewater., ((c) 2006 Wiley Periodicals, Inc.)