Nuclease Activity of the Junín Virus Nucleoprotein C-Terminal Domain.

The mammarenavirus Junín (JUNV) is the causative agent of Argentine hemorrhagic fever, a severe disease of public health concern. The most abundant viral protein is the nucleoprotein (NP), a multifunctional, two-domain protein with the primary role as structural component of the viral nucleocapsids, used as template for viral polymerase RNA synthesis activities. Here, we report that the C-terminal domain (CTD) of the attenuated Candid#1 strain of the JUNV NP can be purified as a stable soluble form with a secondary structure in line with known NP structures from other mammarenaviruses. We show that the JUNV NP CTD interacts with the viral matrix protein Z in vitro, and that the full-length NP and Z interact with each other in cellulo, suggesting that the NP CTD is responsible for this interaction. This domain comprises an arrangement of four acidic residues and a histidine residue conserved in the active site of exoribonucleases belonging to the DEDDh family. We show that the JUNV NP CTD displays metal-ion-dependent nuclease activity against DNA and single- and double-stranded RNA, and that this activity is impaired by the mutation of a catalytic residue within the DEDDh motif. These results further support this activity, not previously observed in the JUNV NP, which could impact the mechanism of the cellular immune response modulation of this important pathogen.

cis-Acting Element at the 5' Noncoding Region of Tacaribe Virus S RNA Modulates Genome Replication.

Tacaribe virus (TCRV) is the prototype of New World mammarenaviruses, a group that includes several members that cause hemorrhagic fevers in humans. The TCRV genome comprises two RNA segments, named S (small) and L (large). Both genomic segments contain noncoding regions (NCRs) at their 5' and 3' ends. While the 5'- and 3'-terminal 19-nucleotide sequences are known to be essential for promoter function, the role of their neighboring internal noncoding region (iNCR) sequences remains poorly understood. To analyze the relevance of the 5' and 3' iNCRs in TCRV S RNA synthesis, mutant S-like minigenomes and miniantigenomes were generated. Using a minireplicon assay, Northern blotting, and reverse transcription-quantitative PCR, we demonstrated that the genomic 5' iNCR is specifically engaged in minigenome replication yet is not directly involved in minigenome transcription, and we showed that the S genome 3' iNCR is barely engaged in this process. Analysis of partial deletions and point mutations, as well as total or partial substitution of the 5' iNCR sequence, led us to conclude that the integrity of the whole genomic 5' iNCR is essential and that a local predicted secondary structure or RNA-RNA interactions between the 5' and 3' iNCRs are not strictly required for viral S RNA synthesis. Furthermore, we employed a TCRV reverse genetic approach to ask whether manipulation of the S genomic 5' iNCR sequence may be suitable for viral attenuation. We found that mutagenesis of the 5' promoter-proximal subregion slightly impacted recombinant TCRV virulence in vivo. IMPORTANCE The Mammarenavirus genus of the Arenaviridae family includes several members that cause severe hemorrhagic fevers associated with high morbidity and mortality rates, for which no FDA-approved vaccines and limited therapeutic resources are available. We provide evidence demonstrating the specific involvement of the TCRV S 5' noncoding sequence adjacent to the viral promoter in replication. In addition, we examined the relevance of this region in the context of an in vivo infection. Our findings provide insight into the mechanism through which this 5' viral RNA noncoding region assists the L polymerase for efficient viral S RNA synthesis. Also, these findings expand our understanding of the effect of genetic manipulation of New World mammarenavirus sequences aimed at the rational design of attenuated recombinant virus vaccine platforms.

Cardiogenic shock code 2023. Expert document for a multidisciplinary organization that allows quality care.

Despite the efforts made to improve the care of cardiogenic shock (CS) patients, including the development of mechanical circulatory support (MCS), the prognosis of these patients continues to be poor. In this context, CS code initiatives arise, based on providing adequate, rapid, and quality care to these patients. In this multidisciplinary document we try to justify the need to implement the SC code, defining its structure/organization, activation criteria, patient flow according to care level, and quality indicators. Our specific purposes are: a) to present the peculiarities of this condition and the lessons of infarction code and previous experiences in CS; b) to detail the structure of the teams, their logistics and the bases for the management of these patients, the choice of the type of MCS, and the moment of its implantation, and c) to address challenges to SC code implementation, including the uniqueness of the pediatric SC code. There is an urgent need to develop protocolized, multidisciplinary, and centralized care in hospitals with a large volume and experience that will minimize inequity in access to the MCS and improve the survival of these patients. Only institutional and structural support from the different administrations will allow optimizing care for CS.

The Virus-Host Interplay in Junín Mammarenavirus Infection.

Junín virus (JUNV) belongs to the Arenaviridae family and is the causative agent of Argentine hemorrhagic fever (AHF), a severe human disease endemic to agricultural areas in Argentina. At this moment, there are no effective antiviral therapeutics to battle pathogenic arenaviruses. Cumulative reports from recent years have widely provided information on cellular factors playing key roles during JUNV infection. In this review, we summarize research on host molecular determinants that intervene in the different stages of the viral life cycle: viral entry, replication, assembly and budding. Alongside, we describe JUNV tight interplay with the innate immune system. We also review the development of different reverse genetics systems and their use as tools to study JUNV biology and its close teamwork with the host. Elucidating relevant interactions of the virus with the host cell machinery is highly necessary to better understand the mechanistic basis beyond virus multiplication, disease pathogenesis and viral subversion of the immune response. Altogether, this knowledge becomes essential for identifying potential targets for the rational design of novel antiviral treatments to combat JUNV as well as other pathogenic arenaviruses.

Desulfoluna spp. form a cosmopolitan group of anaerobic dehalogenating bacteria widely distributed in marine sponges.

Host-specific microbial communities thrive within sponge tissues and this association between sponge and associated microbiota may be driven by the organohalogen chemistry of the sponge animal. Several sponge species produce diverse organobromine secondary metabolites (e.g. brominated phenolics, indoles, and pyrroles) that may function as a chemical defense against microbial fouling, infection or predation. In this study, anaerobic cultures prepared from marine sponges were amended with 2,6-dibromophenol as the electron acceptor and short chain organic acids as electron donors. We observed reductive dehalogenation from diverse sponge species collected at disparate temperate and tropical waters suggesting that biogenic organohalides appear to enrich for populations of dehalogenating microorganisms in the sponge animal. Further enrichment by successive transfers with 2,6-dibromophenol as the sole electron acceptor demonstrated the presence of dehalogenating bacteria in over 20 sponge species collected from temperate and tropical ecoregions in the Atlantic and Pacific Oceans and the Mediterranean Sea. The enriched dehalogenating strains were closely related to Desulfoluna spongiiphila and Desulfoluna butyratoxydans, suggesting a cosmopolitan association between Desulfoluna spp. and various marine sponges. In vivo reductive dehalogenation in intact sponges was also demonstrated. Organobromide-rich sponges may thus provide a specialized habitat for organohalide-respiring microbes and D. spongiiphila and/or its close relatives are responsible for reductive dehalogenation in geographically widely distributed sponge species.

Immunomodulation of Oxidative Stress during Organ Donation Process: Preliminary Results.

The objective was to quantify oxidative stress resulting from ischemia during the donation process, using malondialdehyde (MDA) measurement, and its modulation by the administration of melatonin. We designed a triple-blind clinical trial with donors randomized to melatonin or placebo. We collected donors by donation after brain death (DBD) and controlled donation after circulatory death (DCD), the latter maintained by normothermic regional perfusion (NRP). Melatonin or placebo was administered prior to donation or following limitation of therapeutic effort (LTE). Demographic variables and medical history were collected. We also collected serial measurements of MDA, at 60 and 90 min after melatonin or placebo administration. A total of 53 donors were included (32 from DBD and 21 from DCD). In the DBD group, 17 donors received melatonin, and 15 placebo. Eight DCD donors were randomized to melatonin and 13 to placebo. Medical history and cause for LTE were similar between groups. Although MDA values did not differ in the DBD group, statistical differences were observed in DCD donors during the 0-60 min interval: -4.296 (-6.752; -2.336) in the melatonin group and -1.612 (-2.886; -0.7445) in controls. Given the antioxidant effect of melatonin, its use could reduce the production of oxidative stress in controlled DCD.

Deconstructing virus condensation.

Viruses have evolved precise mechanisms for using the cellular physiological pathways for their perpetuation. These virus-driven biochemical events must be separated in space and time from those of the host cell. In recent years, granular structures, known for over a century for rabies virus, were shown to host viral gene function and were named using terms such as viroplasms, replication sites, inclusion bodies, or viral factories (VFs). More recently, these VFs were shown to be liquid-like, sharing properties with membrane-less organelles driven by liquid-liquid phase separation (LLPS) in a process widely referred to as biomolecular condensation. Some of the best described examples of these structures come from negative stranded RNA viruses, where micrometer size VFs are formed toward the end of the infectious cycle. We here discuss some basic principles of LLPS in connection with several examples of VFs and propose a view, which integrates viral replication mechanisms with the biochemistry underlying liquid-like organelles. In this view, viral protein and RNA components gradually accumulate up to a critical point during infection where phase separation is triggered. This yields an increase in transcription that leads in turn to increased translation and a consequent growth of initially formed condensates. According to chemical principles behind phase separation, an increase in the concentration of components increases the size of the condensate. A positive feedback cycle would thus generate in which crucial components, in particular nucleoproteins and viral polymerases, reach their highest levels required for genome replication. Progress in understanding viral biomolecular condensation leads to exploration of novel therapeutics. Furthermore, it provides insights into the fundamentals of phase separation in the regulation of cellular gene function given that virus replication and transcription, in particular those requiring host polymerases, are governed by the same biochemical principles.

Development of a Reverse Genetic System to Generate Recombinant Chimeric Tacaribe Virus that Expresses Junín Virus Glycoproteins.

Mammarenaviruses are enveloped and segmented negative-stranded RNA viruses that comprise several pathogenic members associated with severe human hemorrhagic fevers. Tacaribe virus (TCRV) is the prototype for the New World group of mammarenaviruses and is not only naturally attenuated but also phylogenetically and antigenically related to all South American pathogenic mammarenaviruses, particularly the Junín virus (JUNV), which is the etiological agent of Argentinian hemorrhagic fever (AHF). Moreover, since TCRV protects guinea pigs and non-human primates from lethal challenges with pathogenic strains of JUNV, it has already been considered as a potential live-attenuated virus vaccine candidate against AHF. Here, we report the development of a reverse genetic system that relies on T7 polymerase-driven intracellular expression of the complementary copy (antigenome) of both viral S and L RNA segments. Using this approach, we successfully recovered recombinant TCRV (rTCRV) that displayed growth properties resembling those of authentic TCRV. We also generated a chimeric recombinant TCRV expressing the JUNV glycoproteins, which propagated similarly to wild-type rTCRV. Moreover, a controlled modification within the S RNA 5' non-coding terminal sequence diminished rTCRV propagation in a cell-type dependent manner, giving rise to new perspectives where the incorporation of additional attenuation markers could contribute to develop safe rTCRV-based vaccines against pathogenic mammarenaviruses.

Transplantation in Congenital Heart Disease: A Challenge.

BACKGROUND: Heart failure is the leading cause of death in grown-up congenital heart disease patients (GUCH). Although heart transplantation (OHT) remains the gold standard in end-stage heart failure, the ratio of GUCH patients undergoing this procedure remains low. OBJECTIVE: Describe the cohort of GUCH patients undergoing heart transplantation at a third-level hospital. METHODS: A retrospective review of GUCH patients undergoing OHT between 1997 and 2019 was conducted at a single tertiary university hospital. We included different preoperative (demographic and clinical data, cardiac catheterization data from the last routine hemodynamic monitoring) and postoperative variables (complications, survival). RESULTS: Fourteen patients were enrolled. The median age was 25.5 years (range, 20.7-32.2). Eight patients (57.1%) were male. The median preoperative left ventricular ejection fraction was 37% (range, 22.5%-55%). As for preoperative hemodynamic evaluation, the median for the mean arterial pulmonary pressure was 19 mm Hg (range, 12-22.5), for the capillary wedge pressure was 16 mm Hg (range, 13.5-19.5), and for pulmonary vascular resistance was 1.83 Wood units (range, 1-4). After OHT, 6 patients (42.9%) suffered an infection, the most common of which was respiratory (3 out of 6). Four patients (28.6%) needed renal replacement therapy, and 4 patients (28.6%) presented liver failure. Four patients (28.6%) developed graft failure, thus requiring mechanical support with extracorporeal membrane oxygenation during a median of 6 days (range, 1-17.5). Survival rate of patients under extracorporeal membrane oxygenation was 50%, and overall survival rate was 78.6%. CONCLUSION: OHT represents a good option for GUCH patients, with good overall survival rates.

Right Ventricular Assist Devices After Heart Transplantation.

BACKGROUND: Severe right ventricular failure (RVF) has a significant incidence among cardiac transplant patients. It is a serious complication and an independent risk factor for postoperative mortality. In this setting, ventricular assist devices (VADs) must be considered if conservative medical management fails. This study sought to examine our series of patients with early RVF after heart transplantation requiring VAD support. METHOD: We analyzed consecutive, adult heart transplant recipients at a third level intensive care unit who underwent transplantation from January 2011 to March 2019 requiring post-transplant mechanical circulatory support for RVF. Demographic characteristics, clinical data, complications, and survival rates were collected. RESULTS: Ten patients were included. Median age was 50 years (range, 31.7-57). Eight patients (80%) were male. The most frequent indication for heart transplantation was ischemic heart disease (4 patients) followed by dilated cardiomyopathy and congenital heart disease (2 patients). Preoperative pulmonary hypertension was present in 6 patients. Three patients required a VAD before transplant. Whole survival rate was 60%. After heart transplantation, 7 patients required renal replacement therapy, 2 patients suffered a hemorrhagic stroke, and 5 patients needed a tracheostomy for long-term ventilation. CONCLUSION: Patients who develop RVF after transplantation have an increased incidence of complications and high mortality after surgery. VADs could be implanted immediately after heart transplantation in high-risk patients.

Cuerpos extraños radiopacos con doble contorno en la vía digestiva: ¿son siempre pilas de botón? / Are strange radiopaque bodies with double contours in the digestive tract always button cell batteries?

Resumen La ingesta accidental de cuerpos extraños constituye una emergencia en los servicios de atención pediátrica y el grupo más frecuentemente afectado se encuentra en los pacientes entre los 6 meses y los 3 años. Asimismo, la ingesta de pilas de botón es un factor de riesgo importante para el desarrollo de complicaciones tempranas severas como la perforación esofágica y mediastinitis, y a largo plazo, la aparición de estenosis. Por este motivo, su identificación temprana y la extracción constituyen las estrategias más importantes de manejo. Se ha descrito como característico el hallazgo del doble contorno en la radiografía frontal cérvico-toracoabdominal en estos pacientes. Sin embargo, se ha reportado el mismo signo radiológico en cuerpos extraños diferentes. En el presente artículo se presentan dos casos con estas características.

Abstract Accidental ingestion of foreign bodies constitutes an emergency for pediatric care services especially since the group most frequently affected consists of children between 6 months and 3 years of age. Ingestion of button cell batteries has high risks for severe early complications such as esophageal perforations and mediastinitis, as well as the long term risk of stenosis. Early identification and extraction are the most important management strategies. A double contour on a frontal cervical, thoracic, or abdominal x-ray is characteristic, but this same radiological sign has been reported for other foreign bodies. We present two cases with these characteristics.

Estructura poblacional y hábitat de un árbol tropical con frutos comestibles, Annona purpurea (Annonaceae), en el occidente de México

Introducción: Annona purpurea es un árbol Mesoamericano, distribuido por la vertiente pacífica y atlántica de México hasta Sudamérica. Diferentes partes de la planta son de utilidad y los frutos son comestibles. Objetivo: Describir la estructura poblacional, el hábitat y los factores ambientales que influyen en la distribución y abundancia de A. purpurea en el occidente de México. Métodos: De abril a noviembre 2015, se establecieron 24 unidades de muestreo de 500 m2 cada una, con presencia de A. purpurea. En cada sitio se midieron e identificaron todas las especies leñosas con diámetro a la altura de pecho (dap) ≥ 2.5 cm y se registró información ambiental, geográfica y climática. Se obtuvo información sobre la repoblación de la especie. Se estimó la estructura de A. purpurea y se examinaron sus relaciones con las variables ambientales. El índice de asociación de Whittaker se determinó utilizando la matriz de índice de valor de importancia (IVI). Con la matriz de variables ambientales y la de IVI, se realizó un Análisis de Correspondencia Canónica para determinar la influencia de las variables ambientales sobre la especie y visualizar la distribución de las especies en el espacio multidimensional. Resultados: A. purpurea presentó 1 108 tallos en 1.2 ha, con el 85 % de ellos concentrados en las tres primeras categorías diamétricas. Su densidad presentó una relación positiva con la presencia de tocones, mientras que el área basal y el IVI se relacionaron de manera similar con la incidencia de incendios. Hubo poca o nula regeneración de A. purpurea debajo de su dosel. Los mayores IVI en la comunidad se registraron para A. purpurea, Tabebuia rosea, Quercus magnoliifolia y Enterolobium cyclocarpum y la prueba de perfiles de semejanza separó a A. purpurea y Guazuma ulmifolia como un grupo diferente. Las variables ambientales con mayor influencia en la distribución y abundancia de A. purpurea fueron la precipitación anual, incidencia de incendios, elevación, temperatura media anual, pedregosidad y pastoreo. Conclusión: A. purpurea presenta los mayores atributos estructurales en la comunidad, sus poblaciones se ven favorecidas en sitios con mayor precipitación y temperatura, con poca pedregosidad, donde hay incidencia de perturbaciones por fuego y ganado que generan claros grandes y su mayor asociación la presenta con G. ulmifolia.

Introduction: Annona purpurea is a Mesoamerican tree, distributed from the Pacific and Atlantic slopes of Mexico to South America. Different parts of the plant are of utility and the fruits are edible. Objective: To describe the population structure, habitat and environmental factors that influence the distribution and abundance of A. purpurea in Western Mexico. Methods: From April to November 2015, 24 sampling units were established, each of which were 500 m2 in area and had a presence of A. purpurea. At each site, all woody species with a diameter at breast height (dap) ≥ 2.5 cm were measured and identified, and environmental, geographic and climatic information recorded. Information regarding the regeneration of the species was obtained. The structure of A. purpurea was estimated and its relationships with environmental variables examined. The Whittaker association index was determined using the importance value index matrix (IVI). With the matrix of environmental variables and that of IVI, a Canonical Correspondence Analysis was performed to determine the influence of environmental variables on the species and to visualize the distribution of the species in multidimensional space. Results: A. purpurea presented 1 108 stems in 1.2 ha, with 85 % of these concentrated in the first three diametric categories. Its density presented a positive relationship with the presence of stumps, while the basal area and IVI were similarly related to the incidence of fire. There was little or no regeneration of A. purpurea under its canopy. The highest IVI in the community were found for A. purpurea, Tabebuia rosea, Quercus magnoliifolia and Enterolobium cyclocarpum, and the similarity profiles test separated A. purpurea and Guazuma ulmifolia as a distinct group. The environmental variables with the greatest influence on the distribution and abundance of A. purpurea were annual precipitation, fire incidence, elevation, mean annual temperature, stoniness and livestock. Conclusion: A. purpurea presents the greatest structural attributes in the community, its populations are favored in places with greater precipitation and temperature, with little stoniness and with incidence of disturbances by fire and livestock that generate large gaps and its greatest association is with G. ulmifolia.

Normothermic Regional Perfusion and Donation After Circulatory Death (Controlled and Uncontrolled): Metabolic Differences and Kidney Transplantation Evolution.

OBJECTIVE: To analyze metabolic differences during normothermic regional perfusion (NRP) between the dissimilar types of donation after circulatory death, uncontrolled (uDCD) and controlled (cDCD), and the evolution of the transplanted kidneys. METHODS: Observational, prospective, cohort study. We included patients from uDCD and cDCD maintained with NRP in 2017. Six consecutive blood gases were collected with determination of pH and lactic acid. Creatinine levels were monitored at 24 hours, 3 months, and 6 months after transplant and the need for renal replacement therapy was evaluated. Descriptive statistical analysis was performed, presenting the qualitative variables as frequencies and percentages, and quantitative as mean ± SD or median (interquartile range [IQR]). We used χ2 testing for bivariate analysis of qualitative variables. RESULTS: We collected 18 donors. Fifteen out of 18 (83.3%) were men with a median of 51 years (IQR, 46-60). Eleven out of 18 (61.1%) were cDCD and 7 out of 18 (38.9%) were uDCD. The blood gas results are illustrated in Table 1. A total of 28 renal transplants were obtained with a median age of 47 years (IQR, 45-57); 83% were male. Ten out of 28 (35.7%) came from uDCD and 18 out of 28 (64.7%) from cDCD. Table 2 shows the monitoring of the creatinine values of the recipients after the transplantation. CONCLUSIONS: There are more metabolic disorders in our series in uDCD organ donation compared with cDCD. The recovery of the renal function of organs from uDCD is slower than that of cDCD, however; the tendency is toward normality.

Plasma fresco congelado precoz en el shock hemorrágico, ¿estamos seguros? / Early fresh frozen plasma for hemorrhagic shock: Are we sure?

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Virus⁻Host Interactions Involved in Lassa Virus Entry and Genome Replication.

Lassa virus (LASV) is the causative agent of Lassa fever, a human hemorrhagic disease associated with high mortality and morbidity rates, particularly prevalent in West Africa. Over the past few years, a significant amount of novel information has been provided on cellular factors that are determinant elements playing a role in arenavirus multiplication. In this review, we focus on host proteins that intersect with the initial steps of the LASV replication cycle: virus entry and genome replication. A better understanding of relevant virus⁻host interactions essential for sustaining these critical steps may help to identify possible targets for the rational design of novel therapeutic approaches against LASV and other arenaviruses that cause severe human disease.

DDX3 suppresses type I interferons and favors viral replication during Arenavirus infection.

Several arenaviruses cause hemorrhagic fever (HF) diseases that are associated with high morbidity and mortality in humans. Accordingly, HF arenaviruses have been listed as top-priority emerging diseases for which countermeasures are urgently needed. Because arenavirus nucleoprotein (NP) plays critical roles in both virus multiplication and immune-evasion, we used an unbiased proteomic approach to identify NP-interacting proteins in human cells. DDX3, a DEAD-box ATP-dependent-RNA-helicase, interacted with NP in both NP-transfected and virus-infected cells. Importantly, DDX3 deficiency compromised the propagation of both Old and New World arenaviruses, including the HF arenaviruses Lassa and Junin viruses. The DDX3 role in promoting arenavirus multiplication associated with both a previously un-recognized DDX3 inhibitory role in type I interferon production in arenavirus infected cells and a positive DDX3 effect on arenavirus RNA synthesis that was dependent on its ATPase and Helicase activities. Our results uncover novel mechanisms used by arenaviruses to exploit the host machinery and subvert immunity, singling out DDX3 as a potential host target for developing new therapies against highly pathogenic arenaviruses.

Role of the ERK1/2 Signaling Pathway in the Replication of Junín and Tacaribe Viruses.

We have previously shown that the infection of cell cultures with the arenaviruses Junín (JUNV), Tacaribe (TCRV), and Pichindé promotes the phosphorylation of mitogen-activated protein kinases (MAPKs) extracellular signal-regulated kinases 1 and 2 (ERK1/2) and that this activation is required for the achievement of a productive infection. Here we examined the contribution of ERK1/2 in early steps of JUNV and TCRV multiplication. JUNV adsorption, internalization, and uncoating were not affected by treatment of cultured cells with U0126, an inhibitor of the ERK1/2 signaling pathway. In contrast, U0126 caused a marked reduction in viral protein expression and RNA synthesis, while JUNV RNA synthesis was significantly augmented in the presence of an activator of the ERK1/2 pathway. Moreover, U0126 impaired the expression of a reporter gene in a TCRV-based replicon system, confirming the ability of the compound to hinder arenavirus macromolecular synthesis. By using a cell-based assay, we determined that the inhibitor did not affect the translation of a synthetic TCRV-like mRNA. No changes in the phosphorylation pattern of the translation factor eIF2α were found in U0126-treated cells. Our results indicate that U0126 impairs viral RNA synthesis, thereby leading to a subsequent reduction in viral protein expression. Thus, we conclude that ERK1/2 signaling activation is required for an efficient arenavirus RNA synthesis.

Gender-Associated Impact of Early Leucine Supplementation on Adult Predisposition to Obesity in Rats.

Early nutrition plays an important role in development and may constitute a relevant contributor to the onset of obesity in adulthood. The aim of this study was to evaluate the long-term impact of maternal leucine (Leu) supplementation during lactation on progeny in rats. A chow diet, supplemented with 2% Leu, was supplied during lactation (21 days) and, from weaning onwards, was replaced by a standard chow diet. Then, at adulthood (6 months of age), this was replaced with hypercaloric diets (either with high-fat (HF) or high-carbohydrate (HC) content), for two months, to induce obesity. Female offspring from Leu-supplemented dams showed higher increases in body weight and in body fat (62%) than their respective controls; whereas males were somehow protected (15% less fat than the corresponding controls). This profile in Leu-females was associated with altered neuronal architecture at the paraventricular nucleus (PVN), involving neuropeptide Y (NPY) fibers and impaired expression of neuropeptides and factors of the mTOR signaling pathway in the hypothalamus. Interestingly, leptin and adiponectin expression in adipose tissue at weaning and at the time before the onset of obesity could be defined as early biomarkers of metabolic disturbance, predisposing towards adult obesity under the appropriate environment.

Novel reductive dehalogenases from the marine sponge associated bacterium Desulfoluna spongiiphila.

Desulfoluna spongiiphila strain AA1 is an organohalide respiring bacterium, isolated from the marine sponge Aplysina aerophoba, that can use brominated and iodinated phenols, in addition to sulfate and thiosulfate as terminal electron acceptors. The genome of Desulfoluna spongiiphila strain AA1 is approximately 6.5 Mb. Three putative reductive dehalogenase (rdhA) genes involved in respiratory metabolism of organohalides were identified within the sequence. Conserved motifs found in respiratory reductive dehalogenases (a twin arginine translocation signal sequence and two iron-sulfur clusters) were present in all three putative AA1 rdhA genes. Transcription of one of the three rdhA genes was significantly upregulated during respiration of 2,6-dibromophenol and sponge extracts. Strain AA1 appears to have the ability to synthesize cobalamin, the key cofactor of most characterized reductive dehalogenase enzymes. The genome contains genes involved in cobalamin synthesis and uptake and can grow without cobalamin supplementation. Identification of this target gene associated with debromination lays the foundation for understanding how dehalogenating bacteria control the fate of organohalide compounds in sponges and their role in a symbiotic organobromine cycle. In the sponge environment, D. spongiiphila strain AA1 may thus take advantage of both brominated compounds and sulfate as electron acceptors for respiration.