Successful kinetic impact into an asteroid for planetary defence.

Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation1,2. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid1-3. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation1. NASA's Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission's target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft4. Although past missions have utilized impactors to investigate the properties of small bodies5,6, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft's autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos7 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.

[Controversies on corticosteroid therapy in hantavirus cardiopulmonary syndrome]. / Controversias sobre el uso de corticoides en el síndrome cardiopulmonar por hantavirus.

Hantavirus cardiopulmonary syndrome is an emerging zoonosis in Argentina, which has low incidence but high death rates. No specific pharmacological therapy is available and symptomatic therapy is the only current alternative. This article presents the pathogenesis of hantavirus cardiopulmonary syndrome through a review of clinical experiences in neighbor South American countries, mainly Chile, and the experience acquired at the Infectious Diseases Hospital Francisco Javier Muñiz, Buenos Aires, Argentina. The role of early corticosteroid therapy is discussed taking into account that there is insufficient evidence favoring its use in the hantavirus cardiopulmonary syndrome.

El síndrome cardiopulmonar por hantavirus es una zoonosis emergente en la Argentina, que presenta baja incidencia, pero elevada mortalidad. No existe tratamiento farmacológico especifico y la única alternativa actual es la terapia de apoyo. En este artículo se expone la patogenia del síndrome cardiopulmonar por hantavirus a través de la revisión de las experiencias clínicas de otros países de Sudamérica, en particular Chile, y la adquirida en el Hospital de Infecciosas Francisco Javier Muñiz de Buenos Aires, Argentina. Se discute sobre la administración temprana de corticoides en este síndrome, teniendo en cuenta que la evidencia a favor de su uso es insuficiente.

Controversias sobre el uso de corticoides en el síndrome cardiopulmonar por hantavirus / Controversies on corticosteroid therapy in hantavirus cardiopulmonary syndrome

Resumen El síndrome cardiopulmonar por hantavirus es una zoonosis emergente en la Argentina, que presenta baja incidencia, pero elevada mortalidad. No existe tratamiento farmacológico especifico y la única alternativa actual es la terapia de apoyo. En este artículo se expone la patogenia del síndrome cardiopulmonar por hantavirus a través de la revisión de las experiencias clínicas de otros países de Sudamérica, en particular Chile, y la adquirida en el Hospital de Infecciosas Francisco Javier Muñiz de Buenos Aires, Argentina. Se discute sobre la administración temprana de corticoides en este síndrome, teniendo en cuenta que la evidencia a favor de su uso es insuficiente.

Abstract Hantavirus cardiopulmonary syndrome is an emerging zoonosis in Argentina, which has low incidence but high death rates. No specific pharmacological therapy is available and symptomatic therapy is the only current alterna tive. This article presents the pathogenesis of hantavirus cardiopulmonary syndrome through a review of clinical experiences in neighbor South American countries, mainly Chile, and the experience acquired at the Infectious Diseases Hospital Francisco Javier Muñiz, Buenos Aires, Argentina. The role of early corticosteroid therapy is discussed taking into account that there is insufficient evidence favoring its use in the hantavirus cardiopulmonary syndrome.

TLR4 genotype and environmental LPS mediate RSV bronchiolitis through Th2 polarization.

While 30%-70% of RSV-infected infants develop bronchiolitis, 2% require hospitalization. It is not clear why disease severity differs among healthy, full-term infants; however, virus titers, inflammation, and Th2 bias are proposed explanations. While TLR4 is associated with these disease phenotypes, the role of this receptor in respiratory syncytial virus (RSV) pathogenesis is controversial. Here, we evaluated the interaction between TLR4 and environmental factors in RSV disease and defined the immune mediators associated with severe illness. Two independent populations of infants with RSV bronchiolitis revealed that the severity of RSV infection is determined by the TLR4 genotype of the individual and by environmental exposure to LPS. RSV-infected infants with severe disease exhibited a high GATA3/T-bet ratio, which manifested as a high IL-4/IFN-γ ratio in respiratory secretions. The IL-4/IFN-γ ratio present in infants with severe RSV is indicative of Th2 polarization. Murine models of RSV infection confirmed that LPS exposure, Tlr4 genotype, and Th2 polarization influence disease phenotypes. Together, the results of this study identify environmental and genetic factors that influence RSV pathogenesis and reveal that a high IL-4/IFN-γ ratio is associated with severe disease. Moreover, these molecules should be explored as potential targets for therapeutic intervention.

A multibiomarker approach in the clam Ruditapes decussatus to assess the impact of pollution in the Ria Formosa lagoon, South Coast of Portugal.

The Ria Formosa lagoon is an ecosystem whose water quality reflects the anthropogenic influence upon the surrounding areas. In this lagoon, the clam Ruditapes decussatus has a great economical importance and has been widely used as a biomonitor. A multibiomarker approach (δ-aminolevulinic acid dehydratase, metallothionein, lipid peroxidation, acetylcholinesterase, alkali-labile phosphates, DNA damage) was applied to assess the environmental quality of this ecosystem and the accumulation of contaminants and their potential adverse effects on clams. Clams were sampled in different shellfish beds in the period between July 2007 and December 2008 and abiotic parameters (temperature, salinity, pH and dissolved oxygen of seawater and organic matter in the sediment), condition index, metals (Cd, Cu, Zn, Ni, Pb), TBTs and PAHs concentrations were measured in clam tissues. Data was integrated using Principal Component Analyses and biomarker indices: IBR (Integrated Biomarker Response) and HSI (Health Status Index). This multibiomarker approach enabled discrimination of a time and space trend between sites with different degrees of anthropogenic contamination, identifying one of them (site 2) as the most stressful and summer months as the most critical period for clams due to an increase of environmental stress (anthropogenic pressure along with extreme environmental conditions, e.g. temperature, dissolved oxygen, organic matter in the sediments, etc). The selected biomarkers provided an integrated response to assess the environmental quality of the system, proving to be a useful approach when complex mixtures of contaminants occur.

Breastfeeding prevents severe disease in full term female infants with acute respiratory infection.

BACKGROUND: Breastfeeding is a well-known protective factor against severe respiratory tract infections. Recently, a gender specific role for human milk has been described in very low birth weight infants and neonates: breast milk protected girls but not boys. OBJECTIVE: To determine whether the protective effect of breastfeeding on the severity of acute respiratory infections in full term infants is different for girls and boys. METHODS: A prospective cross-sectional study of infants seeking medical care for acute respiratory infection. The protective role of breastfeeding against viral pneumonia and hospitalization were assessed by univariate and multivariate analyses. Analyses were adjusted for important confounders. RESULTS: A total of 323 patients were enrolled in this study. Breastfeeding protected girls against pneumonia and hospitalization, but did not protect boys. Nonbreastfeeding females were particularly susceptible to severe acute respiratory infections. CONCLUSIONS: Breastfeeding had a protective effect against severe disease in infant girls experiencing their first symptomatic respiratory infection. Nonbreastfeeding females are at significant risk for severe acute lung disease and should be targeted intensively by breastfeeding campaigns.

Cytokine profiles in the respiratory tract during primary infection with human metapneumovirus, respiratory syncytial virus, or influenza virus in infants.

OBJECTIVES: We characterized the T helper cytokine profiles in the respiratory tract of infants infected with influenza virus, human metapneumovirus, and respiratory syncytial virus to examine whether these agents elicit similar cytokine responses and whether T helper type 2 polarization is associated with wheezing and severe disease. METHODS: A prospective study of infants who were seeking medical help for acute upper and/or lower respiratory tract infection symptoms for the first time and were found to be infected with influenza, human metapneumovirus, or respiratory syncytial virus was performed. Respiratory viruses were detected in nasal secretions with reverse transcriptase-polymerase chain reaction assays. The study was performed in emergency departments and outpatient clinics in Buenos Aires, Argentina. T cell cytokine responses were determined in nasal secretions with immunoassays and reverse transcriptase-polymerase chain reaction assays. RESULTS: Influenza elicited higher levels of interferon-gamma, interleukin-4, and interleukin-2 than did the other agents. Human metapneumovirus had the lowest interferon-gamma/interleukin-4 ratio (T helper type 2 bias). However, no association was found between T helper type 2 bias and overall wheezing or hospitalization rates. CONCLUSIONS: These findings show that viral respiratory infections in infants elicit different cytokine responses and that the pathogeneses of these agents should be studied individually.

Differential production of inflammatory cytokines in primary infection with human metapneumovirus and with other common respiratory viruses of infancy.

Viral respiratory infections are the most frequent cause of hospital admission for infants and young children during winter. However, the mechanisms of illness that are associated with viral lower-respiratory-tract infection (LRI) are unclear. A widely accepted hypothesis attributes the pathogenesis of viral LRI in infants to the induction of innate inflammatory responses. This theory is supported by studies showing that Toll-like receptor 4 is activated by respiratory syncytial virus (RSV), leading to production of inflammatory cytokines. We prospectively examined previously naive infants in Buenos Aires, Argentina, who had either upper- or lower-respiratory-tract symptoms. Infection with human metapneumovirus (hMPV) was second only to RSV in frequency. Both viruses were associated with rhinorrhea, cough, and wheezing; however, hMPV elicited significantly lower levels of respiratory inflammatory cytokines than did RSV. Symptoms in infants infected with influenza virus were different from those in infants infected with RSV, but cytokine responses were similar. These findings suggest that hMPV and RSV either cause disease via different mechanisms or share a common mechanism that is distinct from innate immune activation.

Freeze dried irradiated amnion in burns

Thirty nine partial thickness burns ranging from 0.5% to 6% total surface body area in thirty two patients were treated with the application of freeze dried irradiated amnion during an eighteen month period from July 1989 to December 1990. It was observed that in all these burns wounds, there was relief of pain upon application and control of oozing from the wound. In addition, healing of the wounds was unremarkable with no occurrence of infection. Scab separation was completed at an average of 9.9 days. Freeze dried, irradiated amnion was found to be effective as a biologic dressing in the treatment of burns for prolonged periods using this unique storage process.(Author)