13 research outputs found
Human Type I Interferon Antiviral Effects in Respiratory and Reemerging Viral Infections
Type I interferons (IFN-I) are a group of related proteins that help regulate the activity of the immune system and play a key role in host defense against viral infections. Upon infection, the IFN-I are rapidly secreted and induce a wide range of effects that not only act upon innate immune cells but also modulate the adaptive immune system. While IFN-I and many IFN stimulated genes are well-known for their protective antiviral role, recent studies have associated them with potential pathogenic functions. In this review, we summarize the current knowledge regarding the complex effects of human IFN-I responses in respiratory as well as reemerging flavivirus infections of public health significance and the molecular mechanisms by which viral proteins antagonize the establishment of an antiviral host defense. Antiviral effects and immune modulation of IFN-stimulated genes is discussed in resisting and controlling pathogens. Understanding the mechanisms of these processes will be crucial in determining how viral replication can be effectively controlled and in developing safe and effective vaccines and novel therapeutic strategies
Chemical structure and antiviral activity of carrageenans from Meristiella gelidium against herpes simplex and dengue virus
Chemical and spectroscopic methods showed that the major KCl-precipitated galactans from Meristiella gelidium (Solieriaceae) are iota/kappa/nu-hybrid carrageenans with the former one in higher proportion. These carrageenans showed, by HPSEC-MALLS analysis, unimodal symmetrical peaks with MW of 425.6–956.7 kDa. The effectiveness of the crude extracts from M. gelidium against HSV-2 was higher than the corresponding extract from G. griffithsiae, previously determined. However, when considering the homogeneous carrageenans, the fractions obtained from both seaweeds showed the same level of activity. The extracts and carrageenan derived from M. gelidium were more effective inhibitors of DENV-2 if compared with G. griffithsiae samples and reference polysaccharides. The most active fraction obtained from M. gelidium showed a selectivity index against HSV-2 of 25,000, a value high enough to consider this carrageenan as a promising agent to be evaluated for the treatment of genital HSV-2 infections.Fil: De S.F. Tischer, Paula Cristina. Universidade Federal do Paraná; BrasilFil: Talarico, Laura Beatriz. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de QuĂmica BiolĂłgica. Laboratorio de VirologĂa; ArgentinaFil: Noseda, Miguel D.. Universidade Federal do Paraná; BrasilFil: Pita B. GuimarĂŁes, Silvia Maria. Instituto de Botânica; BrasilFil: Damonte, Elsa Beatriz. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de QuĂmica BiolĂłgica. Laboratorio de VirologĂa; ArgentinaFil: Duarte, Maria EugĂŞnia R.. Universidade Federal do Paraná; Brasi
Interleukin-13 associates with life-threatening rhinovirus infections in infants and young children
Objective: Delineate risk factors associated with severe hypoxemia (O2 sat ≤87%) in infants and children younger than 2 years hospitalized with single pathogen HRV infection. Study Design: Prospective study in a yearly catchment population of 56 560 children 10 pg/mL) predisposed to life-threatening disease. Conclusions: Targeted interventions against IL-13 should be evaluated to decrease severity of HRV illness in infancy and early childhood.Fil: Caballero, Mauricio Tomás. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. FundaciĂłn para la InvestigaciĂłn en InfectologĂa Infantil; ArgentinaFil: Hijano, Diego RaĂşl. FundaciĂłn para la InvestigaciĂłn en InfectologĂa Infantil; Argentina. St. Jude Children's Research Hospital; Estados UnidosFil: Acosta, Patricio Leandro. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. FundaciĂłn para la InvestigaciĂłn en InfectologĂa Infantil; ArgentinaFil: Mateu, Cecilia Gabriela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. FundaciĂłn para la InvestigaciĂłn en InfectologĂa Infantil; ArgentinaFil: Marcone, DĂ©bora Natalia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Centro de EducaciĂłn MĂ©dica e Investigaciones ClĂnicas “Norberto Quirno”; ArgentinaFil: Linder, Jodell E.. Vanderbilt University; Estados UnidosFil: Talarico, Laura Beatriz. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. FundaciĂłn para la InvestigaciĂłn en InfectologĂa Infantil; ArgentinaFil: Elder, John M.. Vanderbilt University; Estados UnidosFil: EchavarrĂa, Marcela Silvia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Centro de EducaciĂłn MĂ©dica e Investigaciones ClĂnicas “Norberto Quirno”; ArgentinaFil: Miller, Eva Kathryn. Vanderbilt University; Estados UnidosFil: Polack, Fernando Pedro. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. FundaciĂłn para la InvestigaciĂłn en InfectologĂa Infantil; Argentin
(Table 2) Salinity, pH, alkalinity and major ion concentrations in ANDRILL core AND-2A pore water
The compositional record of the AND-2A drillcore is examined using petrological, sedimentological, volcanological and geochemical analysis of clasts, sediments and pore waters. Preliminary investigations of basement clasts (granitoids and metasediments) indicate both local and distal sources corresponding to variable ice-volume and ice-flow directions. Low abundance of sedimentary clasts (e.g., arkose, litharenite) suggests reduced contributions from sedimentary covers while intraclasts (e.g., diamictite, conglomerate) attest to intrabasinal reworking. Volcanic material includes pyroclasts (e.g., pumice, scoria), sediments and lava. Primary and reworked tephra layers occur within the Early Miocene interval (1093 to 640 metres below sea floor mbsf). The compositions of volcanic clasts reveal a diversity of alkaline types derived from the McMurdo Volcanic Group. Finer-grained sediments (e.g., sandstone, siltstone) show increases in biogenic silica and volcanic glass from 230 to 780 mbsf and higher proportions of terrigenous material c. 350 to 750 mbsf and below 970 mbsf. Basement clast assemblages suggest a dominant provenance from the Skelton Glacier - Darwin Glacier area and from the Ferrar Glacier - Koettlitz Glacier area. Provenance of sand grains is consistent with clast sources. Thirteen Geochemical Units are established based on compositional trends derived from continuous XRF scanning. High values of Fe and Ti indicate terrigenous and volcanic sources, whereas high Ca values signify either biogenic or diagenic sources. Highly alkaline and saline pore waters were produced by chemical exchange with glass at moderately elevated temperatures
A large West Antarctic ice sheet explains early Neogene sea-level amplitude
Early to Middle Miocene sea-level oscillations of approximately 40–60 m estimated from far-field records1–3 are interpreted to reflect the loss of virtually all East Antarctic ice during peak warmth2. This contrasts with ice-sheet model experiments suggesting most terrestrial ice in East Antarctica was retained even during the warmest intervals of the Middle Miocene4,5. Data and model outputs can be reconciled if a large West Antarctic Ice Sheet (WAIS) existed and expanded across most of the outer continental shelf during the Early Miocene, accounting for maximum ice-sheet volumes. Here we provide the earliest geological evidence proving large WAIS expansions occurred during the Early Miocene (~17.72–17.40 Ma). Geochemical and petrographic data show glacimarine sediments recovered at International Ocean Discovery Program (IODP) Site U1521 in the central Ross Sea derive from West Antarctica, requiring the presence of a WAIS covering most of the Ross Sea continental shelf. Seismic, lithological and palynological data reveal the intermittent proximity of grounded ice to Site U1521. The erosion rate calculated from this sediment package greatly exceeds the long-term mean, implying rapid erosion of West Antarctica. This interval therefore captures a key step in the genesis of a marine-based WAIS and a tipping point in Antarctic ice-sheet evolution
Exome sequencing of 20,979 individuals with epilepsy reveals shared and distinct ultra-rare genetic risk across disorder subtypes
Identifying genetic risk factors for highly heterogeneous disorders such as epilepsy remains challenging. Here we present, to our knowledge, the largest whole-exome sequencing study of epilepsy to date, with more than 54,000 human exomes, comprising 20,979 deeply phenotyped patients from multiple genetic ancestry groups with diverse epilepsy subtypes and 33,444 controls, to investigate rare variants that confer disease risk. These analyses implicate seven individual genes, three gene sets and four copy number variants at exome-wide significance. Genes encoding ion channels show strong association with multiple epilepsy subtypes, including epileptic encephalopathies and generalized and focal epilepsies, whereas most other gene discoveries are subtype specific, highlighting distinct genetic contributions to different epilepsies. Combining results from rare single-nucleotide/short insertion and deletion variants, copy number variants and common variants, we offer an expanded view of the genetic architecture of epilepsy, with growing evidence of convergence among different genetic risk loci on the same genes. Top candidate genes are enriched for roles in synaptic transmission and neuronal excitability, particularly postnatally and in the neocortex. We also identify shared rare variant risk between epilepsy and other neurodevelopmental disorders. Our data can be accessed via an interactive browser, hopefully facilitating diagnostic efforts and accelerating the development of follow-up studies